Heat Pumps - post here.

angeldaisy

Can I ask, as the system we have in is around 17 years old, do you think the piping outside for the underfloor heating would be in good enough condition to get another ground source in?

Or is there a chance that we could start having issues with that?

The other question I have is that I have seen some companies in the UK and Europe offering a wood burning stove / boiler combination to power the underfloor heating. Does anyone have any experience with this?

ecowise

angeldaisy wrote: »

Can I ask, as the system we have in is around 17 years old, do you think the piping outside for the underfloor heating would be in good enough condition to get another ground source in?

Or is there a chance that we could start having issues with that?

The other question I have is that I have seen some companies in the UK and Europe offering a wood burning stove / boiler combination to power the underfloor heating. Does anyone have any experience with this?

There is really very little to go wrong with the collector part of the system except for the circulation pump. The only outside connections should be at the manifolds and if you have not been losing significant pressure it means leaks are not a problem. There would be a case for replacing the antifreeze in the collector but depending on your actual setup it may not be necessary. Our installation is 18 years old and the circulation pump was been replaced after it failed a few years ago. We also replaced the heating circuit pump recently with a 40W unit replacing a 245W unit and doing the same job.


I don't have experience of changing over to a stove/boiler heat source but the first thing that jumps out as a possible issue is temperature as the latter would work at much higher temperatures unless regulated.

angeldaisy

Okay, thanks for that, There are so many options to consider, its very confusing some times.

caveat emptor

Hi,

We've recently purchased a new build that comes with a samsung air to water heat pump. It looks like a 9kw size but can't be sure from the photos. I'm a bit concerned that it is a bit small for the size of the house (~150m2). The house has an A3 rating but I think the builder added in very low tech hole in the wall vents which may completely defeat the purpose of the energy efficiency. I know if it were air to air that would be know where near enough but I'm unfamiliar with the specifics of air to water. Should I be concerned with this or am I over thinking it? I'm going to get a survey done but unsure if they'd be able to cover the specifics of the heating requirements as regards the legislation. Any help appreciated.

Thanks,
Dan

ecowise

caveat emptor wrote: »

Hi,

We've recently purchased a new build that comes with a samsung air to water heat pump. It looks like a 9kw size but can't be sure from the photos. I'm a bit concerned that it is a bit small for the size of the house (~150m2). The house has an A3 rating but I think the builder added in very low tech hole in the wall vents which may completely defeat the purpose of the energy efficiency. I know if it were air to air that would be know where near enough but I'm unfamiliar with the specifics of air to water. Should I be concerned with this or am I over thinking it? I'm going to get a survey done but unsure if they'd be able to cover the specifics of the heating requirements as regards the legislation. Any help appreciated.

Thanks,
Dan

Have you looked into fitting more efficient vents? They are available in different forms from passive designs to active single room through-wall HRV units from companies like Venta-Axia. The old hole-in-the-wall approach is outdated.

KCross

caveat emptor wrote: »

Hi,

We've recently purchased a new build that comes with a samsung air to water heat pump. It looks like a 9kw size but can't be sure from the photos. I'm a bit concerned that it is a bit small for the size of the house (~150m2). The house has an A3 rating but I think the builder added in very low tech hole in the wall vents which may completely defeat the purpose of the energy efficiency. I know if it were air to air that would be know where near enough but I'm unfamiliar with the specifics of air to water. Should I be concerned with this or am I over thinking it? I'm going to get a survey done but unsure if they'd be able to cover the specifics of the heating requirements as regards the legislation. Any help appreciated.

Thanks,
Dan

If the house is well insulated etc the 9kW should be plenty but I'd worry about the open dumb vents. Those days are long gone.

Its going to be near impossible to tell how the whole house heating will behave until you live in it. If he scrimped on vents did he scrimp on insulation and I doubt much attention was paid to air tightness if he has open vents in each room.

I'd start with looking at getting those upgraded to something smarter that can open/close automatically or that is piped back to a heat recovery system... but that would be alot of extra money and somewhat difficult to retrofit.

