Ground Source Heat Pumps

howardht

Hi lovesgshp

Much appreciate your response. By the way I think I mislead you re valves prior to the manifold. They ARE there. One for each of the two circuits on the inflow and the same on the outflow.

I also understand what you say about involving IE to do the pressure test. This morning I bypassed their technical dept and spoke to their customer services people and they agreed to send out an engineer to do the test and do a diagnosis of what may be going on. They will do this as a service to me as a customer, but should any repair be required, I will have to bear any groundwork and other repair costs. (At some point firms like IE need to sort out a one stop guarantee for customers if they want to spread the use of this technology. It's not knowing what you are liable for and the potential cost/disruption that which is causing my stress!)

I'll get back to you tomorrow when the engineer has been.

all the best
howardht

lovesgshp

Hi Howardht.

Glad they are sending out a techie so quickly. If he does the pressure test, make sure the pressure holds for at least 20 mins on each circuit. We use around 2-3 bar normally.
I must admit that for a unit that has been installed for such a short time, then the collectors should still be under warranty for leaks. It may be something to do with you as not the previous owner, that the guarantee is not transferred.
Best of luck for tomorrow.

Patrol

Hi
Pressure gauges on the ground loop were never mentioned as part of my install.

My plumber pressure tested, although he did check with the supplier because they stated a liquid test and he opted for a gas (air?) test.

Hope it goes well for you tomorrow, uncovering collectors doesn't sound like fun even if your ground isn't waterlogged (my trenches backfilled fairly quickly but on the positive side that is meant to help efficiency-wise).

Oh, and my figures. Beardy, how is your use faring.
Pump 14146 (+111 since 23 May). Similar to lowest years recorded.
Cassette 906 (+2 since 23 May). Would normally be 10-15 hours.

howardht

Hi Guys

I have just written you a detailed report on the IE engineer's visit and it seems that it didn't post! I can't face doing it all again, so here is a quick summary.

The fault appears to have been in the manifold area in a joint belong the 4 circuit joints. The give away was the acrid smell of stale glycol accumulated at the bottom of the inspection pit. (I had always suspected as much but the builder felt that it was just stagnant water.) He first replaced all the circuit joints, pressurised the system, and then noticed air bubbles in the water next to one of the pipes. The joint above it was loose which he then reconnected properly. When the system was repressurised, the bubbles had gone, the water was still and the pressure held up. It was tested for at least 30 mins per circuit, and monitored for another 35 mins with both circuits open (all tests at 3 bar).

While he was here, he replaced the expansion bottle as it had developed a hairline fracture, and cleaned both filters (glycol inflow and water outflow). He was very thorough and knowledgeable, and spent the whole day here making sure that everything was ok.

So I am very pleased with the result so far. He could not guarantee that there weren't any more leaks underground, but he is 90%+ sure that he has found the problem (and so am I).

So full marks IE for some excellent aftersales support several years after installation.

I have to monitor the expansion bottle and get back to IE with anything that still occur.

Many thanks to all of you, lovesgshp (a real expert!), beardy and patrol for you radvice and support. I'll keep in touch.

Cheers
howardht

lovesgshp

Great news Howardht and fingers crossed that the problem is now resolved. IE have done a good job with the quick response and finding the source of the problem, plus spending the best part of a day there.
Now hopefully you can sleep at night!!!!

lovesgshp

Patrol wrote: »

Hi
Pressure gauges on the ground loop were never mentioned as part of my install.

My plumber pressure tested, although he did check with the supplier because they stated a liquid test and he opted for a gas (air?) test.

Hope it goes well for you tomorrow, uncovering collectors doesn't sound like fun even if your ground isn't waterlogged (my trenches backfilled fairly quickly but on the positive side that is meant to help efficiency-wise).

Oh, and my figures. Beardy, how is your use faring.
Pump 14146 (+111 since 23 May). Similar to lowest years recorded.
Cassette 906 (+2 since 23 May). Would normally be 10-15 hours.

Hi Patrol.

The figures on the running hours are looking good. If you need to, you can cut the electric cassette off altogether, or reduce it to 1/3, but that is up to you.
With regard to the loop pressure valve, then I would recommend it, with a mains connection. It is a visual guide that lets you know the pressure in the loop that you can increase or decrease as needed.

tinkytonkytank

We have a borehole which we draw approx 10 cubic meter per day from - would it be worth running that through a heat exchanger before it is used for drinking/irrigation?

lovesgshp

tinkytonkytank wrote: »

We have a borehole which we draw approx 10 cubic meter per day from - would it be worth running that through a heat exchanger before it is used for drinking/irrigation?

If you are talking of a open loop system then you should not think of using the water for drinking. A normal open loop will discharge to a alternative site.

Suggest you look at this information as regs vary between countries:

http://www.gshp.org.uk/pdf/EA_GSHC_Good_Practice_Guide.pdf

beardymarrow

Patrol wrote: »

<snip>

Oh, and my figures. Beardy, how is your use faring.
Pump 14146 (+111 since 23 May). Similar to lowest years recorded.
Cassette 906 (+2 since 23 May). Would normally be 10-15 hours.

Hi Patrol,
Sorry it's taken so long to reply
Pump +279 since 2 May, so average 2Hrs per day
Add Heat +2 since 2 May and both of those were when I was messing with the DHW pasteurisation cycle.

Better than the 15Hrs per day of pump usage I was getting

Beardy

Xander_Sim

HowardHT many thanks for the posts I have experienced the exact same with a skewed Plasson fitting on one of the joints to a collector.
I've been losing less fluid than you but still losing a pint a month.
Hopefully after today's repair this will have sorted it.
Thanks again to you and the other gurus!
Xander