Aga temp problem?
The Natural Philosopher
Oil fired new aga, after 18 months suddenly - or possibly gradually -
running cooler and cooler according to thermometer.
The electrical stat seems to be working - I have stuck it manually on
'overdrive' but it still is running at idle basically?
Any ideas before I call in the engineer?
IMM
"The Natural Philosopher" <a@b.c> wrote in message
news:3F28FAE4.3090405@b.c...
Sadly, the only solution is to throw it out. get yourself something decent
and efficient.
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@my_last_name.org.uk Richard Caley
tnp> Any ideas before I call in the engineer?
Do Dyson make one?
--
Mail me as MYFIR...@MYLASTNAME.org.uk _O_
|<
Grunff
> Sadly, the only solution is to throw it out. get yourself something decent
> and efficient.
<OMG> - I think this is the second time I've agreed with you in
as many weeks. I'm really starting to worry.
I know Agas have a massive following, and that people love them
to death and swoon over them, but I find them to be horrible,
loathsome things.
--
Grunff
CJ
Yea this one isn't even self cleaning! ;-)
Anyone know the efficiency of an oil fired Aga?
--
remove ".nospam" from my reply address
Richard
"The Natural Philosopher" <a@b.c> wrote in message
news:3F28FAE4.3090405@b.c...
18 Months, Have you had the burner serviced in that time? An Oil fired Aga
with light usage can probably get away with about a nine month service
interval. I always do mine at 6 month intervals and over many, many years
the only problem I have ever had was failure of the thermostat. Incidentally
the thermostat fails high so that is not your problem.
This is a DIY NG. so why are you considering calling an engineer out to your
Aga? Once you know how to diagnose and service an Aga the exercise is
simplicity itself.
Richard.
IMM
"Grunff" <gru...@ixxa.com> wrote in message
news:bgb0t8$metgf$1...@ID-152899.news.uni-berlin.de...
> IMM wrote:
>
> > Sadly, the only solution is to throw it out. get yourself something
decent
> > and efficient.
>
> <OMG> - I think this is the second time I've agreed with you in
> as many weeks. I'm really starting to worry.
Keep walking, further down the road to Damascus you will be fully
enlightened.
> I know Agas have a massive following, and that people love them
> to death and swoon over them, but I find them to be horrible,
> loathsome things.
I couldn't agree more. The sort of people who buy them are the sort who
voted for Britain's best house the other night. That house? Never in a
million years. In my mind I never even considered it wondering how it was
even in the final. then it won. Or did the gay community all vote for
those two old Queens.
Andy Hall
wrote:
>No doubt IMM will delight in this one..
Possibly, but who cares about that?
>
>Oil fired new aga, after 18 months suddenly - or possibly gradually -
>running cooler and cooler according to thermometer.
Is this just when idling? Does it take a long time to recover after
a large use of heat?
>
>The electrical stat seems to be working - I have stuck it manually on
>'overdrive' but it still is running at idle basically?
The gas one has a modulating gas control which steps up the firing
rate as you start to use more heat. Presumably the oil one has a
similar mechanism?
>
>Any ideas before I call in the engineer?
I believe the manufacturer's recommended service interval for an oil
burner is six months. Is it possible that it simply needs a good
clean? For my gas one this is the lion's share of the service
procedure.
.andy
To email, substitute .nospam with .gl
Andy Hall
wrote:
How would you measure efficiency anyway? On my gas one, the steady
state burn rate is about 700W. We have a conventional flue exiting
through a special ridge tile. By the time the flue enters the roof
space it is almost cold so almost all of the heat is released either
by the appliance itself or the flue within the envelope of the house.
In that sense there is very little waste of heat during the 9 months
of the year when heating is required. In effect this amounts to heat
that the CH does not need to provide.
One can argue, therefore, that from an energy efficiency perspective,
this is a better scenario than the typical, poorly insulated oven and
hob arrangements that require the user to open the windows and waste
the heat because of overheating of the kitchen.
I would expect the oil fired unit to be similar from the perspective
of what is released into the room, but possibly slightly more through
the flue since AIUI oil flues run hotter.
IMM
"Andy Hall" <an...@hall.nospam> wrote in message
news:or4iiv0hgepbnlkr5...@4ax.com...
> >>> Sadly, the only solution is to throw it out. get yourself something
> >>> decent and efficient.
> >>
> >> <OMG> - I think this is the second time I've agreed with you in
> >> as many weeks. I'm really starting to worry.
> >>
> >> I know Agas have a massive following, and that people love them
> >> to death and swoon over them, but I find them to be horrible,
> >> loathsome things.
> >>
> >
> >Yea this one isn't even self cleaning! ;-)
> >
> >Anyone know the efficiency of an oil fired Aga?
>
> How would you measure efficiency anyway?
> On my gas one,
You have one too? Oh my God!!!!
> the steady state burn rate is about 700W.
> We have a conventional flue exiting
> through a special ridge tile. By the time
> the flue enters the roof
> space it is almost cold so almost all
> of the heat is released either
> by the appliance itself or the flue within
> the envelope of the house.