Mickeroo

Something like lunos ald vents could be an improvement on the basic hole in the wall, though you'd need mechanical extractors put in too for them to work right.

caveat emptor

Thanks very much ecowise, KCross and Mickeroo for your replies.

We haven't actually moved in yet or exchanged contracts so it could be something to raise in the snag list. I was just worried when I saw heat pump and hole in the wall vents. There is a different forum here where people have moved in already so reaching out to them to see how they are getting on. The house is supposed to have an A3 rating but I read that the vents were added after. I've read similar stories of new builds having the heat pumps but not the correct airflow systems and large heating bills resulting.

Water John

Hard call. I would prefer to have mechanical heat recovery ventilation in any modern house. I suppose that's like now saying, if I was travelling to Dublin I wouldn't start from here.
Cost is about €5K. Retrofit, grief.
Are they simply bypassing different regs by making the vents after air turnover tests? That's totally unacceptable.

antoinolachtnai

Water John wrote: »

Hard call. I would prefer to have mechanical heat recovery ventilation in any modern house. I suppose that's like now saying, if I was travelling to Dublin I wouldn't start from here.
Cost is about €5K. Retrofit, grief.
Are they simply bypassing different regs by making the vents after air turnover tests? That's totally unacceptable.

Would it make sense for the poster to do his own air tightness test prior to closing if concerned about whether the building meets the current standards?

ecowise

antoinolachtnai wrote: »

Would it make sense for the poster to do his own air tightness test prior to closing if concerned about whether the building meets the current standards?

It would be good to know what the level of air tightness actually is but it would still be advisable to replace the holes in the wall with more energy efficient vents whether the regs are met or not.

Water John

If the vents were added and are not factored into the BER, it may be wrong. The house could be a B1 or 2. The house may not be, as advertised.

ecowise

Water John wrote: »

If the vents were added and are not factored into the BER, it may be wrong. The house could be a B1 or 2. The house may not be, as advertised.

Don't they mask off wall vents when they measure air tightness? They used to but perhaps things have changed. The idea was that they were just measuring fabric leakage and the wall vents were not classed as leakage. I always thought it was a daft practise.

Calahonda52

ecowise wrote: »

Don't they mask off wall vents when they measure air tightness? They used to but perhaps things have changed. The idea was that they were just measuring fabric leakage and the wall vents were not classed as leakage. I always thought it was a daft practise.

The airtightness is about uncontrolled, or unplanned air leakage, infiltration and exfiltration.
So vents are blocked as you say.

caveat emptor

Yeah I'd sounds mad that uncloseable vents are not included in ber assessment given that BER is used to measure typical heating bills on the website. i.e a BER Rated A3 house of 150 m2 should cost between €560 and €1100 but only if you never open your vents which you need to to prevent mould. Doesn't have the same ring to it I suppose. I find it hard to believe that builders can advertise houses at different ratings knowing that it can never be achieved as test conditions don't match operational conditions. Sounds like a similar German scandal where emissions of a different kind were involved.

I think I'll investigate further. Thanks for the replies. Really helpful. There were no fancy vents as far as I could see but I'll definitely be checking and post back.

Shefwedfan

So I am back around looking at heat pump again.....

I want to do a bit of investigation before the big speed. What is the best method to check a house? air tighness or one of those infrared heat loss surveys?

Also how much is air tightness do people know?

Calahonda52

Shefwedfan wrote: »

So I am back around looking at heat pump again.....

I want to do a bit of investigation before the big speed. What is the best method to check a house? air tighness or one of those infrared heat loss surveys?

Also how much is air tightness do people know?

.
Whats the project here: new/retro/refurb/?
.
ATT and IRI are complementary.
ATT numbers are easy to interpret from a a simple enough test.
An IR camera in the hands of a chancer.... well..

Shefwedfan

Calahonda52 wrote: »

.
Whats the project here: new/retro/refurb/?
.
ATT and IRI are complementary.
ATT numbers are easy to interpret from a a simple enough test.
An IR camera in the hands of a chancer.... well..

