GSHP installer, Cheshire

[optic]

Looking for someone to advise and install and GSHP in the Cheshire area (Northwich), house is currently undergoing full renovation, have approx 300M2 of garden to put a collector house is being insulated 75mm internal insulation and 60mm cavity, 140M2

Cheers

Charles.

[A.L.]

hello and welcome,

300m² - will only support a 6kw heat pump, and since you probably cannot use all of it probably significantly less.

if you have good draught proofing you could probably get away with 4kw if you were prepared to heat continuously, preferably with ufh,

but any sort of on/off heating regime is probably out

[optic]

Hi 300m2 is what i can use i've not counted the area for drive and future garage etc, the area is in mainly unshaded so should be good for solar gain at not too much depth, there is a small pond at the end of the garden approx 100m2 which i'm sure the farmer would not notice a coil chucked in, don't know how deep it is though. also need to put in a 50m trench for the pumped water treatment plant so could put and run of pipe in that trench but must not freeze the pipe.

New floor going in down stairs with 200-250mm of insulation and ufh pipe on the concrete reinforcing mesh, upstairs fully ufh planned,

I think i could live with 6Kw, don't have a clue on DWH tank sizing, ruled out thermal store due to temp loss, don't know what size buffer tank i'll need etc.  have a 5Kw stovax for the the front room that i may make a back boiler tank for, future plan is a aga in the kitchen so need to account for that, Solar thermal for summer hot water would be a long term option too.


Need to find out heat pump sizing and pipe layout as will have the digger coming soon to install water treatment plant and rain water tank,  do you think it's worth trying to get an approved installed system to maybe claim the Fit or what every they are coming up with next year

[A.L.]

If the rest of the house is insulated to same standard as walls and floor you will not need heating in upstairs bedrooms, except maybe on-suites.

i'm sure the farmer would not notice a coil chucked in

- a coil would not make any significant contribution, generally extracting heat from small fixed bodies of water is not advised, it just makes them freeze up.

50m trench for the pumped water treatment plant so could put and run of pipe in that trench but must not freeze the pipe.

- dig down to a GSHP loop in Jan/Feb and you will find it encased in ice, so no, keep it around 2 metres away to be safe, apply a similar distance from any foundations (frost heave)

Solar thermal for summer hot water would be a long term option too

- if you pick a GSHP with a 60/65C flow capability you will not need solar thermal

5kw output in one room and AGA in kitchen will, even seperately, produce local overheating without careful ventilation

[optic]

Thanks for the reply, good info there, the navitron does not do 65 degree output from what i can see what other models are out the I've googled but ill i seem to find are company's wanting big bucks,

I've had a look at the plot again and it's more like 575m2 i can use, maybe even a bit more, would the 32mm hdpe pipe that is on ebay be ok? £300 per 300m, it's not in loops but that won't take long.  

We are in sold clay the pond is about 2m down so thats where the water table will be, going to have to put some land drainage in as we allready have some standing water. what depth do you recommend ?


And yes the 5kw stove in our old house was too much for the 20m2 room and having the doors open made drafts but would keep the 75m2 semi house warm in winter.  

all external walls on the original house will have internal insulation and new extension with 100mm cavity,

The kitchen will be 6 x6 metres and has to have an aga, i'm going to run the pipes in for mechanical ventilation also,

i thought i would have to have ufh upstairs if i was using a gshp and with the water temp being low ?

[Ivan]

I think Navitron can supply high temperature output heatpumps if you require it (using Kensa brand) - but we'll need to check with Kensa which model, as usually heat pumps are restricted to lower outputs to keep the efficiency high. But you're probably better using lower temperature and boosting with immersion heater/solar thermal/woodstove as required. Most solar thermal systems are capable of reaching operating temperature for most days over 6months or so of summer - much cheaper than running a heatpump for 60C hot water. Woodstoves can do the job the rest of the year, with immersion heater for backup.

[A.L.]

hello again optic, - sorry I seemed to have missed your last reply

The kitchen will be 6 x6 metres and has to have an aga, i'm going to run the pipes in for mechanical ventilation also,

With an 80% efficient MVHR your kitchen heatloss at 0°C is going to be around 500watts so compare this with your AGAs output

i thought i would have to have ufh upstairs if i was using a gshp and with the water temp being low ?

With no actual insulation between ground and first floors heat transferring through the ceiling/floor and up the stairs in heavily insulated houses will keep upstairs rooms within 2°C of downstairs rooms. The only question is do you want any 'on-suites' to be warmer?

[optic]

Just an update got a IVT 7Kw heat pump on order from ice energy, all the local companies all sound great on the phone but once you mention you have installed the ground loop yourself you don't get any of the promised calls back !! must be a big part or there profit to install the ground loop.

AL yes i worked out the heat loss of 1kw ish including 20 loss through MVHR, just adding up the areas and u numbers of all the materials with a 25 degree temp difference, house worked out as 4Kw but no doubt alot worse with thermal bridging etc, but should be approx 18% better then current building regs with standard double glazing,

regards