Ground Source Heat Pumps

ccbrowning

It is some electrical problem, so they've temporarily just turned on the immersion tank's small 3.4kW heating unit. At least that is on a timer so I can just have it on when the sun is out until they fix whatever is wrong with the heat pump.

ccbrowning

GSHP still broken! Brill... luckily the immersion tank's heating element is basically free during the summer since I just turn it on for like 30 min when the sun is out.  

Thinking ahead to when the GSHP is fixed and heating is going to get turned on again this autumn... How many hours a day are you all needing to run you GSHP for heating purposes? Can you get away with just having the heating of the water happening a few hours during mid-day? My use case is a very-well insulated new home with only underfloor heating.

beardymarrow

On very cold days mine can be on nearly 24hrs, with occasional boost from the electric cartridge. 18th Jan for example 23hrs heat pump (of which 2.5hrs was 5 periods of DHW) plus 2hrs additional heat from the cartridge. 31st Dec was 10hrs (of which 2hrs 43 was 6 periods DHW) . 

ccbrowning

beardymarrow said:

On very cold days mine can be on nearly 24hrs, with occasional boost from the electric cartridge. 18th Jan for example 23hrs heat pump (of which 2.5hrs was 5 periods of DHW) plus 2hrs additional heat from the cartridge. 31st Dec was 10hrs (of which 2hrs 43 was 6 periods DHW) . 

Wow, ok.

We moved in mid-feb and our first full month was March where we used 710 kWh (not checked our PV stats for the month to see what -real- usage was tho). I seem to remember it being colder and more wet than usual. However, I know they left the it on the 24/7 setting instead of using the internal timer to prefer daylight hours.

beardymarrow

Mind you, we only have ufh in half the ground floor, not the rest. March average was 42kwh (11hrs ish) per day, so approx 1200 kwh for the month.

Anyway, hopefully gives you an idea/rough comparison. 

ccbrowning

beardymarrow said:

Mind you, we only have ufh in half the ground floor, not the rest. March average was 42kwh (11hrs ish) per day, so approx 1200 kwh for the month.

Anyway, hopefully gives you an idea/rough comparison. 

Thanks so much. Amazing the variation - quite a few variables I guess! 2200 sq ft, UFH over both floors, modern insulation, + 3.4kW pv. 

beardymarrow

ccbrowning said:

beardymarrow said:

Mind you, we only have ufh in half the ground floor, not the rest. March average was 42kwh (11hrs ish) per day, so approx 1200 kwh for the month.

Anyway, hopefully gives you an idea/rough comparison. 

Thanks so much. Amazing the variation - quite a few variables I guess! 2200 sq ft, UFH over both floors, modern insulation, + 3.4kW pv. 

Yeah, exactly. Ours is 3000sqft. UFH in half the ground floor, rads the rest. Modern insulation. No PV. I'd say our kwh usage seems comparable given the slightly larger size, less efficient use of rads and no PV.

Patrol

This is approx how many hours a day my ground loop is on, I tend to take 1-2 readings a month but am not good at doing the same day every month so a lot of 2-6 week gaps.

2041 hours at about 1-4 to 1.7 units an hour depending on COP.

Jul 1
Aug 1.3
Sep 1.3
Oct 3.5
Nov 5
Dec 11
Jan 14
Feb 10
Mar 6
Apr 6
May 1.5
Jun 1.4

Plus 9 hours additional heat over the year (54 units).

ccbrowning

Does anyone know a competent company for GSHP service etc in the Preston area?

And @Patrol , what is a unit?

Patrol

Units on the meter, so kWh