180m borehole cost per metre for ground source heat pump

[Strak]

7 hours ago, ReedRichards said:

For an ASHP, cooling is not allowed without explicit planning permission.  If you don't do cooling then an ASHP may be a permitted development.

 

Any idea of the criteria used to decide if the planning application is approved or not?

 

3 hours ago, joe90 said:

This does seem daft, is there a practical answer as to why 🤷‍♂️

 

Agree, I can't put my finger on why this would be. There must be some convoluted logic to explain it, but I don't know what it is!

[joe90]

I have to ask, how would BC know the ASHP was configured to cool, others here have said all ASHP,s can be reverse engineered to provide cooling 🤷‍♂️

[sharpener]

On 26/04/2024 at 09:58, Strak said:

Products that are delivered at the factory with no cooling mode are labelled with "S2" in the nomenclature.

 

I think the S2 models are what are shipped to the UK market. The installation manual on the Midsummer website is specifically for those variants. It has come up in the past on the Arotherm plus FB page.

[Strak]

7 hours ago, sharpener said:

Arotherm plus FB page

Thanks for that link - useful page, and interesting ideas about using fancoil units for cooling.

[JohnMo]

47 minutes ago, Strak said:

Thanks for that link - useful page, and interesting ideas about using fancoil units for cooling.

Fan coil work well for cooling and heating. Be aware they have a fan, the noise from that can be affected by the quality of unit you buy - you get what you pay for. Also they generally use a fixed flow temp so no need for weather compensation, just set the flow temp at 30 to 35 depending on how you size the fan coil units, the fan coil control does the rest.

 

Vaillant units are good, but very expensive, an R32 unit can be just as good for way less money - if you don't need high flow temperatures, and a heating system that needs high temperatures shouldn't have a heat pump attached anyway.

[Strak]

13 minutes ago, JohnMo said:

Fan coil work well for cooling and heating. Be aware they have a fan, the noise from that can be affected by the quality of unit you buy - you get what you pay for

 

Ahh I see. I mentioned cooling as the posts I had seen were people using underfloor heating zones for heating, and fan coil as cooling zones only I think. Is efficiency lost in using air rather than ufh, or is that choice likely to be related to noise?

 

If I need a 6kw heat pump to heat my house, should that also be capable of cooling the same space to a useful level? 

 

I've also started reading up on heat recovery systems (might end up as another thread on here!) - can they share the same ducting as the fan coil units?

[Nickfromwales]

17 hours ago, ReedRichards said:

For an ASHP, cooling is not allowed without explicit planning permission.  If you don't do cooling then an ASHP may be a permitted development.

Says who? Done cooling on the majority of my client new build projects, and all have been certified without question. Even with the RHI you could cool as long as you had a heat meter installed so it could be 'calculated'.

[Nickfromwales]

@Strak I removed the borehole survey link as it shows personal info that scammers may abuse. Please add a picture of the survey with details anonymised if you can / want to.  

[Nickfromwales]

57 minutes ago, Strak said:

 

Ahh I see. I mentioned cooling as the posts I had seen were people using underfloor heating zones for heating, and fan coil as cooling zones only I think. Is efficiency lost in using air rather than ufh, or is that choice likely to be related to noise?

 

If I need a 6kw heat pump to heat my house, should that also be capable of cooling the same space to a useful level? 

 

I've also started reading up on heat recovery systems (might end up as another thread on here!) - can they share the same ducting as the fan coil units?

Another thing with GSHP's with anything other than a borehole, you can't do cooling as they cook the ground and it shrinks away from the loop (so when you need heating the ground loop is less (very much) effective).

 

Cooling needs a bit of human influence, prediction, and planning in its execution imo. Just having it working away in the background, in anticipation, is a better strategy than just 'switching it on' as the damage is usually then already done (house has become uncomfortably warm / hot) and then there is a huge amount of energy to shift. These types of heat / cool arrangements don't react anywhere near as quickly as A2A (air to air) A/C can, so beware making uniformed choices which then are integrated into the fabric of the build and then cannot be altered / changed retrospectively without huge costs and disruption etc.

 

Fan coils are noisy, but so is A/C, so decide which services your home best; if you already have an ASHP for heating (that can cool) then use that + "cold" UFH + fan coils in that ascending order to do the same job. A full PHPP analysis should show you what your overheating risk is (as a %), and this should be known, understood and investigated, before designing / specifying diddly-squat!

