HRV - Heat Recovery Ventilation - Anyone have it ?
Mung
some one mentioned that a HRV unit would help. Has anyone installed one or
knows some who has ?
Cheeers I'd be keen to hear from you.
Cheers
Piotr
robj...@gmail.com
we installed one of these about 18 months ago. Ours takes the warm air
from the loft space and pumps it into the house - it has a small
heater for when the loft air is below a set temperature. This has made
quite a difference to the overall comfort of the house - we do not use
our hallway storage heater any more, and the air is definitely drier,
and this was after one or two days. The overall running costs are very
reasonable; I would estimate perhaps $20 most of the time, but when
the heater kicks in it would go up to $40-50 per month, and we live in
Dunedin.
There is a HEPA filter on the unit as well, which I imagine will help
with allergies and asthma.
Any other questions?
Rob
Mung
<robj...@gmail.com> wrote in message
news:f978d466-cf1c-4f04...@s19g2000prg.googlegroups.com...
Thanks Rob, your email confirms what work colleagues are saying. I think I
need to suss it out.
Thanks for taking the time to reply.
Cheers
Piotr
Fred
"Mung" <Prince...@hotmail.co.nz> wrote in message
news:fqok3l$2l5$1...@lust.ihug.co.nz...
It appears they are quite useful at dragging roof cavity heat to inside the
house, and help reasonably well with condensation. The inbuilt heaing unit
that some brands offer on their top models is not so simple. There was quite
an item on fair go a while back about the inefficiency (read cost) of
running the heating elements. Huge amounts over the stated cost in their
promotional material, hundreds per month in one case. If I were going to get
one I would go for the basic unit which is a bit cheaper, than pay for the
inbuilt heater. A $25 dollar fan heater from the warehouse will almost
certainly do a better job of heating, so save the cost of that and put it
towards a heat pump. Then you've probably got the best set-up available.
Geopelia
"Fred" <gen...@zaradise.net.uk> wrote in message
news:47d04042$1...@clear.net.nz...
>
> "Mung" <Prince...@hotmail.co.nz> wrote in message
> news:fqok3l$2l5$1...@lust.ihug.co.nz...
>>
>> <robj...@gmail.com> wrote in message
>> news:f978d466-cf1c-4f04...@s19g2000prg.googlegroups.com...
>>> Hi,
(snip)
> It appears they are quite useful at dragging roof cavity heat to inside
> the house, and help reasonably well with condensation. The inbuilt heaing
> unit that some brands offer on their top models is not so simple. There
> was quite an item on fair go a while back about the inefficiency (read
> cost) of running the heating elements. Huge amounts over the stated cost
> in their promotional material, hundreds per month in one case. If I were
> going to get one I would go for the basic unit which is a bit cheaper,
> than pay for the inbuilt heater. A $25 dollar fan heater from the
> warehouse will almost certainly do a better job of heating, so save the
> cost of that and put it towards a heat pump. Then you've probably got the
> best set-up available.
>
Fair Go was looking at a dodgy installer, not the system itself. Just be
careful who you get to install it.
Fred
"Geopelia" <phil...@xtra.co.nz> wrote in message
news:fqpjbi$mkl$1...@aioe.org...
wattage of the heater unit and work out cost per kilowatt hour from your
supplier. It's horrifying. And think about a normal heater. Would you put it
just below the ceiling?
misanthropic_curmudgeon
> we are looking installing a HRV unit ?
The Midget and I put one into our place[1] here in Auckland about 18
months ago. The upshot was a slashing of the power bill as we hardly
run any additional heating and we dont need the dehumidifer to fight
the condenstaion - which was shocking. The subject of condenation is
an interesting one: we dont have any, any more.
As for allergens and the like, I cant comment: neither The Midget, The
Spawn or myself are asmatic or have ever had any problems like that.
Perhaps one of the biggest differences is that the house feels dry and
warm all year around.
