Drayton TRVs: MAX not high enough
RobertL
but i find that the MAX setting is too low in less well-insulated
rooms. i.e. the room tempertaure is below what I would like (23C)
but the TRV is closing while the thermostat still calls for more heat.
has anyone else encountered this? Is it because I have the rads top
fed with the TRV on the inlet and therefore sensing a lot of heat
directly from the rad? Is it because I have too little rad
capacirty so the system is running with a high max water temperature
(85C)?
The heads seem to move about 1mm for each step in the temperature
setting (1:6(max)), with a total range of 6mm. Perhaps I could insert
a 2mm thick spacer to raise the sensor higher.
Any well-known solutions?
Robert
David Hansen
<rober...@yahoo.com> wrote this:-
>I have fitted Drayton TRVs on most rads like these:
>
>http://www.screwfix.com/prods/26100/Plumbing/Radiator-Valves/Drayton-TRV4-White-Chrome-TRV-15mm-Angled
>
>but i find that the MAX setting is too low in less well-insulated
>rooms. i.e. the room tempertaure is below what I would like (23C)
>but the TRV is closing while the thermostat still calls for more heat.
Is the thermostat in the same room as radiators with TRVs?
23C is very hot.
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/ukpga_20000023_en_8#pt3-pb3-l1g54
slider
"David Hansen" <SENDdavi...@spidacom.co.uk> wrote in message
news:c5pfh5l93411pejjv...@4ax.com...
Just take the head off the TRV and let it remain fully open. I do this in
our living room.
> 23C is very hot.
Our thermostat in the hallway is never below 25�C
David Hansen
<sli...@slide.com> wrote this:-
>> 23C is very hot.
>
>Our thermostat in the hallway is never below 25�C
That is even hotter, but is there a radiator nearby?
slider
There is a small radiator about 4 foot from the thermostat. It's can open
staircase, think most of the heat rises upstairs.
...
> I have fitted Drayton TRVs on most rads like these:
>
>
> but i find that the MAX setting is too low in less well-insulated
> rooms. i.e. the room tempertaure is below what I would like (23C)
> but the TRV is closing while the thermostat still calls for more heat.
>
> has anyone else encountered this? Is it because I have the rads top
> fed with the TRV on the inlet and therefore sensing a lot of heat
> directly from the rad? Is it because I have too little rad
> capacirty so the system is running with a high max water temperature
> (85C)?
>
> The heads seem to move about 1mm for each step in the temperature
> setting (1:6(max)), with a total range of 6mm. Perhaps I could insert
> a 2mm thick spacer to raise the sensor higher.
>
> Any well-known solutions?
>
> Robert
Turn down the trv in the room where the electrically controlled
thermostat is obviously!
RobertL
But it's not that the boiler shuts off prematurely. It's that the
cold room rad TRV turns off the flow at too low a temperature.
thanks for the discussion anyway folks.
Robert
Roger Mills
RobertL <rober...@yahoo.com> wrote:
>
> But it's not that the boiler shuts off prematurely. It's that the
> cold room rad TRV turns off the flow at too low a temperature.
>
> thanks for the discussion anyway folks.
>
>
> Robert
On its Max setting, it shouldn't cut off the flow until the room temperature
reaches about 27 degC. As others have said, if that isn't hot enough, remove
the head and just leave the valve fully open.
What is the orientation of the head? If it's vertical, and if you think it's
being heated unduly by the rad itself, you could try fitting it the other
way round, so that it is horizontal.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!
Roger Mills
> In an earlier contribution to this discussion,
> RobertL <rober...@yahoo.com> wrote:
>
>>
>> But it's not that the boiler shuts off prematurely. It's that the
>> cold room rad TRV turns off the flow at too low a temperature.
>>
>> thanks for the discussion anyway folks.
>>
>>
>> Robert
>
> On its Max setting, it shouldn't cut off the flow until the room
> temperature reaches about 27 degC. As others have said, if that isn't
> hot enough, remove the head and just leave the valve fully open.
