New GSHP Efficiency?

kwoodberry

markin said:

MikeJXE said:

MattMattMattUK the pipes were installed as slinkys. To you and me a 'slinky' is simply a coiled pipe acting as a heat collector laid in an array of 4no. 1m deep trenches x 60m long.

I don't know a single thing about heat pumps but I do know about trenches

Is 1m deep enough ?

I have worked in many trenches and you don't get any heat at 1 metre, heck water services have to be 75cm deep or they are liable to freezing 

I would have thought 2m or 2.4m would have been a minimum depth as I know it's much warmer there ? 

It did sound a little shallow to me but it must be ok as its getting an average COP of 3.96.

@markin - My mistake, the trenches were 1200mm wide by 1200mm deep and the slinky's were laid flat on the bottom of the trenches.

Mstty

kwoodberry said:

Unfortunately, there are no historical records of consumption as the house is a new-build with a new electric meter. So the usage only really started end of June 2022 when we moved in (apart from the small consumption of lighting and charging trades power tools).

However, I did find the consumption of the GSHP. There's a small display under the main cover.

It reads 5193 kWh to date.

Bearing in mind, the GSHP was fitted new around April 2022, and was only really used from June to October for Domestic Hot Water, the space heating side of it has only really been running since late October 2022.

Would you say this is "as expected" consumption, or high, considering the leccy meter only reads 12352 kWh (as of yesterday)?

I will check the GSHP consumption screen weekly as I make the odd tweak, like reducing the amount of time the DHW is set to come on for.

Although eye watering. For us with our ASHP we also only heated hot water in summer and it's been going fully from mid November onwards on the weather compensation curve.

Going by your GSHP meter (great you have found it as you take regular readings for any changes you make) you might expect to use 9400kwh a yeah on heating and hot water extrapolating your given figure and usage out.

Given your square meterage of the property and Vaulted areas? Probably not a million miles off but some efficiencies when you get to know your GSHP could bring that figure down 10-20% like we did in our first year.

ec000

If it makes it any better, our house is about 3500 sq ft and the rooms are cold (16/17 ish), and at this time of year we’re using 45-60kWh a day. GSHP with two bores, installed c2016.

So I think you’re doing ok. Even better when the price differential between gas and electricity gets sorted out.