And in summer that is what you don't want.
> In that sense there is very little waste of heat during the 9 months
> of the year when heating is required. In effect this amounts to heat
> that the CH does not need to provide.
>
> One can argue, therefore, that from an energy efficiency perspective,
> this is a better scenario than the typical, poorly insulated oven and
> hob arrangements that require the user to open the windows and waste
> the heat because of overheating of the kitchen.
A heat recovery fan is the way for that.
Grunff
> How would you measure efficiency anyway?
The way I see it there are two efficiencies involved:
[1] The efficiency with which the Aga converts the fuel's energy
to heat.
and
[2] The efficiency of the way in which this heat is released
into the house.
I suspect (but have no numbers) that on [1], an Aga will come a
little, but not by much, lower than a high pressure oil boiler.
As for [2], it'll depend a lot on the time of year, as you point
out. In the colder months, the heat output into the room is a
useful contribution to the CH. In the summer, it's a PITA.
I would guess that overall, Agas would come in as being a bit
less efficient than a cooker/CH setup, but not by so much that
it would cause anyone to worry too much.
What I object to is that they're high maintenance, difficult to
clean, extremely expensive, and take up an inordinately large
amount of space for the functionality they provide. I'll stick
to my oil boiler and fan oven ;-)
--
Grunff
Andy Hall
>
>"Andy Hall" <an...@hall.nospam> wrote in message
>news:or4iiv0hgepbnlkr5...@4ax.com...
>> On Thu, 31 Jul 2003 08:23:55 -0400, CJ <chris....@cwfi.co.fk>
>> wrote:
>
>> >>> Sadly, the only solution is to throw it out. get yourself something
>> >>> decent and efficient.
>> >>
>> >> <OMG> - I think this is the second time I've agreed with you in
>> >> as many weeks. I'm really starting to worry.
>> >>
>> >> I know Agas have a massive following, and that people love them
>> >> to death and swoon over them, but I find them to be horrible,
>> >> loathsome things.
>> >>
>> >
>> >Yea this one isn't even self cleaning! ;-)
>> >
>> >Anyone know the efficiency of an oil fired Aga?
>>
>> How would you measure efficiency anyway?
>> On my gas one,
>
>You have one too? Oh my God!!!!
I've never made a secret of that.
>
>> the steady state burn rate is about 700W.
>> We have a conventional flue exiting
>> through a special ridge tile. By the time
>> the flue enters the roof
>> space it is almost cold so almost all
>> of the heat is released either
>> by the appliance itself or the flue within
>> the envelope of the house.
>
>And in summer that is what you don't want.
It's of no consequence.
>
>> In that sense there is very little waste of heat during the 9 months
>> of the year when heating is required. In effect this amounts to heat
>> that the CH does not need to provide.
>>
>> One can argue, therefore, that from an energy efficiency perspective,
>> this is a better scenario than the typical, poorly insulated oven and
>> hob arrangements that require the user to open the windows and waste
>> the heat because of overheating of the kitchen.
>
>A heat recovery fan is the way for that.
>
Only if you want to put the heat somewhere else in the house.
>
>
>
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>Outgoing mail is certified Virus Free.
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>
.andy
Andy Hall
>Andy Hall wrote:
>
>> How would you measure efficiency anyway?
>
>The way I see it there are two efficiencies involved:
>
>[1] The efficiency with which the Aga converts the fuel's energy
>to heat.
>
>and
>
>[2] The efficiency of the way in which this heat is released
>into the house.
>
Reasonable.
>
>I suspect (but have no numbers) that on [1], an Aga will come a
>little, but not by much, lower than a high pressure oil boiler.
I don't see why, particularly, but OK.
>
>As for [2], it'll depend a lot on the time of year, as you point
>out. In the colder months, the heat output into the room is a
>useful contribution to the CH. In the summer, it's a PITA.
That depends on the size and design of the house. It never causes us
a problem.
>
>I would guess that overall, Agas would come in as being a bit
>less efficient than a cooker/CH setup, but not by so much that
>it would cause anyone to worry too much.
>
>What I object to is that they're high maintenance, difficult to
>clean, extremely expensive, and take up an inordinately large
>amount of space for the functionality they provide.
I disagree on most of those points.
Maintenance on a gas burner is once a year and is an easy DIY job for
the competent. On an oil one every six months, but AIUI many oil
burning appliances need that interval as well so it comes with the
turf.
Cleaning is really easy. The majority of things cooked in the ovens
are done so either covered or at a low temperature where there is not
splashing. In the roasting and baking ovens, splashes are carbonised
relatively quickly and can be swept out. The enamelled top can
easily be wiped or better, cleaned with a steam cleaner very quickly
and effectively. There is no messing around with caustic soda and
other chemicals.