I posted on this thread last year, 3000sqft bungalow, have done a large amount of work internally but looking at a A2W heat pump to decrease oil dependency.....I have some prices for install and just going to fit in alongside boiler which will stay to top up if required but just wondering what investigation work I should do prior?

Calahonda52

A2W with rads will not be as cost effective as A2W with UFH because you will not get much use of night rate.
Have you MVHR?
what do u mean by what investigation work I should do prior?

Shefwedfan

Calahonda52 wrote: »

A2W with rads will not be as cost effective as A2W with UFH because you will not get much use of night rate.
Have you MVHR?

No heat recovery......

ecowise

Shefwedfan wrote: »

So I am back around looking at heat pump again.....

I want to do a bit of investigation before the big speed. What is the best method to check a house? air tighness or one of those infrared heat loss surveys?

Also how much is air tightness do people know?

First, re air tightness, have you read the preceding discussion regarding air vents? If you have hole in the wall vents they need to be addressed. Also does the house have fireplaces? These are huge loss points. Air tightness tests are useless if you have these 'designed' losses.

In terms of everything else my suggestion is to start with a manual pen and paper (or spreadsheet) list of all the ways your house is losing heat and their thermal characteristics (effective u-value) e.g

walls, roof, floor and their effective u-values
windows (including frame) and doors ditto
percentage contribution of each.

Also it usually makes sense to break a house into thermal zones and this could allow you to narrow your focus if it is appropriate.

If you want top see where thermal bridging is occurring in practise you can get a thermal imaging camera attachment for mobile phones. You can also investigate air leakages with a smoke pen (a stick of incense is not a bad substitute).

Calahonda52

The attached might help with the u value cals

68508224

Is it possible to heat a small swimming pool in a garage using the same heat pump as the house? Would it be a big job to set up?

al2009

68508224 wrote: »

Is it possible to heat a small swimming pool in a garage using the same heat pump as the house? Would it be a big job to set up?

Depends on size of pool, but this is common in spain etc, invest in a decent pool cover and you may need a seperate unit if you want pool warm all the time.

Water John

One would think the heating requirement of that amount of water would be very high compared to the air in a house. Someone here with the skills might do a calorific analysis.

Shefwedfan

Calahonda52 wrote: »

The attached might help with the u value cals

Thanks, any idea how to work out what type of radiators are already installed?

sydthebeat

Shefwedfan wrote: »

Thanks, any idea how to work out what type of radiators are already installed?

You should consider the grant hybrid system, which has a heat pump to get to decent temps, and an integrated oil boiler to get the higher temps.

Photo the rads you have...

H.E. Pennypacker

Can you find out the heat loss indicator from your BER assessor?

As an easy test re the workability of a heat pump, get a pipe thermostat on your flow from the central heating. Turn it right down to 40C and see what the house feels like on a frosty night. Note that its not good for your boiler to have a return temp of less than 40C over longer periods.

The SEAI grant might fund new radiators and a tiny bit of the heat pump if your HLI is ballpark (up to 2.3 as long as most works have been done and the rest are uneconomic). Interestingly (?), you can get the grant for a heat pump and retain your existing boiler as long as the heat pump and rads are specced to meet the heat requirements for the house.

Cyrus

ecowise wrote: »

It would be good to know what the level of air tightness actually is but it would still be advisable to replace the holes in the wall with more energy efficient vents whether the regs are met or not.

what vents would you suggest for more energy efficiency?

i am in a similar position to the poster albeit we have been in the house over 2 years,

its 195 sqm and A3 but to be fair electricity is running at 100 a month for a family of 4 so i cant complain (samsung heatpump)

Shefwedfan

sydthebeat wrote: »

You should consider the grant hybrid system, which has a heat pump to get to decent temps, and an integrated oil boiler to get the higher temps.

Photo the rads you have...

The likes of Dalkin and other can sit alongside the current boiler I have installed. So not a full rip and replace