Which domestic GSHP

[D14]

Any suggestions for a GSHP for a 4 bedroom farm cottage please? The cottage was renovated around 20 years ago so its insulated etc and still in very good condition. It'll get a mini overhaul within the next 5 years and possibly an extension on the ground floor and a loft conversion at the same time. When its been overhauled it will end up at 2750 sqft if that makes any difference to the pump size. The present boiler has about had it so the idea is to sort that our now and put a GSHP in before the tariffs go next year. So it would literally just plug into the current heating system now but when the house is overhauled we will do underfloor heating etc.

 

[akaPABLO01]

Any suggestions for a GSHP for a 4 bedroom farm cottage please? The cottage was renovated around 20 years ago so its insulated etc and still in very good condition. It'll get a mini overhaul within the next 5 years and possibly an extension on the ground floor and a loft conversion at the same time. When its been overhauled it will end up at 2750 sqft if that makes any difference to the pump size. The present boiler has about had it so the idea is to sort that our now and put a GSHP in before the tariffs go next year. So it would literally just plug into the current heating system now but when the house is overhauled we will do underfloor heating etc.

You can’t stick a wet finger in the air, gshp depends on soil type and how many slinkies you need to capture the heat. You can have a buffer uplift for future conversions meaning you think you’ll need more heat in the future. Beware though, I get told this all the time “garage conversion, loft conversion, extension”. I only go about 10% more depending on where the property falls in heat pump banding, for example,

The .pdf I posted somewhere here is about 11.6kW with 9 slinkies. I chose the 13 for a future garage conversion but I could have got away with an 11.
The soil is sandy, poor thermal conductivity so requires more pipe, could have used maybe 6/7 slinkies but then you’re cutting corners. Right first time.

My wet finger guess
11kW gshp
6/8 slinkies
Loft insulation up to 270mm
150l buffer maybe less
Hmmm, 250 or 305l cylinder
Secondary return - difficult to install in your case but part of platinum install if you don’t have one.

Ermmm, I’ll guess at £16k no civils, no rads, no carcass mod.

Payback with another wet finger...£23k

 

[D14]

You can’t stick a wet finger in the air, gshp depends on soil type and how many slinkies you need to capture the heat. You can have a buffer uplift for future conversions meaning you think you’ll need more heat in the future. Beware though, I get told this all the time “garage conversion, loft conversion, extension”. I only go about 10% more depending on where the property falls in heat pump banding, for example,

The .pdf I posted somewhere here is about 11.6kW with 9 slinkies. I chose the 13 for a future garage conversion but I could have got away with an 11.
The soil is sandy, poor thermal conductivity so requires more pipe, could have used maybe 6/7 slinkies but then you’re cutting corners. Right first time.

My wet finger guess
11kW gshp
6/8 slinkies
Loft insulation up to 270mm
150l buffer maybe less
Hmmm, 250 or 305l cylinder
Secondary return - difficult to install in your case but part of platinum install if you don’t have one.

Ermmm, I’ll guess at £16k no civils, no rads, no carcass mod.

Payback with another wet finger...£23k

So spend £16k plus civils to get £23k back in tariff then there is the money not spent on kerosene to take into account as well?

 

[akaPABLO01]

So spend £16k plus civils to get £23k back in tariff then there is the money not spent on kerosene to take into account as well?

Correct unless the Kero is used somewhere else, auger?

 

[ashelton]

Why move thousands of tonnes of soil when you can use a trencher which cuts down on installation costs and time. Recovery and settlement is reduced.

For more information call me on 01507 578288 / 07734531227

 

[scotston]

What depth?

 

[ashelton]

What depth?

The CT150 will dig upto 1.5m (5 feet) deep and from 145mm - 320mm wide.
The picture above of the trenches we dug yesterday are 210mm wide and 1050mm deep.
We have found that the trenches back fill a lot better at this width even though the arisings are friable.