There's loads of functionality. Apart from the flexible and excellent
cooking there is the ability to warm crockery (I believe that serving
hot food onto cold plates should be a capital offence), warming
ingredients, drying herbs, warming clothes, airing clothes and caring
for sick animals. My cats, who spend 23 hours a day in front of the
Aga in the winter would also suggest that it's a pussy magnet.
>I'll stick
>to my oil boiler and fan oven ;-)
Grunff
>>What I object to is that they're high maintenance, difficult to
>>clean, extremely expensive, and take up an inordinately large
>>amount of space for the functionality they provide.
>
>
> I disagree on most of those points.
I wouldn't have expected you not to. I have many friends in
exactly the same category - the Aga is a central feature in
their dwellings, and they love it. And you simply can't change
their minds (even if there was any point in doing so).
So fair enough - you keep your Aga and I'll keep my setup ;-).
--
Grunff
The Natural Philosopher
About 90% at heating the kitchen :)
The Natural Philosopher
>
> Maintenance on a gas burner is once a year and is an easy DIY job for
> the competent. On an oil one every six months, but AIUI many oil
> burning appliances need that interval as well so it comes with the
> turf.
>
This ones dione 18 months without being touched. Any ideas what might
need attention and why?
It is supposed to be serviced annually I think.
I am wondering if teh wick has burned down - but that shouldn't make any
difference, since it works on vapour. Its like the oil flow is
restricted somehow.
Oh well.
> Cleaning is really easy. The majority of things cooked in the ovens
> are done so either covered or at a low temperature where there is not
> splashing. In the roasting and baking ovens, splashes are carbonised
> relatively quickly and can be swept out. The enamelled top can
> easily be wiped or better, cleaned with a steam cleaner very quickly
> and effectively. There is no messing around with caustic soda and
> other chemicals.
Hmm. I disagree. I give mine regular caustc doses tio clear congealed fat.
Do the same on the ceramic hob cookers as well. Yes, I have three cookers :)
>
> There's loads of functionality. Apart from the flexible and excellent
> cooking there is the ability to warm crockery (I believe that serving
> hot food onto cold plates should be a capital offence), warming
> ingredients, drying herbs, warming clothes, airing clothes and caring
> for sick animals. My cats, who spend 23 hours a day in front of the
> Aga in the winter would also suggest that it's a pussy magnet.
>
Ive got some of those too .
All have their place. I'd say that teh aga is probably more efficient as
a room haeter than teh boiler, but of course its not everywhere. At this
tiome of year its a bit hot, and I would have switched it off only I
couldn't be arsed.
Andy Hall
Deal.
IMM
"The Natural Philosopher" <a@b.c> wrote in message
Even in summer.
IMM
"Andy Hall" <an...@hall.nospam> wrote in message
For the cost of an AGA you could have gone on cruise.
Richard
"The Natural Philosopher" <a@b.c> wrote in message
> Andy Hall wrote:
>
> >
> > Maintenance on a gas burner is once a year and is an easy DIY job for
> > the competent. On an oil one every six months, but AIUI many oil
> > burning appliances need that interval as well so it comes with the
> > turf.
> >
>
>
> This ones dione 18 months without being touched. Any ideas what might
> need attention and why?
Yes the oilways and the burner pot are blocked with carbon from a slow build
up as the hot oil degades.
> It is supposed to be serviced annually I think.
No 6 months is the proper service interval.
> I am wondering if teh wick has burned down - but that shouldn't make any
> difference, since it works on vapour. Its like the oil flow is
> restricted somehow.
If you have your Aga serviced professionally new wicks are usually fitted
each time. This is overkill , a set of wicks can last for several years.
They are only really necessary to light the burner and get it to vapourising
temperature.
If you have not got a manual I suggest you get a copy.
Richard.
> Oh well.
>
>
The Natural Philosopher
> "Andy Hall" <an...@hall.nospam> wrote in message
> news:l8fiivoa7l80k1v12...@4ax.com...
>
>>On Thu, 31 Jul 2003 16:21:28 +0100, Grunff <gru...@ixxa.com> wrote:
>>
>>
>>>Andy Hall wrote:
>>>
>>>
>>>>>What I object to is that they're high maintenance, difficult to
>>>>>clean, extremely expensive, and take up an inordinately large
>>>>>amount of space for the functionality they provide.
>>>>>
>>>>
>>>>I disagree on most of those points.
>>>>
>>>I wouldn't have expected you not to. I have many friends in
>>>exactly the same category - the Aga is a central feature in
>>>their dwellings, and they love it. And you simply can't change
>>>their minds (even if there was any point in doing so).
>>>
>>>So fair enough - you keep your Aga and I'll keep my setup ;-).
>>>
>>Deal.
>>
>
> For the cost of an AGA you could have gone on cruise.
>
I went on a cruise once in 1963, it was vile beyond belief.
You would enjoy it pronably. I bet you go to Butlins every year.
For teh cost of the Aga I could have gone on Safari. Never mind. I'll go
anyway.
@my_last_name.org.uk Richard Caley
ah> How would you measure efficiency [of an aga] anyway?
The Trollope is the SI unit of extra marital affairs per chapter.