 

"Fail to prepare...."

[Strak]

7 hours ago, Nickfromwales said:

@Strak I removed the borehole survey link as it shows personal info that scammers may abuse. Please add a picture of the survey with details anonymised if you can / want to.  

Ok - it was just a link to a survey that is publicly available I came across when looking for surveys in this area, but I extracted the important text about the ground makeup anyway and put it in the post so all good 🙂

[Strak]

7 hours ago, Nickfromwales said:

Cooling needs a bit of human influence, prediction, and planning in its execution imo. Just having it working away in the background, in anticipation, is a better strategy than just 'switching it on' as the damage is usually then already done (house has become uncomfortably warm / hot) and then there is a huge amount of energy to shift

Good tip, thanks. I I have seen that some controllers are able to look at weather forecasts, and wondering if they would help here. From the Vaillant site:

Weather compensation is technology that uses environmental data to understand the thermal behaviour in and around a property. The weather compensation feature on Vaillant’s smart controls uses weather forecast data to understand the outside temperature. It then adjusts the heat going to the radiators or underfloor heating system for optimum efficiency.

 

7 hours ago, Nickfromwales said:

A full PHPP analysis should show you what your overheating risk is (as a %), and this should be known, understood and investigated, before designing / specifying diddly-squat!

 

I have no idea how to go about doing that! Is that something I should expect an installer who's designing the system to be able to help with? I've only had a heat loss survey so far.

 

I also visited a family friend recently who's done a full refurb of their house, and was really happy with his choice to install a heat recovery system. I haven't yet posted about that, but wondering if a fan coil for cooling would be something that I add later into that system if needed. The fan coil units I'd want to put in this place would be the units for ducting, so only vents in the actual rooms - I don't know if that makes much difference to the noise level?

[JohnMo]

18 minutes ago, Strak said:

have seen that some controllers are able to look at weather forecasts, and wondering if they would help here.

If you want weather compensation almost all do it straight out the box, you don't need internet connected anything for it.

 

Are you doing a new build or refurbishment?

 

 

[Strak]

8 minutes ago, JohnMo said:

If you want weather compensation almost all do it straight out the box, you don't need internet connected anything for it.

 

Are you doing a new build or refurbishment?

 

 

It's a refurb with an extension and loft conversion, pretty significant changes to the layout of most of the house.

[sharpener]

2 hours ago, Strak said:

The fan coil units I'd want to put in this place would be the units for ducting, so only vents in the actual rooms - I don't know if that makes much difference to the noise level?

 

We have a Villavent 400 MVHR system with inlets in the bedrooms and extract points in bathrooms and kitchen. The noise on medium speed is perceptible but not a nuisance. It is on a timer for setback at night, when it is almost inaudible. When frying we put it on boost which is noticeable in the kitchen (but not as bad as a fan hood or the control panel cooling fan in the cooker(!)).

 

You can get fancoil heating units to put in the ducting, I don't know if they work for cooling, you would need to do sth about condensation.

 

To keep the ductwork clean we have added bonded acetate fibre filter discs to all the extract points which we change every 6 months, they collect a lot of cooking spatter and towel fluff, I am surprised they are not a standard fitment.

[JohnMo]

4 minutes ago, sharpener said:

fancoil heating units to put in the ducting, I don't know if they work for cooling

Flow rate through MVHR is out by a factor of 10 to useful for cooling. Heating is only useful at passivhaus heat demand levels - 10W/m2. Otherwise it burns the dust in the air.

 

6 minutes ago, sharpener said:

acetate fibre filter discs to all the extract points

We use similar but like a cone shape, they come with 10 to 15mm of dust attached after 6 months.

 

8 minutes ago, sharpener said:

timer for setback at night

Don't you find you CO2 levels get a bit high in the bedroom doing that? Or do you have the bedroom window open?

[sharpener]

9 minutes ago, JohnMo said:

Flow rate through MVHR is out by a factor of 10 to useful for cooling.

 

Yes I now remember I did some sums and would have needed 12in ducts to bring enough air in for complete heating/cooling. Might be useful as a topup or for specific rooms I suppose.

 

9 minutes ago, JohnMo said:

Don't you find you CO2 levels get a bit high in the bedroom doing that?

 

OH likes fresh air and would have all the windows open given a chance. OTOH I would wake up with a headache if the CO2 level was too high. Michael Podesta has written about using CO2 levels to assess air changes/hr on his blog protonsforbreakfast but I was more confused after reading it than I was to start with. And am normally quite numerate.

