Heat Pumps - post here.

KCross

ecowise wrote: »

We have a Genie 9kW ground source heat pump installed in 2001. It has served us well over the 18 years but during the last heating season the compressor cut out on 5 occasions (usually soon after coming on) and I am wondering if it is time to look for a replacement heat pump or can it be serviced to be more reliable. It worked fine each time after being reset but it is a nuisance as it is timed to come on at night so it only gets discovered the following day. The compressor make is Copeland. Has anyone experience of these units or knowledge about compressor reliability/longevity?

It might not be the compressor. Could be something like the soft starter.

Get a service guy out and see what the root cause is first and if it is the compressor and everything else is Ok it should be fine to just fix it. Don’t see why you’d have to replace the whole heat pump if everything else is fine.

ecowise

Thanks for suggestions. Being in a very rural location it is a bit more difficult getting a service but there are some talented refrigeration people around who understand the basic components so I will try that route.

Stephen_89

Can heat pumps work in a house with suspended wood floors? Having EWI done, eindows, doors and attic insulation and thinking of heatpump. Would we need to fill floors for thermal mass or would rigid board between joists cut it?
House is detached dormer with c. 2400sqft area. 200m2 area downstairs.

Cheers!

KCross

I doubt it Stephen. The whole idea of underfloor heating is that there is a large concrete thermal mass there. Heating the timber directly as your heat store would have the heat pump cycling continuously.

ch750536

I have a standard 4 bed single story, burning oil at the moment and want to stop as it is bad for the environment. House built in 2004 with good insulation. Family of 4 who have a good understanding of being frugal (put on a jumper, showers only etc).

Is there a good approx price for this standard setup? At the moment it seems you need to get quotes from different companies, quite painful where I am in the back woods of the west coast. I don't want to call people in until I have enough savings.

Calahonda52

How good is the air tightness?
Is house site exposed to salt air?

ecowise

ch750536 wrote: »

I have a standard 4 bed single story, burning oil at the moment and want to stop as it is bad for the environment. House built in 2004 with good insulation. Family of 4 who have a good understanding of being frugal (put on a jumper, showers only etc).

Is there a good approx price for this standard setup? At the moment it seems you need to get quotes from different companies, quite painful where I am in the back woods of the west coast. I don't want to call people in until I have enough savings.

I think, as suggested by Callahonda52 regarding air tightness, it is best to first optimise house thermal characteristics. What was considered good insulation in 2004 was not very good. The same is true for glazing & doors. Having looked at what options you have to thermally improve the house then evaluate heating options.

Water John

Stephen, you can. On the ground floor you need insulation under, then and you put in spreader plates. These are a metal sheet moulded with two or three U's to take the UFH pipes and sit on the joices.
Yes as Cross says you don't have the mass, so this works as a direct heating system with a quick response. It would work best with a large heat storage cylinder and a secondary loop. This would reduce the on/off switching on the HP.

KCross

Water John wrote: »

Stephen, you can. On the ground floor you need insulation under, then and you put in spreader plates. These are a metal sheet moulded with two or three U's to take the UFH pipes and sit on the joices.
Yes as Cross says you don't have the mass, so this works as a direct heating system with a quick response. It would work best with a large heat storage cylinder and a secondary loop. This would reduce the on/off switching on the HP.

I'd say it would not be efficient, have reduced lifespan on the compressor and not give great heat.

A loop of pipes under the floor with no concrete to heat up is going to be a poor heat distribution system. Radiators would probably be better and they're not ideal either.

Do you know someone that has their system setup like you describe?
I'd be interested to know how much cycling the pump is doing.

ch750536

Calahonda52 wrote: »

How good is the air tightness?
Is house site exposed to salt air?

Pretty good, no.

mcbert

Calahonda52 wrote: »

How good is the air tightness?
Is house site exposed to salt air?

