Ground Source Heat Pumps

lovesgshp

Will check for the part numbers. You should be able to replace yourself, or use a plumber. just remember to air bleed after the check or change if needed.

Have you the model and serial number of the pump and date of manufacture? Should be on a sticker on the top.

lovesgshp

This place may be worth a look. I could not see the pipes, but they do have a online help service if you need to check.

https://www.ivtspares.co.uk/collections/popular-items

lovesgshp

DeeWestern said:

lovesgshp said:

That is great news. So pleased everything is working even if only a temporary repair at the moment. The units are fairly straightforward to diagnose, which is why I was confused with the answers from the first 2 electricians.

Hope you had a good Easter and now a little more relaxed

I am warmer at least, and can have a shower.
Electrician said there was a MCB behind the RCB which showed signs of burning, and a disconnected wire. The MCB still works, but will be replaced in a few days.

The 8/9 alarm triggered almost immediately, when it was getting the hot water up to temp. This means it can't be anything to do with the central heating pump or radiators.
The only possibility I can see (as the 3 way valve is working great, (You have checked that on the I/S manual operation?) and removing the filter doesn't prevent the alarm) is that the flexible hoses are somehow blocked (which seems strange as they're metal) or the main pump just runs slow for some reason. "" Check the circulating pump from manual operation of all settings and to make sure there is no airlock by unscrewing the front valve, while not running""
I might one day take the hoses off and look inside - I guess I only need a spanner and some PTFE tape? Worried I cause a leak, as it works fine (other than the beeping of course) and I can't see how a metal flexible hose gets a blockage. Or maybe I should get the whole thing serviced, no-one has looked at it for 5 years - is there much maintenance to do?

There is virtually no maintenance to do on these units and no annual service by anyone else really needed.

You check the filters once a year, unless it is a new install. Check refrigerant for bubbles which normally disappear after about 30 secs from startup. Check pressures on circuits on operating (0.5 on ground loops , 1.5 on heating circuit).

Just look at the alarm panel warnings, as there could be some that show but reset automatically. Trying to help remotely from 1000+ miles away is difficult, but is not like I can stand in front and try to work out the problem, which is why I ask so many questions.

Think of how many times you have to call your refrigerator engineer out, as the unit is just working in reverse in a heat pump.

Having had one of these type of units for about 15 years now, that is what I look at, so 1 hour approx in total, far less than boiler certification and far cheaper. You have no real risk of fire or being gassed from fumes, or having to carry logs around. I still have about 3000 k of logs we bought about 15 years ago, just in case of power cuts, but with about 2-3 fires a year, they will well last me out, plus no real pollution.

I love the constant temp from the underfloor heating and constant hot water, so thats life here in Italy at the moment.

ARtYXiFy

DeeWestern,
Your analysis is quite right, there is a problem with the flexible hoses that go to and from the heat exchange unit. Although they are flexible and have a rubber insert they also have a stainless steel covering both internally and externally and are therefore ferromagnetic. These hoses act as a beautiful magnetite trap and over the years will have gradually occluded and now the flow through them will be really quite reduced.This is the engineering equivalent of human angina. Put a magnet on them to prove it to yourself.
This firm can supply replacement hoses.           jsenergi.co.uk 
Type in these search terms:

Slang¾ LöpMutt90 ° ¾ LöpMutt¾

and

Slang¾ utv¾ löpmutt¾

Personally I had a plumber do the job, though you may be very capable. It will recur but many years away hopefully. You could try putting a magnetic filter in, flush the system and refill with inhibitor. G8/G9 (the Delta) should now drop back into the acceptable range of 7-10 degrees.

ARtYXiFy

Just a bit more 'opinion' on this. These systems work without trouble for many as 'lovesgshp' testifies. The major issue I would guess is those sytems which have been retrofitted to existing heating systems with years of magnetite and other crud built up in radiators. The saving grace for the heat pumps is that the heat exchange unit does not attract megentite so either cleaning out or replacing the in/out flexible hoses corrects the problem for a while. I would guess that these systems work near faultlessly when only warming underfloor systems. My system (2009 Ice Energy) has this problem every few years and I get the things either cleaned or more recrntly replaced. It is a major issue with retrofits and I discovered even mentioned  in the IVT handbook:
to my mind this has been a big problem bringing this technology into the UK and should have been avoided but what do I know?

poohbear59

Hi, I have a gshp in my cottage that I let to holidaymakers. I left the pump on so it heats the water but turned off the heating. The cottage has been empty since early March and I am very aware that we need to be careful about Legionnaire's disease. How do I check that the temperature is above 50C?
Anything else I need to be aware of? I have some people going in there to work later this week and I want it to be safe.

beardymarrow

poohbear59 said:

Hi, I have a gshp in my cottage that I let to holidaymakers. I left the pump on so it heats the water but turned off the heating. The cottage has been empty since early March and I am very aware that we need to be careful about Legionnaire's disease. How do I check that the temperature is above 50C?
Anything else I need to be aware of? I have some people going in there to work later this week and I want it to be safe.

Hi Pooh,
You can check it from the front panel. Assuming you have an IVT Greenline/Bosch equivalent Press menu, then scroll to 3 (Monitor all Temperatures), select that and then scroll to Temperature readings Hot water (see picture below for page from the manual). I don't think 50C is high enough to kill legionella though? Anyway, that I'll leave to you :-)

poohbear59

Thank you. I do have same gshp as you and have now found the correct settings. I'll set the temperature higher than 50C to be on the safe side. 

poohbear59

I wouldn't be trusted. I found the instructions and went into customer level 2. I wanted to change the add extra heat day to today and increase the temperature on the water. I wasn't sure what the add heat was so increased it to 4 hours, then read the instructions and turned it back to zero.  The pump went off. And I now have a display that says this..... How do I change this so we get hot water please? Or have I damaged something?

beardymarrow

You've not broken anything, don't worry, that just means there is no demand for hot water at the moment, because the hot water temp is already above the setting.

The "extra hot water" setting is a duration whereby the heat pump will increase the temp of the water, for example if you've got a lot of guests staying at your house and might need more hot water than normal.
To increase the hot water temp periodically (to kill legionella etc) you want to change the "Hot water peak" (Customer Level 2, Menu Item 2 and then "Interval for Hot Water Peak" . On some systems, depending on the age of your control unit you can set that to None, Every Day, or a specific day of the week. you might also be able to set if it does it every week, every 2 weeks etc. what time of day it does it and how long to keep it at peak. On mine I just get "Interval for Hot Water Peak" which I'd set to 7 days to do it once a week. I think it then does it every 7 days from the day you set it you can't chose what day of the week that is.

Quote from the manual :- 

"Hot water peak

Recurring increase in the hot water temperature

In the menu Interval for hot water peak is used to set the interval for recurring increases in the hot water temperature. When you state the value seven days, for example, the temperature is increased by a further 5 degrees once a week."
Manual and Hot Water Peak info attached.