Ground Source Heat Pumps

beardymarrow

sueda said:

Hello. I've just joined here and this is my first post and am hoping for some advice please. Here's our situation:
My husband and I live in a 2 bed bungalow of modest proportions (approx 12m x 10m) and as we live in the country we have oil to heat the property. However, we are just about to convert a substantial barn on the same site (a double height barn (18m x 6m but with upstairs rooms), with a single barn attached (20m x 7m). We would like to change from oil for the bungalow and install ground source to supply both the new build barn and existing bungalow, if possible. At this point, I'd state that we have erred towards ground source rather than air source based on limited research and a few conversations with people. We would like to house the plant machinery (is that the right term??) in the garage and install the curly pipework in the 4 acre field next to the garage (enough for the pipework, I'm guessing?). The barn is 40m away from the garage and the bungalow is 60m away. We are also considering installing solar panels on the garage roof. The questions rolling around our head, keeping us awake :-):
1 Is this length of pipework (40m and 60m) acceptable/ viable?
2 An estimated cost of installation?
3 Recommended companies, based on price/ value and quality?
4 Best pump for the job for both properties (if applicable)?
5 Estimated bills?
6 Estimated payments (from the RHI?)?
7 Re the barn, would it work best with radiators or underfloor heating, or combination?
8 What grants may be available?
9 Can we have a grant for both solar and ground source?
10 Is energy stored? Can it be used later?
11 We have power cuts occasionally, does that have an impact?
Apologies for all of the questions and my naivety on this subject. Any help and advice greatly appreciated. 
PS If there are any other alternatives that might be considered please feel free to advise. Many thanks.

Hi Sueda, 
I've got a fair bit of experience operating my GSHP, but it was installed before we moved in so the install side I don't know that well. I'll attempt to answer what I can. 
1. Do you mean the pipe work from the GSHP to the radiators/UFH? I would guess you'd get a lot of heat loss on a run that long, especially as it sounds like it would be outdoors. If I was you I'd build a little boiler room on the side somewhere where it was close to both places. 
7. UFH plus towel rail in bathroom, unless there's some reason you can't install it underfloor. It's a lot more efficient and runs at lower temps than rads, so much better suited to a GSHP.
10. Somewhat as you should have a buffer tank on the UFH to smooth out demand on the GSHP. It's more efficient if the GSHP is running for longer times less frequently, rather than cycling on and off quickly like a conventional boiler would . Also you'd have a hot water tank for DHW as a GSHP would never produce enough instant hot water.
11. Less than for a conventional boiler. Obviously you'd not be producing any heating or hot water when power was off, but with a hot water tank and UFH you'd not get cold really quickly like you would with a conventional boiler and rads. A conventional boiler would need electricity to work as well. 

beardymarrow

Fort_2 said:

Thanks for your response. 

It is itv greenline c. 

Have a look here for the parts https://jsenergi.co.uk/ivt-spare-parts/by-model.html?gclid=Cj0KCQjw-uH6BRDQARIsAI3I-Uc2xYrvH-kXzgbPM9o-wpi2yPTElUWwupa6D3_VrkXvS2QNmC033zMaAlNOEALw_wcB. I think it would be this one https://jsenergi.co.uk/ivt-spare-parts/by-model/ivt-greenline-c4-1x230v-uk/3-port-valve-ivt-lk-vxv525-22-engine-emv110m-before-2008.html. You might find it cheaper elsewhere. I doubt it, but worth checking. Easy job for any plumber to do. 

Fort_2

beardymarrow said:

Fort_2 said:

Thanks for your response. 

It is itv greenline c. 

Have a look here for the parts https://jsenergi.co.uk/ivt-spare-parts/by-model.html?gclid=Cj0KCQjw-uH6BRDQARIsAI3I-Uc2xYrvH-kXzgbPM9o-wpi2yPTElUWwupa6D3_VrkXvS2QNmC033zMaAlNOEALw_wcB. I think it would be this one https://jsenergi.co.uk/ivt-spare-parts/by-model/ivt-greenline-c4-1x230v-uk/3-port-valve-ivt-lk-vxv525-22-engine-emv110m-before-2008.html. You might find it cheaper elsewhere. I doubt it, but worth checking. Easy job for any plumber to do. 

Thanks, just bought it. 

Will be replacing It myself. I believe it all goes same way as old was fitted. 

beardymarrow

Fort_2 said:

beardymarrow said:

Fort_2 said:

Thanks for your response. 

It is itv greenline c. 

Have a look here for the parts https://jsenergi.co.uk/ivt-spare-parts/by-model.html?gclid=Cj0KCQjw-uH6BRDQARIsAI3I-Uc2xYrvH-kXzgbPM9o-wpi2yPTElUWwupa6D3_VrkXvS2QNmC033zMaAlNOEALw_wcB. I think it would be this one https://jsenergi.co.uk/ivt-spare-parts/by-model/ivt-greenline-c4-1x230v-uk/3-port-valve-ivt-lk-vxv525-22-engine-emv110m-before-2008.html. You might find it cheaper elsewhere. I doubt it, but worth checking. Easy job for any plumber to do. 

Thanks, just bought it. 

Will be replacing It myself. I believe it all goes same way as old was fitted. 

Nice, yeah it's dead easy to do. Just remember that the water inside will be under pressure if you need to replace the valve as well as the motor :-)

Fort_2

Yes i am replacing valve with motor, they said it would only need to be plugged back with old cable. 

I will need to close water supply and drop   

Pressure for hot water by opening taps to drain what is in the pipes and do the same for heating end. 

Right?  

Thanks for advise. 

beardymarrow

Fort_2 said:

Yes i am replacing valve with motor, they said it would only need to be plugged back with old cable. 

I will need to close water supply and drop   

Pressure for hot water by opening taps to drain what is in the pipes and do the same for heating end. 

Right?  

Thanks for advise. 

Yeah, exactly,and you're right the old cable just plugs straight in.

Fort_2

Was checking temperature readings and
a bit confused as why gt1 is showing -on 17.5 now 37.7. 

But i have no heating needed only hot water. Why would return temperature would be so high? 

beardymarrow

Fort_2 said:

Was checking temperature readings and
a bit confused as why gt1 is showing -on 17.5 now 37.7. 

But i have no heating needed only hot water. Why would return temperature would be so high? 

That is high. My GT1 spikes to 31deg when the GSHP is providing DHW and the rad pump is off (i.e. no flow of water past the GT1 sensor), which is just because of heat transfer up the copper pipe to the sensor as the rad and DHW circuit will have a common return point into the Heat Fluid Pump (P2). If your 3Way is stuck, you could also be getting some water going round the rads when it should only be providing DHW.

Fort_2

I thought this could be due to faulty valve. 

Could it be that sensor is fitted too close to unit?  How far from unit should the sensor be? 

beardymarrow

Could be faulty valve, or could be too close (or a combination of both). The manual says "Install flow line sensor T1 in direct contact with the flow line pipe, approximately 1-2 meters from the heat pump and preferably at a 90º bend (horizontally).". It should always be before the bypass (if you have one) as well.