>
> What is the orientation of the head? If it's vertical, and if you
> think it's being heated unduly by the rad itself, you could try
> fitting it the other way round, so that it is horizontal.
A further thought . .
If you really want to offset the temperature control range upwards, you
could try grinding a bit off the end of the pin - but that would, of course,
be non-reversible - and you'd have to make sure that you didn't grind so
much off that the valve didn't shut completely when the decorating cap was
fitted.
slider
"Roger Mills" <watt....@googlemail.com> wrote in message
news:7nsfcfF...@mid.individual.net...
Way too extreme. Just take the head off the valve like I said earlier.
RobertL
> "Roger Mills" <watt.ty...@googlemail.com> wrote in message
>
> news:7nsfcfF...@mid.individual.net...
>
>
>
>
>
> > In an earlier contribution to this discussion,
>
> >> In an earlier contribution to this discussion,
>
> >>> But it's not that the boiler shuts off prematurely. It's that the
> >>> cold room rad TRV turns off the flow at too low a temperature.
>
> >>> thanks for the discussion anyway folks.
>
> >>> Robert
>
> >> On its Max setting, it shouldn't cut off the flow until the room
> >> temperature reaches about 27 degC. As others have said, if that isn't
> >> hot enough, remove the head and just leave the valve fully open.
>
> >> What is the orientation of the head? If it's vertical, and if you
> >> think it's being heated unduly by the rad itself, you could try
> >> fitting it the other way round, so that it is horizontal.
>
> > A further thought . .
>
> > If you really want to offset the temperature control range upwards, you
> > could try grinding a bit off the end of the pin - but that would, of
> > course, be non-reversible - and you'd have to make sure that you didn't
> > grind so much off that the valve didn't shut completely when the
> > decorating cap was fitted.
> > --
> > Cheers,
> > Roger
> > ______
> > Email address maintained for newsgroup use only, and not regularly
> > monitored.. Messages sent to it may not be read for several weeks.
> > PLEASE REPLY TO NEWSGROUP!
>
I did think of grinding the pin, currebtly I am running with the heads
removed. i think that if I shove a rubber washer in there I should
be able t orais eth TRV by a few mm and that shoul do the trick.
They are mounted upright and are at the top, so they are in the worst
situation for getting an 'over optiomistic' feel for the room
tempertaure.
R
ARWadsworth
"Roger Mills" <watt....@googlemail.com> wrote in message
news:7nsfcfF...@mid.individual.net...
> In an earlier contribution to this discussion,
> Roger Mills <watt....@googlemail.com> wrote:
>
>> In an earlier contribution to this discussion,
>> RobertL <rober...@yahoo.com> wrote:
>>
>>>
>>> But it's not that the boiler shuts off prematurely. It's that the
>>> cold room rad TRV turns off the flow at too low a temperature.
>>>
>>> thanks for the discussion anyway folks.
>>>
>>>
>>> Robert
>>
>> On its Max setting, it shouldn't cut off the flow until the room
>> temperature reaches about 27 degC. As others have said, if that isn't
>> hot enough, remove the head and just leave the valve fully open.
>>
>> What is the orientation of the head? If it's vertical, and if you
>> think it's being heated unduly by the rad itself, you could try
>> fitting it the other way round, so that it is horizontal.
>
>
> A further thought . .
>
> If you really want to offset the temperature control range upwards, you
> could try grinding a bit off the end of the pin - but that would, of
> course, be non-reversible - and you'd have to make sure that you didn't
> grind so much off that the valve didn't shut completely when the
> decorating cap was fitted.
> --
> Cheers,
> Roger
> ______
You just want an excuse to use an angle grider as the solution:-)
Adam
frank...@gmail.com
I had to 2 x TRV4 chrome radiator valves fitted to 2 new radiators 6 month ago in summer. I have notice now in winter the radiator is not keeping room warm enough as it is shutting radiator off when set on max. I would say rooms were about 20-22 'C degrees.
If I remove the TRV4 head the radiator heats up to a roasting temperature. If screw the TRV4 to a lower setting the room gets colder. It seems proportional on both radiators. Its just MAX setting seem to low on both valves, any advice would be helpfull.