Is sea air really a problem? It is a small enough island, with a large % of our population living within a few miles of the sea, Im guessing. How close to the sea is 'bad' ? And what are all those people supposed to do if HPs arent suitable for sea air?

KCross

mcbert wrote: »

Is sea air really a problem? It is a small enough island, with a large % of our population living within a few miles of the sea, Im guessing. How close to the sea is 'bad' ? And what are all those people supposed to do if HPs arent suitable for sea air?

It only affects Air-To-Water heat pumps, not Ground Source heat pumps. The reason being that A2W heat pumps have a unit (with a coil) physically located outdoors and the salt air will corrode that over time... hard to quantify though... which is your point I guess.

A ground source heat pump has nothing outside other than pipes which are under the ground protected from all weather, even frost.


If someone who works in the trade is on here they might share their experience of servicing an A2W system that has been on the coastline for 5-10 years?

Calahonda52

mcbert wrote: »

Is sea air really a problem? It is a small enough island, with a large % of our population living within a few miles of the sea, Im guessing. How close to the sea is 'bad' ? And what are all those people supposed to do if HPs arent suitable for sea air?

Specifically designed models have stainless steel kit outside, with more accessibility to clean the salt off the evaporator.

KCross

Calahonda52 wrote: »

Specifically designed models have stainless steel kit outside, with more accessibility to clean the salt off the evaporator.

How bad does that become over say one winter.... is it something you do once a year or every few weeks?

Harry Palmr

Hi I'm wondering about an air to air pump for a three bed bungalow, the layout is typical suburban "long and narrow" with 6 rooms and a hallway, the east gable end has the back garden, I'd hope there was a system which could power at least three units - kitchen (back)/bathroom (side)/lounge(same side-front) - who can be recommended as a supplier and fitter for such a set up?

MENACE2010

you need to find an installer in your area, they can calculate what you need . The description is not detailed enough for an assesment online .. in this forum ( its impossible to asses the heating needs of your house )

angeldaisy

Could someone offer some advice please.
We built our house in 2002 and installed underfloor heating powered by a ground source heat pump.
Unfortunately there has been a leak in one of the heat exchangers, which has caused huge problems and both the refrigeration team and the heat pump company we use have informed us that as the unit is 17 years old it is not feasible to repair it.

So my options are;
Replace with another ground source heat pump
Replace with an Air to water heat pump
or install an oil boiler to heat the house.

My initial reaction is to discount the oil option, but I am torn between the two different types of pump. It is obviously an expensive outlay, so want to make the best decision and would like some impartial advice if at all possible.
Many thanks

KCross

Its in their best interest to sell you a new one.

Do you trust them that its not economic to repair? A leak doesnt sound like a terminal thing but maybe it is.

Maybe get a second opinion?

angeldaisy

As far as I know, I would need to replace the compressor (around 1k) plus the heat exchanger, along with various other components.
We haven't had much luck with it over the past few years and I've a feeling that this is just the final nail...

KCross

angeldaisy wrote: »

As far as I know, I would need to replace the compressor (around 1k) plus the heat exchanger, along with various other components.
We haven't had much luck with it over the past few years and I've a feeling that this is just the final nail...

Have you got quotes for another GSHP and an A2W to compare against?

What have your electricity bills been like? Is the house well insulated?

GSHP will be cheaper to run but more expensive to buy so its a tradeoff.

angeldaisy

KCross wrote: »

Have you got quotes for another GSHP and an A2W to compare against?

What have your electricity bills been like? Is the house well insulated?

GSHP will be cheaper to run but more expensive to buy so its a tradeoff.

I'm waiting for the quotes to come in, but they are advising that the air to water could be around 8k plus installation.

Electricity could be around 1500 - 2000 per year, but that is for all our electricity needs. No gas, oil etc...

Water John

Leccy is high but a 2002 build would not have a very high BER.
If replacing I would def go with GSHP again as you have the groundworks already in place. The electricity cost on an A2W would probably be a good bit more on your annual bill.

