Heat Pumps - post here.

[Deleted User]

Thanks for the feedback. Looks like I would need a lake not a pond to make this work. I thought if the pond would only need to be 20%-30% bigger it could work but appears I’d need a huge body of water.

Calahonda52

MAXFANTANA wrote: »

Thanks for the feedback. Looks like I would need a lake not a pond to make this work. I thought if the pond would only need to be 20%-30% bigger it could work but appears I’d need a huge body of water.

How much land have you got for a horizontal looped system?

the_amazing_raisin

MAXFANTANA wrote: »

Thanks for the feedback. Looks like I would need a lake not a pond to make this work. I thought if the pond would only need to be 20%-30% bigger it could work but appears I’d need a huge body of water.

Yeah I was looking at an underground setup for something back garden scale, but the depth the tank needed to be buried plus the size of tank I'd need made it pretty uneconomical

As others have said, if you have a lot of land and access to a digger then it's pretty worthwhile

the_amazing_raisin

Calahonda52 wrote: »

It must be there 15 years now and the water is pretty much primordial soup at this stage but works great. I think its a great idea as not heat dumping from the thermal panels and the high delta t between the soup and the panel, heat transfer is good

I love this description

I guess it hits upon another flaw in combining systems with different purposes, a natural swimming pond kind of implies the water should be heated naturally and not used as a heating source or thermal battery. Otherwise the "nature" in the pond might not be something you'd want to be swimming in

[Deleted User]

the_amazing_raisin wrote: »

I love this description

I guess it hits upon another flaw in combining systems with different purposes, a natural swimming pond kind of implies the water should be heated naturally and not used as a heating source or thermal battery. Otherwise the "nature" in the pond might not be something you'd want to be swimming in

Yeah exactly I was thinking something like in this video.

https://youtu.be/FPUZ4jrfNqM

Thought maybe with our climate and more modest house sizes I could have the natural swimming pond and then have the heating loop sit at the bottom with little affect on the pond (other than a small temperature drop). I will probably go ahead with the pond anyways and go for an air to water heat pump.

the_amazing_raisin

MAXFANTANA wrote: »

Yeah exactly I was thinking something like in this video.

https://youtu.be/FPUZ4jrfNqM

Thought maybe with our climate and more modest house sizes I could have the natural swimming pond and then have the heating loop sit at the bottom with little affect on the pond (other than a small temperature drop). I will probably go ahead with the pond anyways and go for an air to water heat pump.

Sounds like a better setup, I've had an ASHP for years and it's grand, cheaper than gas and the house is warm

I know a lot of folks swear by GSHPs but unless you've a big patch of open land with easy access then I think Air source is easier and more economical

If you go with the ASHP then I'd recommend finding one that has a good support network

I've a Dimplex and there's only 2 companies that service it that I could find. Not great when you need it fixed quick and they're busy

Perez2017

Do i turn my heat pump off in summer? As in main unit?

KCross

Perez2017 wrote: »

Do i turn my heat pump off in summer? As in main unit?

Generally not, it should turn itself off other than just powering the electronics and temp sensors.

JonMac

I've got a Samsung A2W heat pump and a Joule pre-plumbed cylinder which feeds my UFH.
My plumber told me to keep the water pressure at 1.5 bar.
Since the heating has stopped due to our wonderful weather, the pressure has dropped down to 0.5 bar.
Is this because the slab has cooled and the water volume has contracted?
Also, is there any reason I can't set the pressure higher? I found this in a user manual "there is no
pressure sensor in the unit so we can operate from open vented to 3 bar maximum."

JonMac

"Do i turn my heat pump off in summer? As in main unit?"

Don't you use it for DHW? Much cheaper than an immersion.

KCross

JonMac wrote: »

I've got a Samsung A2W heat pump and a Joule pre-plumbed cylinder which feeds my UFH.
My plumber told me to keep the water pressure at 1.5 bar.
Since the heating has stopped due to our wonderful weather, the pressure has dropped down to 0.5 bar.
Is this because the slab has cooled and the water volume has contracted?
Also, is there any reason I can't set the pressure higher? I found this in a user manual "there is no
pressure sensor in the unit so we can operate from open vented to 3 bar maximum."