IMM
"The Natural Philosopher" <a@b.c> wrote in message
> IMM wrote:
>
> > "Andy Hall" <an...@hall.nospam> wrote in message
> > news:l8fiivoa7l80k1v12...@4ax.com...
> >
> >>On Thu, 31 Jul 2003 16:21:28 +0100, Grunff <gru...@ixxa.com> wrote:
> >>
> >>
> >>>Andy Hall wrote:
> >>>
> >>>
> >>>>>What I object to is that they're high maintenance, difficult to
> >>>>>clean, extremely expensive, and take up an inordinately large
> >>>>>amount of space for the functionality they provide.
> >>>>>
> >>>>
> >>>>I disagree on most of those points.
> >>>>
> >>>I wouldn't have expected you not to. I have many friends in
> >>>exactly the same category - the Aga is a central feature in
> >>>their dwellings, and they love it. And you simply can't change
> >>>their minds (even if there was any point in doing so).
> >>>
> >>>So fair enough - you keep your Aga and I'll keep my setup ;-).
> >>>
> >>Deal.
> >>
> >
> > For the cost of an AGA you could have gone on cruise.
> >
>
>
> I went on a cruise once in 1963,
Did the ship have sails?
> it was vile beyond belief.
Ever seen the new cruise ships?
> You would enjoy it pronably.
> I bet you go to Butlins every year.
Never been. I believe they are very good and the "villages" are top rated
with superb service, facilities etc.
> For teh cost of the Aga I could have gone on Safari. Never mind. I'll go
> anyway.
With an AGA
The Natural Philosopher
> "The Natural Philosopher" <a@b.c> wrote in message
> news:3F293CE1.3050200@b.c...
>
>>Andy Hall wrote:
>>
>>
>>>Maintenance on a gas burner is once a year and is an easy DIY job for
>>>the competent. On an oil one every six months, but AIUI many oil
>>>burning appliances need that interval as well so it comes with the
>>>turf.
>>>
>>>
>>
>>This ones dione 18 months without being touched. Any ideas what might
>>need attention and why?
>>
>
>
> Yes the oilways and the burner pot are blocked with carbon from a slow build
> up as the hot oil degades.
>
Is that just the sort of maze like tray that the oil pours into before
getting vaporised? That's not hard to clean...
Frankly if its a mornings job, I'll just shut the thing down and do it.
>
>>It is supposed to be serviced annually I think.
>>
>
> No 6 months is the proper service interval.
>
>
I'll take that as read.
>
>>I am wondering if teh wick has burned down - but that shouldn't make any
>>difference, since it works on vapour. Its like the oil flow is
>>restricted somehow.
>>
>
> If you have your Aga serviced professionally new wicks are usually fitted
> each time. This is overkill , a set of wicks can last for several years.
> They are only really necessary to light the burner and get it to vapourising
> temperature.
Yes, which is why I thought 'can't be that'
>
> If you have not got a manual I suggest you get a copy.
Where from?
>
> Richard.
>
>>Oh well.
>>
>>
>>
>
>
Andy Hall
>> >
>> >So fair enough - you keep your Aga and I'll keep my setup ;-).
>>
>> Deal.
>
>For the cost of an AGA you could have gone on cruise.
>
>
I can do both. However I wouldn't choose a cruise or any other form
of vacation where somebody else does the organisation. From bitter
experience I only trust two people to make my travel arrangements -
one is me and the other is an excellent person at a business travel
agent that I have used for 20 years.
The Natural Philosopher
> In article <or4iiv0hgepbnlkr5...@4ax.com>, Andy Hall (ah) writes:
>
> ah> How would you measure efficiency [of an aga] anyway?
>
> The Trollope is the SI unit of extra marital affairs per chapter.
>
>
:-)
One of the things about an aga, is teh lower oven is almost impossible
toi burn things in, so loads of shit home counties cooks love em.
"I'll just pop hubby's dinner in the warming oven while we go up for a
shag, Vicar"
Andy Hall
wrote:
or "I can't do it but the Aga can".
The Aga can..... Oh, never mind.
Toby Sleigh
"Richard" <hawkins...@DIGITbtinternet.com> wrote in message
news:bgb213$psr$1...@hercules.btinternet.com...
>
>
> This is a DIY NG. so why are you considering calling an engineer out to
your
> Aga? Once you know how to diagnose and service an Aga the exercise is
> simplicity itself.
>
> Richard.
>
>
I dismantled our gas 4 oven a few weeks ago as the kitchen was being
rebuilt.
Took lots of piccies at the time but any advice & tips for re-assembling in
a few weeks time would be most welcome.
Toby
The Natural Philosopher
> "The Natural Philosopher" <a@b.c> wrote in message
I bet you go to Butlins every year.
>>
>
> Never been. I believe they are very good and the "villages" are top rated
> with superb service, facilities etc.
>
Need one say more?
>
>>For teh cost of the Aga I could have gone on Safari. Never mind. I'll go
>>anyway.
