Advice - Gledhill Stainless Lite

[townfanjon]

You really need to know your water pressure .
Personally I wouldn't advise gauges , test point maybe .
As for the engineer who didnt check the vessel, I am lost for words , its the first thing to check . The fact it was only fitted 2 months ago makes no difference, was it set then ?

 

[RickyPB]

Hi,

Did you get this sorted in the end? I have exactly the same issue and it would be good to know what you found.

 

[Stigster]

Before we go wild thinking of everything under the sun that could be at fault here, the symptoms the OP has described would indicate a debris-filled strainer in the group inlet, or a faulty pressure reducing cartridge in the GI.

Pretty much every system I have attended where the pressure/flow rate is blasting out the tap and dying down, it was a partially blocked strainer causing it. Blocked strainers + mains water pressure + pressurised cylinders with expansion vessels = Weird noises and performance issues.

That's the first place a G3 engineer (and G3 they must be!) should look when encountering this symptom. Then have a look at all the other things one would normally do on a service.

 

[IDC]

Before we go wild thinking of everything under the sun that could be at fault here, the symptoms the OP has described would indicate a debris-filled strainer in the group inlet.

Pretty much every system I have attended where the pressure/flow rate is blasting out the tap and dying down, it was a partially blocked strainer causing it.

That's the first place a G3 engineer (and G3 they must be!) should look when encountering this symptom. Then have a look at all the other things one would normally do on a service.

Thanks for the suggestion. The group inlet was only changed a couple of months ago, but will get that looked at.

 

[Dan]

Hi all,

Looking for some advice as a previous posting suggested there are some people quite experienced with Gledhill system on the forum.

I'm having an issue whereby when the hot water has been on and any hot water tap/shower outlet is opened, the hot water pressure is significantly higher than usual. It then returns to normal after a few seconds. If however, the tap/shower is turned on full to the hot, there is a loud vibration and pipe rattling in the area where the cylinder is housed.

(Please upload the video directly to the post rather than linking elsewhere - the content will one day be erased and we are left with a broken post link then)

Once the pressure has returned to normal through opening a hot water outlet, this issue will not occur again until the hot water has been on again. The cold water pressure is totally unaffected and does not cause the vibration/high pressure when in use on any occasion.

There is no water dripping through the Tundish.

The PRV and expansion vessel have both been replaced earlier in the year and have been verified by the engineer as being installed correctly and the PRV is the correct rating.

The Geldhill engineer who visited today recommended that we change our expansion vessel to a 25 litre capacity, from the current 18. Having looked at the manual, it appears that the recommended size expansion vessel for this system is 18 litres. At the time, the engineer inferred that the vessel fitted was the incorrect size, however, the manual seems to suggest this is not the case.

I've had a number of different people (G3 certified) look at this issue and no one can pinpoint the source of the problem (hence why turning to Gledhill directly).

A previous engineer suggested that it is common to have to put the expansion vessel on its side to prevent/limit virbations/noises, however, due to area where the cylinder is housed, this isn't an option unfortunately.

Another has suggested cold water backfilling the system could be the issue, however, I would assume this would mean this vibration/noise would happen far more frequently.

Keen to see if any has experienced similar issues and can shed some light on whether the suggestion of a larger vessel is really going to help?

Obvious caveat, I'm not working on any of this myself!

Thanks

I've moved this thread to the normal UK plumbing forum. And also removed the link to the video. Rather than doing that, in future just click the Add Video button in the post and add it directly to the forum. That saves us having a broken link come next month when you've cleared out your Google Drive clutter.