Yes, normal for the pressure to fluctuate a bit. As long as it doesn’t go to zero you’re probably alright.

I wouldn’t go raising the pressure. Nothing to gain that I’m aware of and you’ll just stress all the joints more.

Calahonda52

KCross wrote: »

Yes, normal for the pressure to fluctuate a bit. As long as it doesn’t go to zero you’re probably alright.

I wouldn’t go raising the pressure. Nothing to gain that I’m aware of and you’ll just stress all the joints more.

Same as a wet rad closed system

the_amazing_raisin

Perez2017 wrote: »

Do i turn my heat pump off in summer? As in main unit?

Nope, it'll only come on when the thermostats say the house is too cold, so just make sure they aren't set too high

Also as JonMac said you'll presumably want hot water during summer. It's not quite warm enough here for cold showers

JonMac

Buyer's remorse: I changed from a gas boiler to a A2W heat pump a year ago; it is a HP plus cylinder package from a well known Irish company. It has had 5 problems so far. In 16 years I had 1 problem with the boiler and that was an external Honeywell actuator for the diverter valve.

Yes, the last 12 months electricity costs were 590 euro lower than the previous 5 years propane plus electricity, but the 250 euro charge for the annual service takes a good bite out of that.

I was quite irritated while on hold for the service department as I was listening to the company touting their wonderful new gas boiler with only 4 moving parts!

In retrospect, I would have been better off, financially and emotionally, to have just replaced the gas boiler. Just my 2 cents.

KCross

but the 250 euro charge for the annual service

That sounds like a bit of a shakedown to be honest. Does it really need a yearly service? What did they do for the €250?

ansible

I'm in the early stages of a new build design - one off house in a rural location. I'm still figuring out what renewable energy solutions the house will include but seems like it will include an air to water unit and likely an MHRV. I want to make sure I allow enough room at this stage for a suitable plant room. I appreciate it's tricky when I don't know what plant I want it to accomodate - does anyone have any ballpark suggestions I should be aiming for? (approx size 220 sq m, single story).

Also, is a plant room better located in the middle of the house, or adjacent to an external wall? Where I'm considering locating it would put it under a flat roof, is that a bad idea or would it be more effective located under a loft space?

Thanks

funnyname

Hi, we bought a house (built 2001) 7 years ago, it has a gshp, attached photo is the wiring diagram, name on it is Phoenix P400, can't find anything on it when I search the net.

Anyone ever hear of it?

Never had it serviced either, anyone able to recommend an engineer in the mid-west to have a look at it?

It's still working away fine for heating the underfloor downstairs but woeful at providing DWH at the same time. There was underfloor installed upstairs but I'm guessing it never worked due to it being a suspended timber floor and rads (oil fired boiler providing heat for these and DWH) being added afterwards.

Tombo2001

Hi folks

Am sure the answer is in here somewhere:

Do Heat Pumps make any sense whatsoever in a retro fit?

We had an architect in recently who told us we'd be mad not to do it.

10k to install, and then spend god knows how much in insulating the floors with poured concrete, replacing the suspended wooden floors that are there at present. At the moment we pay about 1000eur per annum for an oil boiler, which needs to be replaced.

I cant see any possible way that this would work financially.

Am I missing something?

Calahonda52

https://www.boards.ie/discussion/comment/117893990#Comment_117893990

Airtightness

Insulation

heating controls

heating system

concrete floor is over kill

will take months to dry out

research SR 54

sydthebeat

https://www.boards.ie/discussion/comment/117893990#Comment_117893990

theres a very easy answer to this, and im suprised your architect didnt suggest it.

SEAI give grants for heat pump installations in retrofits.

They have parameters which must be met in order to qualify because they do not want people putting Heat Pumps into unsuitable houses and then ending with huge electricity bills.

if you keep to, and meet, the SEAI parameters and processes, then your build should be suitable.

suspended wooden floor are going to be a big issue. regardless of whether you go with a heat pump or not, you should get this resolved anyway.