>>
>
> With an AGA
Mo, with a land rover probably.
>
The Natural Philosopher
> "Richard" <hawkins...@DIGITbtinternet.com> wrote in message
> news:bgb213$psr$1...@hercules.btinternet.com...
>
>>
>>This is a DIY NG. so why are you considering calling an engineer out to
>>
> your
>
>>Aga? Once you know how to diagnose and service an Aga the exercise is
>>simplicity itself.
>>
>>Richard.
>>
>>
>>
> Any of you lot ever dismantled & moved an AGA.?
No, but I watched someone build ours from parts...
> I dismantled our gas 4 oven a few weeks ago as the kitchen was being
> rebuilt.
> Took lots of piccies at the time but any advice & tips for re-assembling in
> a few weeks time would be most welcome.
Get a pro in m8 :-)
All that repacking with insulatuon and gentle filing to get teh parts to
fit.
Mind you with gas you don't have to check oil flow etc etc.
> Toby
>
>
>
Richard
"Toby Sleigh" <t...@sleigh.freeserve.co.uk> wrote in message
news:bgbk2n$n9keq$1...@ID-9589.news.uni-berlin.de...
I have only reassembled a few oil fired Agas so my experience of gas fired
beasts is zero.
However there are many points of similarity and so I will pass on a few
tips.
The vertical rods that secure the top to the rest of the structure should be
firmly locked at the bottom plate.
Six lengths,or four if it is a two oven model, of 10mm copper pipe, about 4
to 6 inches, pushed onto the rods makes the alignment with the holes in the
Aga top a simple matter.Although two or even three people makes lighter
work!
Don't be in a hurry to re- stuff the insulation until you have adjusted both
the hot plates to be absolutely level and at equal heights. Having done the
levelling put the top in place and ensure that each hot plate is below it's
surround by the thickness of a coin . This is to allow for expansion at
operating temperatures. The objective is to have the plates level with or a
tiny amount above the surround at working temperature. Note that there are
adjusting screws in the top of the hot oven.
Remember to fit the thermostat and oven sensor before you finally fit the
top. It is possible to replace and re-fit the thermostat with the top in
place but this will not apply in your case.
Get yourself a detailed assembly/Installation manual from the Aga/Rayburn
people. I have always found them most helpful.
Take you time and whatever the insulation type wear a mask !
Toby Sleigh
"Richard" <hawkins...@DIGITbtinternet.com> wrote in message
> Lots of good stuff
>
Richard thanks for that, just the sort of info I'm after. I will get a
manual, assuming they sell it to all & sundry.
TNP's suggestion was fairly sound apart from the fact that the pro's I have
phoned all start from 500gbp plus vat +this & that + much tutting about
probably cost more due to suspect disassembly. You could almost hear the
cash registers chinging.
Toby
Andy Hall
I have a bunch of pictures of the assembly of a 4 oven gas model if
they would be of use to you.
From memory, one of the main issues is adjusting the threaded rods at
each stage such that the component being supported is level.
If you have removed the insulation from the left hand oven module, you
may need to install fresh. Apparently when new the material is
coated in lanolin to allow it to be stuffed into the spaces. That is
driven off on first firing and the material is then not easy to remove
and replace.
Depending on its condition it may be worth replacing the Vermiculite
in the main body.
One final point is to make sure that the surfaces of the plates are
approximately 3mm below the cast rings surroiunding them when the unit
is cold. When hot, expansion brings them up to the level of the
ring.
To be honest, I would suggest having somebody from the dealer put it
back together.
geoff
writes
>No doubt IMM will delight in this one..
>
>Oil fired new aga, after 18 months suddenly - or possibly gradually -
>running cooler and cooler according to thermometer.
>
>The electrical stat seems to be working - I have stuck it manually on
>'overdrive' but it still is running at idle basically?
>
>Any ideas before I call in the engineer?
>
Phone Aga (in Telford) and ask for technical support. They are quite
helpful
--
geoff
John
"The Natural Philosopher" <a@b.c> wrote in message
> No doubt IMM will delight in this one..
>
> Oil fired new aga, after 18 months suddenly - or possibly gradually -
> running cooler and cooler according to thermometer.
>
> The electrical stat seems to be working - I have stuck it manually on
> 'overdrive' but it still is running at idle basically?
>
> Any ideas before I call in the engineer?
>
When was it last serviced?
I suspect you have a coking up problem in the burner oilways and possibly
the burner underfeed tube. This requires a strip down and clean out
together with the remainder of the service schedule works.
--
Please note antispam measures - do not hit reply
Horse sense is what horses have that makes them not bet on people - W.C.
Fields
Regards,
John
Maximus Glutimus
m.holley
"The Natural Philosopher" <a@b.c> wrote in message
news:3F28FAE4.3090405@b.c...
>
> Oil fired new aga, after 18 months suddenly - or possibly gradually -
> running cooler and cooler according to thermometer.
>
> The electrical stat seems to be working - I have stuck it manually on
> 'overdrive' but it still is running at idle basically?