I also put one into a rental I have which had a young couple expecting
their fisrt baby. Their comments are the same as mine.
I think the technology is great, and simple, and if you were so
inclined you could do it yourself for a fraction of the price (and
hope you got the air flow calculations right). - Or you could simply
stump-the-cash and have it done for you.
[1] A 1950's-era weatherboard house in Auckland.
Roger Dewhurst
If you replace three of four square metres of north facing roof with
glass or, better still, twin layer clear polycarbonate, with a sheet of
matt black steel just below it, you will get much more heat into the
roof space.
R
>
>
Dave N
The house needs to be able to 'breathe' for an HRV system to work otherwise
moisture will be driven into walls and carpets etc. (some modern houses have
had HRV systems removed!). The system is fine in 'non-airtight' houses
though if you can insulate the outer walls as well (admittedly not cheap!)
then you are well on the way to having an energy efficient and pleasant
enviroment. I agree with some other replies that a heatpump is far more
econmic for heating though the smaller units you commonly see are more
suited for only one room like the lounge.
Dave
<robj...@gmail.com> wrote in message
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Fred
"Roger Dewhurst" <dewh...@wave.co.nz> wrote in message
news:fqplos$m5c$1...@lust.ihug.co.nz...
> Fred wrote:
>> "Mung" <Prince...@hotmail.co.nz> wrote in message
>> news:fqok3l$2l5$1...@lust.ihug.co.nz...
>>> <robj...@gmail.com> wrote in message
>>> news:f978d466-cf1c-4f04...@s19g2000prg.googlegroups.com...
>>
>> It appears they are quite useful at dragging roof cavity heat to inside
>> the house, and help reasonably well with condensation. The inbuilt heaing
>> unit that some brands offer on their top models is not so simple. There
>> was quite an item on fair go a while back about the inefficiency (read
>> cost) of running the heating elements. Huge amounts over the stated cost
>> in their promotional material, hundreds per month in one case. If I were
>> going to get one I would go for the basic unit which is a bit cheaper,
>> than pay for the inbuilt heater. A $25 dollar fan heater from the
>> warehouse will almost certainly do a better job of heating, so save the
>> cost of that and put it towards a heat pump. Then you've probably got the
>> best set-up available.
>
> If you replace three of four square metres of north facing roof with glass
> or, better still, twin layer clear polycarbonate, with a sheet of matt
> black steel just below it, you will get much more heat into the roof
> space.
>
> R
Yes but the problem is not getting heat into the roof cavity, but getting in
through a layer of insulfluf or batts and into the house. Certainly an HRV
or DVS or any other brand will work better under a polycarbonate or dark
roof .
Fred
"Dave N" <dnelso...@paradise.net.nz> wrote in message
news:47d062c8$1...@clear.net.nz...
so it is only necessary because of the unit. Are you saving on your previous
accounts using the storage heater over the year? I'm also in Dunedin and I
used to run a Stack log burner with electric heaters occasionally. Fitted
two heat pumps which cost far less to run than buying firewood, and
drastically reduced my electricity bill as well. I do wonder if a DVS would
be sensible? In other words, would it reduce the heat pump running very
much? I'd be interested if anyone has used a ventilation system in
conjunction with a heat pump.
Roger Dewhurst
R
A _ L _ P
At one stage after repeatedly cleaning up a favourite cat-pee site on
the carpet (eventually had to cut out carpet & underlay) I had a fan
heater going night and day on it, set on fan not heat. This occurred
during winter. Despite the failure to cure the cat-pee issue I noticed
that the air was warmer and drier just from the constant movement.
Likewise with a ceiling fan in the lounge, whether set to force warmth
down in the winter or to rotate in the other direction in the warm
weather its most constant effect is of removing any stale damp chill in
the air and keeping the room more comfortable even when cold.
