Air Source Heat Pump

[Kayos]

@Kayos you are correct in stating fabric first... you need to know the total heat loss to match the minimum heat input. The type of building and its construction then becomes irrelevant, but the costs can be eye watering.

@Welderpaul i suspect your underlying issue is related to the above. Uk insulation and leakage standards are still a bit (lot) pants and still fall well short of passive/scandi insulation standards. If your system was specified for a passive house (which at 6kw seems very likely) but you don't meet or exceed that criteria then it's never going to work when it gets cold.

I also suspect the "standard information" for system capacity is based in an unrealistic ideal perfect universal building model with no basis in the real world. When "everybody" says its right but it doesn't work and the "experts " want lots of cash to make it work I find myself catching the strong smell of manure being thickly applied to cover over the cracks.

We don't use standard information, we do extensive surveys and build a digital twin of the building, this enables us to model and simulate all different options

The fact is that it's often cheaper to have slightly higher energy costs than spend the huge upfront costs on fabric upgrades

 

[Kayos]

im sorry to say a sealed house award means jack all and i see it so often

plastic bag over the hobs cover to create a seal for the test removed after as direct to the outside wall, weep vent windows temporary sealed, new toilets have direct to pan but the older type have an overflow pipe that also needs sealing

as goes for the buildings we lack the insulation on many new and certainly with old builds

as goes for your security of state comment well of coarse they will fit them we are all paying for them and so we also pay when they fail by fault or design or it wont work at that temp, hell it dosnt matter to them there not paying the bill or if it fails to work its all payed for by the tax payer.

im not going to go down the bore hole reference but normal air to heat source isnt going to cut it the tech isnt there even gas boilers dont make 100 percent effiecntency

Not getting political but "we" do not pay for anything, the scheduled ancient monument status applies to the history and archaeology of these buildings that are privately owned. The secretary of state bases their decision on Historic England's recommendation

And no, they do not get automatic approval, it is a costly and difficult process but shows that people want to improve and protect the building ls by pursuing decarbonisation l, even when it is challenging

 

[gaz1]

@Welderpaul apologies for being part of the derailment of your thread

In your case, the cost to rectify does not outweigh the benefits which is a shame as new builds should be prime for heat pumps

Also to anyone else reading, if you want facts on heat pumps in old buildings, with data to back it up. Please PM me or even risk starting a thread. My day job is to decarbonise buildings, with the caveat the net energy use goes down (we remove gas but use more electricity, however the overall must be lower) if it isn't, we don't get paid!

for the elctricity boilers they are there still way behind gas boilers wood boilers or even oil boilers

as goes for there repairs its still the same

expensive heat exchangers and awful electronics works fine to a degree but they are also a throw away boiler certainly wont last the test of time

with the electricity type you have to deal with wear and tear on the coils, coating on the elements and replacement of the coils

rough idea your coil within an emersion heater or like your 10kw shower x2-x3 just to get to the temps of the boiler to heat the central heating output

A 10 kW shower uses approximately one kWh of energy in six minutes a boiler needs 20 mins on each cycle

electricity to air well insulated house will show well with flash heat not prolonged heat rough reference to that heat is the old air boilers used in the 80s and also used in factories with there noisey blowers

 

[mike os]

Not getting political but "we" do not pay for anything, the scheduled ancient monument status applies to the history and archaeology of these buildings that are privately owned. The secretary of state bases their decision on Historic England's recommendation

And no, they do not get automatic approval, it is a costly and difficult process but shows that people want to improve and protect the building ls by pursuing decarbonisation l, even when it is challenging

Ive done a few jobs on scheduled monuments (and grade 1 listed) ... absolute pain in the happy sack from start to finish

Individual building modelling is the only way i can ever see it working for any non standard building...

 

[knighty]

@Kayos , can an air source be tied in with ground source as in the bore holes you were involved with? Just wondering if a combination of the two would be a viable solution.

Bob

you could... but there's not much point, ground source is so much more efficient and reliable than air source, especially with bore holes where (I had to google to double check my numbers here) - the bore hole water temperature is higher than air temperature most of the year here in the uk

 

[Onoff]

as goes for your security of state comment well of coarse they will fit them we are all paying for them and so we also pay when they fail by fault or design or it wont work at that temp, hell it dosnt matter to them there not paying the bill or if it fails to work its all payed for by the tax payer.

When it doesn't work they (read we) just pay an old mate, their BiL or whatever for another long winded consultation and install a supplementary heating system.

 

[gaz1]

@Welderpaul

you still have to get a wagon in to feed the tank

my advice is to go for oil with an oil boiler techs come along much further

now you state you want an underground tank its worth considering an underground room as a underground boiler house this gives you a few benefits as its insulated warm and canbe used a store room of heat from tanks

like @brewdexta wood stove room and hot water cylinders that can also be used for solar heating as well

plan it right and you will have a good system

 

[gaz1]

you could... but there's not much point, ground source is so much more efficient and reliable than air source, especially with bore holes where (I had to google to double check my numbers here) - the bore hole water temperature is higher than air temperature most of the year here in the uk

its why i didnt bring it up however if your boring then the surrounding propertys should share it and pay the owner and this should be factored into it

same with the sand heater that runs a small city

i dont like bore holes its bad enough with mine shafts how many holes do we need in the ground under us before we say enough

 

[Bornfree]

you could... but there's not much point, ground source is so much more efficient and reliable than air source, especially with bore holes where (I had to google to double check my numbers here) - the bore hole water temperature is higher than air temperature most of the year here in the uk

The water temperature from our irrigation bore is normally 11° summer and winter.