>
> Any ideas before I call in the engineer?
Greetings,
A usefil nugget gleaned froma an Aga engineer: re oil Aga's.
If summer you may notice that your Aga runs hotter than in Winter for a set
thermostat setting. Apparently this is because in Summer the oil is warmer
and hence more "liquid" and runs through the feed pipes faster, so more oil
to the burner. In winter the oil is thicker and so flow is slower and hence
temp is lower.
regarsd M
Richard
"m.holley" <pr...@bath.ac.uk> wrote in message news:HIxyn...@bath.ac.uk...
came up with is a load of codswallop. The thermostat that controls the
high/low flame modulation is installed within the house ,usually screwed to
the Aga itself. It is in a room temperature environment but in any case the
temperature of an Aga or any other such device is controlled by an internal
thermostat which I am sure you will eventually realise does not care if it
is Summer or Winter outside.
Richard.
John
"Richard" <hawkins...@DIGITbtinternet.com> wrote in message
NOT ALL Agas have thermostatic control. Many of the early models simply
regulated the oil input flow via a needle valve from a constant head float
chamber into the burner casting.
Mind you I think the explanation whilst it "may" have some theoretical
physics basis is getting a bit near the edge of the bullshit envelope since
the viscosity of kerosine is not going to change all that much over the
range of temperatures at the input to the float chamber (BM Box to those
folks who have one). Possible other related factors by probable truth are
1. Human impression of heat/humidity
2. Variation of the metal clearances of the internals of the BM Box due to
expansion allowing marginal variation in flow (non thermostat type)
3. Reduction of thermal gradient from inside cooker to room temperature
giving less "losses" and thus higher oven temperature
4. any other things you can imagine when asked a question you don't have
the answer for but don't want to admit it to customer
Richard
"John" <AS-Bo1...@btinternet.com> wrote in message
news:bggke0$jvj$1...@hercules.btinternet.com...
I would be very interested to which "early models" you refer that have no
thermostat. Even the very early solid fuel to oil conversions had low/high
flame modulation controlled by a thermostat. Whether the burn rate is
controlled by a needle valve or a metered slit a thermostat has always been
the means of control.What is your source of information on Agas without
thermostats ? I find it hard to believe that such bits of kit have ever
been produced. However I am always willing to learn.
For your information the original solid fuel Agas had thermostats which
controlled the airflow entering the fire box and consequently matched the
heat supplied ,over time, with the cooking requirements. You are now saying
that some early oil fired models did away with thermostats. I find that hard
to believe so convince me.:-)
Richard.
John
"Richard" <hawkins...@DIGITbtinternet.com> wrote in message
>
SNIP
>
> I would be very interested to which "early models" you refer that have
no
> thermostat. Even the very early solid fuel to oil conversions had
low/high
> flame modulation controlled by a thermostat. Whether the burn rate is
> controlled by a needle valve or a metered slit a thermostat has always
been
> the means of control.What is your source of information on Agas without
> thermostats ? I find it hard to believe that such bits of kit have ever
> been produced. However I am always willing to learn.
I'm sorry but you are wrong in the scope of your statement. I reiterate
that NOT ALL Agas have thermostats. I know this because I spent a great
deal of time servicing many in my locality when I worked for the area Shell
Oil agent. Hands on experience of a number of units is what I speak from
>
> For your information the original solid fuel Agas had thermostats which
> controlled the airflow entering the fire box and consequently matched the
> heat supplied ,over time, with the cooking requirements. You are now
saying
> that some early oil fired models did away with thermostats. I find that
hard
> to believe so convince me.:-)
>
Most of the solid fuel to oil conversions prior to about 1980 that I worked
on relied on a rotating knob on top of the BM float box which was an
extension of the needle valve spindle. (You may have regarded this as a
thermostat?) In all the cases I can recall, the removal of the solid fuel
burning apparatus included the simultaneous removal of the "flap" which
controlled the air supply. This was required since a vapourising oil burner
requires sufficient (excess) combustion air to prevent carbon monoxide
formation and interference with the airflow has high risk of improper
combustion.
I don't deal with Agas now as age has given me a lower back problem
which is exacerbated by trying to lift the cast iron lumps which form the
hotplates out of the cooker to gain access to the burner. However, I can
definitely assure you that I am correct in what I say about not all Agas
having thermostatic control. Later models and some of those manufactured as
oil fired rather than conversions from solid fuel were indeed fitted with
an electrically operated thermostat which used a low voltage transformer, a
normally closed electrical thermostat which opened on temperature rise and
a heater element which caused a bimetal strip to deflect and operated on a
pushrod which opened or closed the needle valve.
If you are really interested I am sure Aga will confirm what I have
told you
Richard
Your first post on the subject of aga temperatures varying with the time of
year was stated as a generality and was plainly incorrect which is why I
felt it necessary to post my comment. You also said that you got this
"nugget of information" from an aga engineer. Was this in conversation with
an engineer at the Aga headquarters or was it from someone who held himself
out to be an Aga engineer in the field? Because which ever it was either he
was talking rubbish or you have a poor recollection of what was said.