KCross

https://www.boards.ie/discussion/comment/117893990#Comment_117893990

It probably wont make financial sense unless you are planning to take the house back to walls anyway? Is the architect just overseeing an extension or are you doing major works?

Calahonda's post above is the order in which you should be doing things.... heat pump would be well down the list.

Tombo2001

https://www.boards.ie/discussion/comment/117895357#Comment_117895357

The issue isnt the grant on the Heat Pump or the cost of the heat pump, the issue is the cost of bringing internal suspended floors to a point where we can qualify for a Heat Pump grant.

sydthebeat

https://www.boards.ie/discussion/comment/117896153#Comment_117896153

without doing the necessary investigatory works ie prelim BER assessment, and synthesising different solutions... everything you consider at this stage is just shooting into the dark.

do you know exactly WHAT you need to do to "bring internal suspended floors to a point where we can qualify for a heat pump grant" ?

Tombo2001

https://www.boards.ie/discussion/comment/117896333#Comment_117896333

I dont being honest - I dont know the costings of underfloor insulation. But I imagine its substantial, 10k at a minimum.

And thats my point - that at the moment I pay circa 1000 per annum for oil. Acquiring a heat pump costs 20k, half for the pump and half for the underfloor upgrades, not even mentioning new windows or drylining. And the savings just dont warrant it. Shelling out 20k to save 500 eur per annum.....if I am shelling out 20k the savings would want to be four or five times that amount.

Looking at it differently - the whole thing about only qualifying for a Heat Pump when the house is fully insulated to the best modern standards. its a bit like the parable of the stone soup - if the house is really insulated to that level, you can probably heat it with a one bar plug in radiator that costs 200 euro in Argos. What is the need to shell out 10k for a heat pump. So you can turn it on and off with your phone? Dont care.

Obviously I might be completely off here - I am just stating how it appears to me, at present.

Tombo2001

https://www.boards.ie/discussion/comment/117896333#Comment_117896333

But point taken - starting point here is to do the relevant BER work. Thanks.

sydthebeat

https://www.boards.ie/discussion/comment/117898067#Comment_117898067

what are you basing those figures on? (and to fair, a lot of people would consider a 10 year return {20k at 500 back per annum} as being a decent return on investment)

have you had the assessment to figure out of you have to change windows? have you considered insulating and air tighting the floor without a concrete pour?

have you considered radiators instead of UFH? have you had your home assessed to see if rads are a viable fit? if so have you priced this up?

you are incorrect about a heat pump only being suited to the best modern standards. modern builds have to be on average A2 minimum. they have HLIs of just above 1.0

Heat pumps can work perfectly well in B rated or better homes, and home with HLIs of approx 2.0 (these arent stone soups!)

not being offensive here, but what you appear to be doing is flailing around in the dark finding reasons why a heat pump wouldnt work / be too expensive.

oh, and if you want a build that you can heat off a plug in rad, you have to put a serious amount of time, energy and money into planning and perfecting the build, im talking high level passive standards.

Modern irish building regulations are not high level passive standards.

sydthebeat

https://www.boards.ie/discussion/comment/117898086#Comment_117898086

you posted the above while i was compiling my previous post.

Sourcing a Technical Advisor is the starting point

The BER assessment comes after

vincenzolorenzo

https://www.boards.ie/discussion/comment/117898107#Comment_117898107

€20k investment for €500 saving is a 40 year payback. He has a point though, a modern A rated home has an extremely low heat requirements. Energy for domestic hot water actually exceeds it. From a purely financial point of view heat pumps are an expensive heating method for modern home. Storage heaters on night rate electricity would be far lower capital cost, for only marginally higher operating cost.

However what you can't put a value on is the comfort of the modern heating system/home. Your house is basically warmer for longer compared to an oil and rads setup. The comfort aspect, plus the poor reputation of storage heaters, are one of the prime drivers for retrofitting heat pumps into houses.

Tombo2001

https://www.boards.ie/discussion/comment/117898126#Comment_117898126

Cheers - they are fair points above. THanks.

sydthebeat

https://www.boards.ie/discussion/comment/117898299#Comment_117898299

yes it is!

ill blame the lack of coffee on that one this morning :)