Naturally, bringing warm air from the ceiling or above is even better,
but as a cheap option using a fan to move air around seems strangely
effective at improving comfort. Here in Dunedin a house can easily get
that deadly chill in its "bones" that makes it miserable to come home
to, especially in rooms that aren't used often and where it is not safe
to leave windows open a fraction.
A L P
SupergoofNZ
>
> It appears they are quite useful at dragging roof cavity heat to inside the
> house, and help reasonably well with condensation. The inbuilt heaing unit
> that some brands offer on their top models is not so simple. There was quite
> an item on fair go a while back about the inefficiency (read cost) of
> running the heating elements. Huge amounts over the stated cost in their
> promotional material, hundreds per month in one case. If I were going to get
> one I would go for the basic unit which is a bit cheaper, than pay for the
> inbuilt heater. A $25 dollar fan heater from the warehouse will almost
> certainly do a better job of heating, so save the cost of that and put it
> towards a heat pump. Then you've probably got the best set-up available.
The advantage with the DVS heater is you can set it to come on at a
certain time, for example 5am so some of the chill's gone from the house
by the time you get up in the morning.
However, we have a DVS and to be honest I wouldn't recommend it for
heating. It's barely noticeable in our 127sqFt house, though the higher
ceilings probably don't help. Mum has a smaller house - about 100ft I
think - with normal height ceilings and she says hers makes a big
difference.
The DVS has certainly worked brilliant to dry out the house though, as
it is always circulating the air and brings the warm air down from the
roof cavity (except when it's in summer mode, then it turns off if the
roof air is over about 19 degrees). We got ours about 5 1/2 years ago,
so hopefully the technology and efficiency has improved a bit since then
too.
Now that cost od heat pumps has come down, if I had to do it over I'd
probably go for a heat pump this time around - or perhaps both, one for
ventilation and one for heating / cooling.
cheers
Rachel
misanthropic_curmudgeon
[snip]
> Here in Dunedin a house can easily get
> that deadly chill in its "bones" that makes it miserable to come home
> to, especially in rooms that aren't used often and where it is not safe
> to leave windows open a fraction.
Indeed. I had a flat on Colombo St in Christchurch when I was a
undergraduate that was like that. It was a duplex (number 1031, iirc)
that was made from concrete-clad and was about 100 years old.
Apparently that are of town used to be swamp, and if it was true it
would come as no surprise. It was the darkest, dampest, coldest shit-
hole you could imagine, and my flatmate who I knew from doing our
NZCE's in Wellington had signed us up for the year so we were stuck
with it.
I'd climb out of bed, and straight into clothes to cycle to Uni, and I
might have warmed up by the time we got there. Eat at Uni, go to the
gym, ride home all smelly and hop straight into the shower as way of
getting some warmth going on. (Showering before a ride just makes your
head ache from cold wet hair).
We tried the two fireplaces, and they did have an effect, but we used
up our wood by May brough some more which took us through to June, and
then we were broke at it was miserable from then on. Living in that
place was the best incentive to get laid - and spend the night at
'her' place - that I have ever encountered.
I actually drove past it a while ago when I was back down there, and
it still stands, and still is a cold-looking shithole. I suspect that
place is so cold and wet you could not even burn the bugger down.
Kay Neich
"SupergoofNZ" <thunderbi...@penelope.net> wrote in message
news:47d0f9ab$1...@clear.net.nz...
> Fred wrote:
>
> However, we have a DVS and to be honest I wouldn't recommend it for
> heating. It's barely noticeable in our 127sqFt house, though the higher
> ceilings probably don't help. Mum has a smaller house - about 100ft I
> think - with normal height ceilings and she says hers makes a big
> difference.
Yeah, we put in a HRV with no heating element last mid-winter. Half our
place is sarking, and for just distributing the great heat we get from that
north facing part of the house better, I don't think the effects of the
sarking were calculated accordingly - there's just one grill on the wall
into that part of the house. We still needed a dehumidifier for the
remainder of winter, but it was an exceptionally cold one, so we'll see what
happens this year.