KCross

angeldaisy wrote: »

I'm waiting for the quotes to come in, but they are advising that the air to water could be around 8k plus installation.

Electricity could be around 1500 - 2000 per year, but that is for all our electricity needs. No gas, oil etc...

What make/model heat pump was it that died?

You cant really make a decision until you see both prices.

Water John wrote: »

The electricity cost on an A2W would probably be a good bit more on your annual bill.

+1

ecowise

angeldaisy wrote: »

I'm waiting for the quotes to come in, but they are advising that the air to water could be around 8k plus installation.

Electricity could be around 1500 - 2000 per year, but that is for all our electricity needs. No gas, oil etc...

Do you know how much of that bill is due to heating? We heat a 245 m2 house for about €250 a year using a GSHP (augmented by a wood stove using our own wood) but the house is well insulated and pretty air tight. If buying a new HP it might be worth importing one as there can be significant savings. An 8kW Dimplex imported from Germany is about 5K plus delivery (probably about 200 €) and what appear to be well made Chinese units are half that price (just like with solar the Chinese have invested hugely in heat pump technology). Check the German eBay listings.

Calahonda52

ecowise wrote: »

Do you know how much of that bill is due to heating? We heat a 245 m2 house for about €250 a year using a GSHP (augmented by a wood stove using our own wood) but the house is well insulated and pretty air tight. If buying a new HP it might be worth importing one as there can be significant savings. An 8kW Dimplex imported from Germany is about 5K plus delivery (probably about 200 €) and what appear to be well made Chinese units are half that price (just like with solar the Chinese have invested hugely in heat pump technology). Check the German eBay listings.

if a new house, who will sign off on such stuff for irish compliance?

ecowise

Calahonda52 wrote: »

if a new house, who will sign off on such stuff for irish compliance?

My understanding is the the equipment just needs to have a CE certificate, after that it is up to the installer. Perhaps there is more to it than that?

Calahonda52

ecowise wrote: »

My understanding is the the equipment just needs to have a CE certificate, after that it is up to the installer. Perhaps there is more to it than that?

Then will the warranty be valid if not installed by an approved installer?

ecowise

Calahonda52 wrote: »

Then will the warranty be valid if not installed by an approved installer?

I think each individual has to make their own call on this question and each case is different. But, for example, if the cost difference between going an "official" route and an independent one is in the 000's (and it can be a lot) the question that needs to be asked is how much would you pay for a warranty? Is it 000's considering the general quality of modern manufacturing processes? However, it is an individual's call to make.

angeldaisy

ecowise wrote: »

Do you know how much of that bill is due to heating? We heat a 245 m2 house for about €250 a year using a GSHP (augmented by a wood stove using our own wood) but the house is well insulated and pretty air tight. If buying a new HP it might be worth importing one as there can be significant savings. An 8kW Dimplex imported from Germany is about 5K plus delivery (probably about 200 €) and what appear to be well made Chinese units are half that price (just like with solar the Chinese have invested hugely in heat pump technology). Check the German eBay listings.

I reckon the heating is quite heavy, as my bills with no heating are around 100 or so per 2 months.

I guess there are going to be a lot of decisions to be made!
I think for now we might even just end up installing a stove and using portable heaters for the bedrooms. Certainly can't face a huge bill this side of Christmas.

ecowise

angeldaisy wrote: »

I reckon the heating is quite heavy, as my bills with no heating are around 100 or so per 2 months.

I guess there are going to be a lot of decisions to be made!
I think for now we might even just end up installing a stove and using portable heaters for the bedrooms. Certainly can't face a huge bill this side of Christmas.

It might still be worth looking at a repair option. There are some companies that specialize in heat pumps (at least I know of one in west Cork!) who are quite able and willing to do repairs. I know it is time consuming but search around for someone similar in your own area and you might get a cheaper quote. Sometimes good used units also come on the market. It is a difficult time of the year to get a big bill so I hope something suitable turns up.