• Welcome to PlumbersForums.net - The international free plumbing advice forum. Professional plumbers sharing advice with fellow plumbers and DIY alike. Register for free today! - Checkout the Plumbing Advice forum and then our Plumbing Videos area which still needs populating.

Discuss Gledhill Unvented Cylinder Loud Bang Hot Water Demand in the Plumbing Forum | Plumbing Advice area at PlumbersForums.net

Messages
3
Recently had a new heating and hot water system retrofitted in a domestic property. Previous hot water system was gravity fed with a vented cylinder. New system as shown in the photos. Installer commissioned system about 3 months ago and all was working fine.

There have since been two faults:

1.) About 6 weeks ago the pressure relief pipe came off inside boiler, large amount of water leaked from the boiler, cause was a faulty thermostat on the Gledhill cylinder. Damage caused to boiler as PCB was beyond repair.
2.) Within the past 4 weeks the Gledhill cylinder has developed a popping sound whenever there is demand for hot water. This has now got to a volume that is alarming if standing near the cylinder. I've attached a video of this happening.

Could an experienced and G3 registered plumber provide opinion on the overall installation as shown in the pictures - do we have a sound installation or are there signs of a sub-standard job? I would also appreciate any thoughts on what could be causing the loud popping sound coming from the cylinder.

Any comments gratefully received.
 

Attachments

  • 20210617_190354.jpg
    20210617_190354.jpg
    426 KB · Views: 26
  • 20210617_190455.jpg
    20210617_190455.jpg
    461.3 KB · Views: 24
  • 20210617_190522.jpg
    20210617_190522.jpg
    466.9 KB · Views: 24
  • 20210616_062731_1_convert.mp4
    3.1 MB · Views: 7
Last edited:

scott_d

Plumber
Gas Engineer
Messages
5,664
Have you asked the installer to check it over?
If the secondary hot return is a long run the expansion may be undersized
 
Messages
3
Installer has been asked to check it over however has yet to come on-site, his current thinking is back pressure through a mixer tap which requires a pressure reducing valve fitted above the stock cock or a check valve on the offending hot pipe.
 

scott_d

Plumber
Gas Engineer
Messages
5,664
Could be a few different things.
Best to get the installer out. If they won’t/can’t find the cause you may have to pay another installer or call in the manufacturer
 

Reply to Gledhill Unvented Cylinder Loud Bang Hot Water Demand in the Plumbing Forum | Plumbing Advice area at PlumbersForums.net

Top