Ground Source Heat Pumps

poohbear59

beardymarrow said:

poohbear59 said:

My husband went there and returned off the heat pump. Left it off while he was working in there. Switched it back on and now it is working..
Magic!

It was off a lot longer than when I switched it off a few days ago. 

Thank you very much for your assistance Beady.

Awesome. So glad you're back up and running. 

It is wonderful to have warmth again. Thank you again.

lstevensuk

Question before I start to put some tiles down!

My UFH system came with a 2 port motorised valve (reliance 22mm 250305). However this was never fitted as I wasn't able to wire it back to the heat pump. I've now realised I could potentially sneak the wite along the top of 25mm insualtion around the floor edge and maybe get it back to the pump. I'd need to do that before I get the tiles down. Is this going to benefit me in anyway bearing in mind I have radiators and the UFH currently all on the same run? Thanks!

p.s. Hope eveyones kwh's are starting to go down with the warmer weather now

beardymarrow

lstevensuk said:

Question before I start to put some tiles down!

My UFH system came with a 2 port motorised valve (reliance 22mm 250305). However this was never fitted as I wasn't able to wire it back to the heat pump. I've now realised I could potentially sneak the wite along the top of 25mm insualtion around the floor edge and maybe get it back to the pump. I'd need to do that before I get the tiles down. Is this going to benefit me in anyway bearing in mind I have radiators and the UFH currently all on the same run? Thanks!

p.s. Hope eveyones kwh's are starting to go down with the warmer weather now

Hiya, That valve won't work with the heatpump as you need a 3 port mixer valve (ESBE VRG130 with ARA672 actuator for example), but DEFINITELY run a wire back to the heat pump for a valve (3 core) for future and also you'll need a 2 core wire for the temperature probe. For the cost of doing it now, you'll regret not doing in future when you decide to wire a valve in, but can't dig your floor up :-)

Having the rads and the UFH on the same run is fine, because you would use the 3 port mixer to blend some of the cooler return water from the UFH back into the feed for the UFH, so that the UFH runs cooler than the rads. That's the normal way of doing things anyway.

lstevensuk

beardymarrow said:

lstevensuk said:

Question before I start to put some tiles down!

My UFH system came with a 2 port motorised valve (reliance 22mm 250305). However this was never fitted as I wasn't able to wire it back to the heat pump. I've now realised I could potentially sneak the wite along the top of 25mm insualtion around the floor edge and maybe get it back to the pump. I'd need to do that before I get the tiles down. Is this going to benefit me in anyway bearing in mind I have radiators and the UFH currently all on the same run? Thanks!

p.s. Hope eveyones kwh's are starting to go down with the warmer weather now

Hiya, That valve won't work with the heatpump as you need a 3 port mixer valve (ESBE VRG130 with ARA672 actuator for example), but DEFINITELY run a wire back to the heat pump for a valve (3 core) for future and also you'll need a 2 core wire for the temperature probe. For the cost of doing it now, you'll regret not doing in future when you decide to wire a valve in, but can't dig your floor up :-)

Having the rads and the UFH on the same run is fine, because you would use the 3 port mixer to blend some of the cooler return water from the UFH back into the feed for the UFH, so that the UFH runs cooler than the rads. That's the normal way of doing things anyway.

thanks again @beardymarrow! Does the valve go the heat pump end with the actualor? I will run the wires anyway in now and then worry about it when we replace the ground source with an air source one day in the not too distant future

beardymarrow

Hi,
It goes on the UFH feed pipe after it has Tee'd off from the rad feed and connects the UFH feed and returns together. The actuator sits on the valve, to motorise the otherwise manual valve. The valve and actuator are Q41 on this diagram (from Page 55 of the manual) and the temperature sensor for the UFH is T4.

Strummer22

Our GSHP was installed last year and the installer gave us the first annual service free. I’ve been advised that future services will cost £250 each (I’ve not signed up to a service plan or anything, it would be PAYG). Does that sound reasonable to service a GSHP? 