Drayton say this is nothing to do with radiator balancing and sounds like TRV head has problem. I am swapping out tomorrow the head from screw fix. I am not confident as it is both radiators doing the same and the are 6 months old.
Regards
Frank
newshound
are total crap.
I agree it sounds like a head problem. Have you tried unscrewing the
head attachment slightly, which will have effect of giving you a bit
more pin movement. If it works, you could use thread lock to fit the
head in the better position.
harry
They are more influenced by the nearby hot radiator than the room temperature.
You need to get heads for the TRV with remote sensors.
(They are connected by means of a capillary tube.)
http://www.plumbcenter.co.uk/product/drayton-trv-4-remote-sensor-capillary-2-m/
Put the sensor as far as possible from the radiator and NOT above it.
Andrew Gabriel
> TRVs are fairly useless objects.
> They are more influenced by the nearby hot radiator than the room temperature.
work extremely well. They are normally fitted in a position which
is the in-draft to the radiator from the room when the radiator
is on, so they follow room temperature very accurately when radiator
is on. Response is a bit more delayed when radiator is cut off,
because they've lost the draft past them.
> You need to get heads for the TRV with remote sensors.
> (They are connected by means of a capillary tube.)
>
> http://www.plumbcenter.co.uk/product/drayton-trv-4-remote-sensor-capillary-2-m/
>
> Put the sensor as far as possible from the radiator and NOT above it.
interesting challenge - something I've done a lot of experimenting
with over last 20 years. Attaching it to a wall with substantial
thermal mass does introduce some interesting errors which you won't
get by having it on the lower radiator tails. So does attaching it
to an external wall, which is where radiators are normally fitted.
--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
DerbyBorn
newshound
> In article <72c171d4-fa6b-4b66...@googlegroups.com>,
> harry <harry...@btinternet.com> writes:
>> TRVs are fairly useless objects.
>> They are more influenced by the nearby hot radiator than the room temperature.
>
> That was my thought, until I used them and found they actually
> work extremely well. They are normally fitted in a position which
> is the in-draft to the radiator from the room when the radiator
> is on, so they follow room temperature very accurately when radiator
> is on. Response is a bit more delayed when radiator is cut off,
> because they've lost the draft past them.
>
extra thermostats, but probably only to give "overall" rather than local
control.
I already have a switch by the back door in what would be the room
thermostat circuit (if I had one) so that it is easy to switch off the
CH if going out for part of the day.
frank...@gmail.com
OK, I swapped the Heads at screwfix, as they were still under warranty, and the problem is the same.
I think it is the raw heat of the pipes, The TRV body is red hot nearly. I think because it is chrome the heat is transfering and shuting down the TRV. I have swapped the head to return side as valve parts are the same and I can get 23'C in the room now, instead of 22'C the return side is cooler slightly as radiator heat is disipated.
Does anyone know if the white TRV4 units are plastic bodies or metal prayed white, wondering if these will not transfer heat to the head as much.
I do not think this to be normal as I have eden and bulldog valves(all plastic) on rest of radiators in house and on max setting my rooms will get far to hot so and I can bring them down to optimum setting, usually 3-4(on a 1-5 valve), this is the control I desire, and as per drayton specs, should get.
Yeah I know I should of bought what I knew worked but these two valve on two modern radiators so wanted something fancy. Might swap out in summer on a nice DIY day.
I think this must be normal for TRV4s I cannot not have 4 units that are dodgy.
As for raising valve a bit, I have purchased 1.6mm Nylon washers to fit inside the m30 thread. My only issue here is that I not sure if that valve will close as TRV head might not have enough stroke to close the valve. I am hoping that nylon will bite in the metal serated grip teeth that stop TRV head spinning. They should arrive tomorrow so will let you know.
Any comments, appreciated
Frank
frank...@gmail.com
Also looking at the Plastic RT212 and RT414, hopefully heat transfer will be less, will these fit on the body of a TRV4 valve, any idea.