In your further posts it now is revealed that you are very experienced in
the servicing and maintenance of Agas and that the lack of thermostats only
applied to some conversions to previously solid fuelled Agas prior to the
1980s If you knew this to be so why did you make the fallacious post that
appeared to apply to Agas generally? Or did I miss a smiley at the end of
you post ?
In about 1960 my parents had a solid fuel to oil converted Aga and even then
it was provided with an electric controlbox that had red and green lights to
show the high or low flame state and guess what, this was controlled by a
thermostat. this pre dates you reference by a mere 20 years.
I am not familiar with the BM regulator to which you refer and I am not
going to waste my time to follow it up with the Aga/Rayburn people because I
am quite sure the burning rate was thermostatically controlled.
The actual thermostat may not have been in the current form of a sealed vial
in the oven.There were I believe some early conversions which used a
bi-metallic strip attached to the structure next to the fire box they were
none the less thermostats.
BTW your reference to needle valves in later models and purpose made oil
fired versions is somewhat inaccurate. The metering slit operating in a tube
need an enormous leap to be described as a needle valve. It would be
impossible to prick yourself with it for a start!
One final thought, how did the user of a thermostatless Aga manage to avoid
thermal runaway or maintain any sort of control over cooking temperatures.
What would happen if they were away from home for say 24 hours, planned or
unplanned, ?
Richard.
The Natural Philosopher
Shame. Its ruinning cooler :-)
> regarsd M
>
>
>
>
The Natural Philosopher
I will confirm teh veracity of this. Oil convesrions and early oil agas
had no feedback, but mechanical regulators.
Mine has an electrical one however, which is still functioning.
The Natural Philosopher
Agas on oil are set up for two flow rates - one is the low flow rate,
designed to maintain the minimum useable temperature, and the other is
max flow rate, designed to get the aga as hot as it ever needs to be.
They toggle between the two under thermostatic control, and can be
manually overridden.
I have manually overridden mine, but it still runs too cool :(
All that having the high flow rate set will do is run the aga at its max
useable temperature. They don't do runaway, any more than any other
paraffin stove does.
>
> Richard.
>
>
>
>
John
"Richard" <hawkins...@DIGITbtinternet.com> wrote in message
You seem to be confused about the attribution of who posted the initial
posts?
I suggested in my post that there was a high bullshit factor in the "Aga
Enginners" explanation :-)
>
> In your further posts it now is revealed that you are very experienced in
> the servicing and maintenance of Agas and that the lack of thermostats
only
> applied to some conversions to previously solid fuelled Agas prior to the
> 1980s If you knew this to be so why did you make the fallacious post
that
> appeared to apply to Agas generally? Or did I miss a smiley at the end of
> you post ?
See above - you will see that my posts said NOT ALL Agas came under the
banner of thermostatic controlled units. This by definition does not
exclude those that do but please try to understand that ther are many that
do not, especially those that vary in temperature during the summer (even
if only in their owners "impressions")
>
> In about 1960 my parents had a solid fuel to oil converted Aga and even
then
> it was provided with an electric controlbox that had red and green lights
to
> show the high or low flame state and guess what, this was controlled by a
> thermostat. this pre dates you reference by a mere 20 years.
Presumably this is an early version of the auxiliary low voltage control
which I described. The ones I met did not have the lights but I have
already gone over their methodology
>
> I am not familiar with the BM regulator to which you refer and I am not
> going to waste my time to follow it up with the Aga/Rayburn people
because I
> am quite sure the burning rate was thermostatically controlled.
Please try to understand that there are others outside your experience of
one unit which do not in fact comply with your expectations. Some I agree
may have done so.
> The actual thermostat may not have been in the current form of a sealed
vial
> in the oven.There were I believe some early conversions which used a
> bi-metallic strip attached to the structure next to the fire box they
were
> none the less thermostats.
The original solid fuel thermostat damper indeed had a bimetal strip which
moved the position of the air damper but as I explained before restricting
air to a vapourising burner is dangerous and this was not used with
converted units. I am quite prepared to believe that there is a possibility
that somewhere along the line a few models may have been tried with a
bimetallic strip acting on the needle valve which is what was done further
down the line with the hybrid electrical thermostat system which I
described. A heater element being attacched to the bimetal to cause it to
deflect.
>
> BTW your reference to needle valves in later models and purpose made oil
> fired versions is somewhat inaccurate. The metering slit operating in a
tube
> need an enormous leap to be described as a needle valve. It would be
> impossible to prick yourself with it for a start!
OK for pedantrys sake it is a metering slit which is in a tube which slides
into another tube so opening or covering the "clear" length of slit or
orifice but in the context of easy explanation for others to read I think
describing it as a needle valve is normally adequate insofar as the further
the inner tube is pressed down the less aperture is presented to the oil
flow although this desription takes significantly longer to write and is
perhaps not as succinct!