 

[knighty]

its why i didnt bring it up however if your boring then the surrounding propertys should share it and pay the owner and this should be factored into it

same with the sand heater that runs a small city

i dont like bore holes its bad enough with mine shafts how many holes do we need in the ground under us before we say enough

it's just a hole straight down.... not that wide either... not much to worry about

better than a trench with water/power/gas/whatever in

 

[Farside]

That looks lovely set against that sandstone wall...

If you can afford one of those, you live in a house with several walls where it won't be noticed, out of sight.

 

[Rannsachair]

Looked into a heap pump myself a couple years ago and working in other peoples houses occasionally come across people with them fitted and I always ask the owners what they think of them and I can honestly say i've not ran into anyone that absolutely loved it yet, same complaint over and over again that its pants in winter.

It's unfortunate that the only people i've heard rave about them either sell them or fit them. I'm sure there are some excellent working installations out there, in a perfect house, somewhere. It just seems that the bad far outweighs the good from what i've seen so far. So i'm staying clear!

I am really happy with my air source heating. Mitsubishi Ecodan installed 4 years ago in a 15 year old house. Similar experience to my neighbours.

We are in a remote area with no gas and almost all houses fitted with storage heaters. The airsource gives me a warmer house with better control at reduced cost. I was lucky I got an interest free loan for the installation through the Scottish Government and recoup most of the money in quarterly payments from Ofgem domestic RHI.

I have had no issues, it was a painless install: taking out the storage heaters, fitting radiators, pipes etc was done in one day then a half day to test and fit insulation on the pipes.

I think it depends on your circumstances, compared to storage heaters and with a reasonably well insulated house it can work fine, I would not change back.

I am aware of some folk locally not happy with it in older poorly insulated homes.

 

[DAPPH]

I think i'll bite the bullet this year and rip out the air source and fit a combi running off propane with an underground tank.

The quotes to make good the ASHP system are huge, and i'm not convinced throwing more money at it will fully resolve.

LPG is just about the most expensive form of boiler fed central heating you can get .

 

[DAPPH]

Quite unbelievable my post appears to have been deleted as I broached an unpalatable truth.

ASHP work fine if the building is fit for it. I know a number of folk who've built their own places and exceeded passive house standards in some cases. Paul said his place is well insulated and to current regs. Unfortunately mass builders don't necessarily understand the importance of getting insulation and airtightness right and results are often fudged for sign off. The folk I know are anal about it. The result is an ASHP that works and really well. Some even use theirs for slab cooling in summer.

Got an acquaintance a hundred yards from here who has had his family tradesmen build his super efficient recirculated filtered air GSHP powered system . last time I saw him in winter two years ago he reckoned his monthly heating bill was below £20 .

I was impressed when I saw the certifying engineers pump up the house and see that it was holding the pressure tests for almost double the required time.

 

[DAPPH]

You posted endlessly regurgitated and irrelevant nonsense

This post (as you now state) involves a new build, yet you continue with the nonsense

Fabric first is important, but understanding system design, building use and heat pumps is much more important

I have installed and I am currently planning to install heat pumps in buildings that are scheduled ancient monuments, the ones that need the secretary of state's approval to work in

We categorically cannot alter the fabric, yet the heat pumps work exactly as designed, providing the correct level of comfort and hot water, while removing the need for fossil fuels

To be fair, the design alone probably costs 10 X that of a domestic install, but yeah, fabric first is the only approach

Isn't what you are really talking about simply putting in a massive calculated size heat pump to compensate for building inefficiencies and heat losses to a temp of minus 15 oC or so ?

 

[DAPPH]

Yes, you can do a cascade system. The usual approach is an air source first then a water source, but there would be no reason you couldn't use any 2 technologies together based on site requirements

I'm still involved in ground source, just do a lot more as well these days

Working on a 1.5MW system right now, boreholes will be going under a rugby pitch before it is relaid

Have you done any boreholes inside a new build flooring plan say five or six boreholes linked to a control manifold etc. Saw one such system being installed as an experimental set up in a new build ..don't know the follow up results . do you have any information on such things ?

 

[Kayos]

Isn't what you are really talking about simply putting in a massive calculated size heat pump to compensate for building inefficiencies and heat losses to a temp of minus 15 oC or so ?

No, because at the point there isn't a net energy saving the project is pointless. Most gas and oil heating is massively oversized

 

[Kayos]

Have you done any boreholes inside a new build flooring plan say five or six boreholes linked to a control manifold etc. Saw one such system being installed as an experimental set up in a new build ..don't know the follow up results . do you have any information on such things ?

Yes, I have fitted many systems like this, they are not experimental, rather proven working systems

 

[DAPPH]

Yes, I have fitted many systems like this, they are not experimental, rather proven working systems

Got any company names to look at that you'd use?

 

[Kayos]

Kensa Contracting, and Hex Energy are 2 I know well

I used to work for Kensa