Regards
Frank
frank...@gmail.com
Andy Burns
> I swapped the Heads at screwfix, as they were still under warranty,
> and the problem is the same.
that you can't gently pull it any higher with a pair of pliers.
> The TRV body is red hot nearly. I think because it is chrome the
> heat is transfering and shuting down the TRV.
> I have swapped the head to return side
How far open/closed are the lockshield valves?
newshound
excellent reputation. Do you know what temperature the CH circuit is
running at? I can see the logic of your "conductivity" argument, but I'd
be surprised if the design actually permitted it. Can you make up some
sort of shield from cardboard or expanded polystyrene which fits over
the sensor head but decouples the valve from any airflow around the
radiator, so that it definitely senses room temperature? (I once had to
re-arrange furniture around a TRV slighlty because it trapped the unit
in a "pool" of hot air from the radiator).
frank...@gmail.com
OK flow and return valves are the same, they are bi direction, arrows in both directions, so does not matter if TRV head is on either, they work the same, all be it they will have more heat exposure on flow side. I believe radiator balancing has nothing to do with this issue, as my radiator has flow. I have tried limiting flow but does not do anything different apart from slower to heat up but same effect of valve shutting down early. Drayton confirmed this.
flow and return pins seem good, all 4 identical in movement.
I realise manufacturers must take raw heat into the design. But Red hot valve heads cannot be good, my plastic bulldogs do not do this.
I think Drayton have gone for A efficiency rating in being keeping room at just warm temperature as max, not the cosy temp you want when your not well or its a freezing day.
Both valves TRV heads have plenty breathing space for air circulation.
My packing washers 27mm OD/20mmID 1.6mm wide have arrived.
http://www.ebay.co.uk/itm/M20-Nylon-Washers-Choose-from-6-different-sizes-10-per-pack-/132055449142?var=431413201473&hash=item1ebf1e3e36:m:mZNprj-x2kidWSSvdX_APeQ
I have fitted them and this has raised the head by about 2mm(1.6mm + depth of serated gripping teeth for anti head rotation). This has basically raised my max temperature setting of the TRV head. The TRV head now operates like the rest in my house, It is now usable how we want. 2mm is about 2 numbers on the valve positions if you look at the movement of shaft inside when you turn the head.
Tried last night on max and had to back valve off 2 division below as it was going to hot, it did shut the valve off, but just to hot, I was up to about 25'C. So now I have TRV that in my opinion should be standard setup.
Also due to the Nylon washer there is not as much heat transfer as there is not as much metal on metal valve to head body contact, just the threaded part.
I think I am happy with solution for now. Going to ring drayton and ask about compatibility of RT212 and RT414 heads on my valves, as they are plastic.
I think the way this valve is, I cannot believe people do not find same issue. I do not feel the cold, but I could tell this was not normal.
My solution is the best mickey mouse solution I could find, which would keep the head solid on the valve and work how it should.
Cheers for your time
Frank
harry
That's why some TRVs are horizontal rather than vertical.
To get the head further from the radiator and shielded from the radiant heat.
The hottest point on the radiator as where the valve is.
Also there is the issue of heat conducted from the valve body to the sensor.
Remote sensor cures all this.
Why do you suppose they make them?
The conventional/normal ones are cheaper but don't work well.
As you are finding out.
Especially in larger rooms.
Especially with one radiator in a large room.
frank...@gmail.com
RT212 Plastic Wax sensor head will fit on my valve
RT414 Plastic liquid sensor will fit on my valve
They kindly sent me two new chrome which I thought would do nothing different and a RT414 to try out. They said there should be no different.
I have tried the chrome TRV4 valves and they are exactly the same, heat transfering up the chrome and closing valve to early.
The RT414 tried on both radiators works perfectly. So I would all I can think is this is a design flaw in the plastic TRV4 being coated in chrome from head to valve seat the heat is transfered up the outside of the chrome and over heating the head.
The RT414 has plastic seat between head and valve so limited heat transfer and has ventilation slots.
Very strange.