 

Edited April 28 by sharpener

[SteamyTea]

3 minutes ago, sharpener said:

needed 12in ducts

Is that diameter?

Or 300mm on each side.

 

4 minutes ago, sharpener said:

Michael Podesta has written about using CO2 levels to assess air changes/hr on his blog protonsforbreakfast

Trouble is that not many experiments that test just for different CO₂ variation. Most 'tests' are done without taking humidity and temperature into account properly.

Then they need to be repeated hundreds of times.

Very hard to to in a double blind, randomised fashion.

 

But it don't matter, people will believe that it is the CO₂ as they think they can control that easily and it is the only thing that can make a difference.

[JohnMo]

20 minutes ago, sharpener said:

likes fresh air and would have all the windows open given a chance

We had -1 the other night and zero last night, our bedroom door shut window open, nice temperature bedroom.

[ReedRichards]

On 27/04/2024 at 10:31, joe90 said:

This does seem daft, is there a practical answer as to why 🤷‍♂️

 

The justification I have seen is that in summer your neighbours will have their windows open and will not want to be disturbed by the sound of somebody else's heat pump being used for cooling.  In winter their windows will be closed so noise is not so much of an issue.  Anyway (from https://www.planningportal.co.uk/permission/common-projects/heat-pumps/planning-permission-air-source-heat-pump )

 

 

Quote

 

In addition, the following conditions must also be met. The air source heat pump must be:

• Used solely for heating purposes
• Removed as soon as reasonably practicable when it is no longer needed for microgeneration
• Sited, so far as is practicable, to minimise its effect on the external appearance of the building and its effect on the amenity of the area.

 

 

 

So if you install a heat pump without planning permission, use it for cooling and a neighbour objects to the noise then you could try a retrospective application for planning permission but in view of the objection this might get turned down.

Edited April 28 by ReedRichards

[joe90]

16 minutes ago, ReedRichards said:

So if you install a heat pump without planning permission, use it for cooling and a neighbour objects to the noise then you could try a retrospective application for planning permission but in view of the objection this might get turned down.

However, the objection has to be relevant (excess noise levels measured) and how will a neighbour know the heat pump is being used for cooling? My heat pump was timed to heat DHW in the warmest part of the day. Also I have a neighbour now that has an oil boiler that is way noisier than my heat pump was.

[joe90]

This copied from another thread re planning portal….equivalent standards ?

 

• Development is permitted only if the air source heat pump installation complies with the Microgeneration Certification Scheme Planning Standards (MCS 020) or equivalent standards. Read more about the scheme.

[ReedRichards]

23 minutes ago, joe90 said:

how will a neighbour know the heat pump is being used for cooling?

 

Well a heat pump on for a long period of time on a hot day would be a big clue.  I'm not saying this rule is sensible but it is a rule you have to follow if you want to install a heat pump as a permitted development.  Or you could ignore it - but might have to face the consequences.

 

"MCS Planning Standards or equivalent" is a whole other can of worms.

[ReedRichards]

13 hours ago, Nickfromwales said:

Says who? Done cooling on the majority of my client new build projects, and all have been certified without question. Even with the RHI you could cool as long as you had a heat meter installed so it could be 'calculated'.

 

Says the regulations for installing a heat pump as a permitted development.  So of course this doesn't apply to new build projects where the whole development needs planning permission and the grant of planning permission encompasses the heat pump.  

[JohnMo]

10 minutes ago, ReedRichards said:

heat pump on for a long period of time on a hot day would be a big clue.

But in cooling mode especially with flow temps of 15 (suitable for UFH) power input is tiny, so running speed and noise is also on the very low side. Last summer I had to walk right next to the heat pump to see if it was doing anything. 25 degree day and 15 flow, the unit is doing an EER of 6+, so next to no work.

[ReedRichards]

Just now, JohnMo said:

But in cooling mode especially with flow temps of 15 (suitable for UFH) power input is tiny, so running speed and noise is also on the very low side. Last summer I had to walk right next to the heat pump to see if it was doing anything. 25 degree day and 15 flow, the unit is doing an EER of 6+, so next to no work.

Yes, but this is the actuality of cooling, not what somebody in an office devising regulations thought it might be like.  But I agree that it means you should get away with it without your neighbours noticing (as necessary).