I need to check whether an annual service is required for the warranty to be valid, if not then will it be ok to service it less frequently?

DeeWestern

I need to check whether an annual service is required for the warranty to be valid, if not then will it be ok to service it less frequently?

The feeling here is that a service is a waste of time, Grumbler likes to ask how often you get your fridge (that works pretty much the same way) serviced!

I do have some issues now and again with the pressure vessels losing pressure, but had no biggies other than some blocked pipes in the last 10/15 years - and the cost of this fix was about the same as one of your annual services. 

However, last month my compressor went completely kaput - burnt itself out, got too hot and caused wires to short. I'm not sure a service would have detected this beforehand? But it could have had a much nastier outcome...



Got a new compressor and soft-start, and had them installed for about £4k






The trouble is that heat pump engineers are few and far between, and don't take total ownership of issues! They fitted it whilst I was out, and said they saw the water tank go up 8 degrees before leaving.

But I'm still having lots of issues - the inside of the heat pump box is much hotter than it's been before, and giving regular High Pressure Switch and Electrical Cassette errors. 

It's trying and trying to heat up the hot water, and whilst it's generating enough for showers etc., the reported temperature from GT3 is around 23 degrees. The flow from the heatpump is v hot, and returning OK from the water tank - GT8 about 58, GT9 about 50. GT6 heats up steadily over about 7 minutes to 83 degrees, when the heat pump turns off (due to GT8 I think, but doesn't alarm).

After a while (anywhere from 20 minutes to a couple of hours) I get either the HP or EK or both errors.

As the hot water isn't getting hot enough, I'm not getting any heating. 

GT3 probe is working fine - I've tested it in some hot water and it's reporting OK, and I've adjusted it so it's 2/3rds of the way down the tank rather than at the very bottom.

The compressor is making lots of new noises compared to the old one... not sure if the old one (which was like a solid hum) was wrong, or the new one is, but it's definitely not consistent. The new one sounds a bit like a kettle when in operation, and when it stops there's some whistling.

I'm a bit worried about it, so I enabled 5.4 ("only additional heat"), but got a HP error that I can acknowledge but not instantly clear. I've put the GT3 probe in some hot water now, and the heating runs OK - it doesn't get so hot in the heat pump, and doesn't seem to be alarming, and the compressor sounds normal. I can't work out why the water tank isn't getting hotter at the bottom of the tank than 23 degrees, maybe it just needs to run longer, but it's alarming before it can get there. Could the heat exchanger around the water tank get sludged up?

If anyone has any thoughts, let me know. The compressor installers think it might be desperate for a flush (as my heating is pretty dirty) and advised if "dirt has clogged the condenser ( plate heatex ) then this will be very challenging to remove" but I'm not sure this is just the only problem I have! 

Here's the new compressor in action with the kettle noise: https://www.tiktok.com/@ohmss007/video/7238193899469016346?lang=en

Here's the new compressor stopping with the whistling noise: https://www.tiktok.com/@ohmss007/video/7238194064594619675?lang=en

Are these noises OK?

DeeWestern

Spent some more time diagnosing, as everything just got hotter and hotter other than the hot water itself! The water tank had a Worcester white container with a front that has never come off, it had been bodged on by the installer - but I attacked it with a spanner and got it off - the problem was clear!

Someone had taken out the GT3 probe, which dangled down through a hole in the top of the outer white container of the hot water tank. They they then put it back down the hole... but inadvertently put it on the outside of the insulation, rather than the inside. So the hot water was super hot, and the return to the GSHP was hot, but GT3 returned a low value. I've tucked it in to the insulation now, so hopefully the GSHP will run smoothly now its not being overtaxed.

Got the cover off!


Tucked the GT3 probe in:

Strummer22

Hope you’ve fixed the problem!
 

My GSHP is literally a box with pipes going in and out. I wouldn’t know where to start if I had a problem like that!

DeeWestern

That's where I was a decade ago before reading this thread! I'd suggest doing what you need to keep the warranty valid, but no more.