Suffice it to say we are talking about the beige coloured, ovaloid cylinder
shaped control box bearing the "trip" lever and the flame control knob etc
fitted to the Aga range along with a myriad other vapourising burner
appliance for dozens of years here?
>
> One final thought, how did the user of a thermostatless Aga manage to
avoid
> thermal runaway or maintain any sort of control over cooking
temperatures.
> What would happen if they were away from home for say 24 hours, planned
or
> unplanned, ?
One of the frequent complaints from customers after a service when the
oilways had been cleaned out and the flow was back up to standard was of
"overheating" although this was one of those "cooks" impressions rather
than one supported by thermometer measurement. The BM box was (is) a clever
bit of kit insofar as it contained in one box a fuel filter, overfilling
cut off device (if the float control suffered a bit of grit on the seat
etc), fusible firestop shut off, fuel level control for constant head feed
to the metering valve, low flow limit stop and high flow limit stop. The
low and high flow limits were set according to makers specifications and
the high flow or high fire setting was designed to avoid thermal damage to
the device if not to the cakes and Yorkshire Puddings. The housewife soon
came to learn to run the Aga on low for most of its life and turn the
burner up in good time for baking day
The system as such worked just fine for many years even if it was a bit
crude by a modern control engineers standards. The lack of thermostatic
control was never a problem to the early manned burning kit such as on
factory boilers, furnaces, steam locomotives, warships etc. All you needed
was a decent stoker with a shovel and a strong back on the big uns. I know
of a sinter hood in Tilbury which burns waste oil even today and is
entirely regulated by the operators adjusting gate valves in the oil suply
to the burner nozzles. The thermal mass of the process allows wide(ish)
tolerance of the flame to be taken care of without rapid oscillation of the
temperature, exactly as is the case with the big lumps of cast iron in an
Aga
Richard
"The Natural Philosopher" <a@b.c> wrote in message
The main reason that your Aga runs too cool has been pointed out to you in
several previous posts. 18 months between services is far too long. The hot
part of the oil supply pipe will be clogged with carbonised oil as will the
burner oilways and the vaporising pot in the centre of the burner. Even if
you override the control valve the burn rate will be too slow to bring the
cooker up to the proper operating temperature.
Your analogy with "any other paraffin stoves" is not relevant. A paraffin
stove radiates or convects away the burner heat as fast as it is generated
so there is no thermal runaway and so they don't need to be fitted with a
thermostat. An Aga operates in a somewhat different mode. It is an insulated
heat storage device. When properly installed and regulated the low flame
setting supplies enough heat to maintain the oven temperature some several
degrees below the optimum. This is defined by the right hand edge of the
black sector on the temperature gauge markings. The high flame setting is
such that heat is supplied at a rate that is greater than can be dissipated
by heat environmental heat losses. Consequently the temperature rises until
the thermostat setting is met, this is normally at the index line on the
temperature gauge. Without an effective thermostat the temperature would
continue to rise into the Red area until the overheat cut-off stopped the
oil supply.
I must point out that I am talking about a properly installed and regulated
Aga. I have seen many examples where the low and high oil flow rates have
been incorrectly set. This can of course give rise to several undesirable
effects but with a little knowledge and patience can be easily corrected.
David
> No doubt IMM will delight in this one..
>
> Oil fired new aga, after 18 months suddenly - or possibly gradually -
> running cooler and cooler according to thermometer.
>
> The electrical stat seems to be working - I have stuck it manually on
> 'overdrive' but it still is running at idle basically?
>
> Any ideas before I call in the engineer?
God I get sick of thread smart ***es and thread hijackers.
Hey people if you want to dribble, go somewhere else.
If you want to ask another question, start your own thread.
Rant over, back to the Aga servicing.
I'm not an expert but this is what I do to my own 5yr old oil Aga.
If your burner/pipes dont match the description below, you may need to
adapt the process.
1. Turn it off and let it cool (instructions inside burner door)
2. Disconnect the oil line at the elbow. Put a rag underneath to catch
any drips. Be careful of the elbow/join as you disconnect it.
3. Slide out the whole burner unit on its plate.
4. Note the orientation of the lid and the burner rings as you lift
them off.
5. Lift the lid off the oil bowl and you should find it coked up ie.
you can't see the inlet hole.
6. The wick may look tired but it will still work fine.
7. Remove the pipe (not the pipe fitting) from the bottom of the bowl.
Decoke the bowl, the hole (i use a small drillbit for the hole) and
the bowl end of the pipe if necessary. A vacuum cleaner helps clean
away the bits of carbon as you loosen them.
8. Reassemble and follow the intstructions on the door to light.
9. Don't alter the levelling screws on the burner plate - the
installer will have set the plate level.
It may take you a couple of hours the first time you do it. Next time
it'll take you less than an hour.
Good luck.
jacob
.A proper gas cooker is a fraction of the cost, more or less service
free for life, and does everything that an aga does but better,
quicker etc, without heating the kitchen excessively. And you don't
need to buy special very expensive pans, kettles etc.
cheers
Jacob