I wanted to start a new more dedicated thread as I am on about 3 just now in one way or another trying to get up to speed with my problem. The issue is that my Gledhill Stainless Lite indirect unvented cylinder makes loud noises when heating - this is a bit random, but that noise is loud enough to startle and sounds like a mix of a metallic / plastic bang. The noise seems to occur more often when the hot water has been drawn down a bit and is then re-heating but I am not 100% on this. There isnt any noise when hot water is drawing, thought in occasion there is a little bit after a shower, but he noise seems different, like a valve type noise - and it doesnt occur right away after the shower - can be minutes or hours.
My cylinder was installed by BG as a replacement for an old Premier Santon than started leaking last Feb. Cold supplies to taps and shower are off mains, not balanced cold on cylinder with hot from cylinder. Taps are mixer type through the house. One shower is a mixer shower in ensuite. (I think there was a similar set up on the Santon but am not sure.)
Late summer we reconfigured the ensuite - replaced old Mira mixer shower (was a plastic built into wall dial) with a new RAK Thermostatic Mixer. We also replaced the mixer tap (which has separate hot and cold handled) for a single monobloc, single handle mixer tap.
As the work was done we noticed that the mains pressure into the new shower was poor - and the sink/toilet refill wouldnt run at the same time. There were no other issues however and no noise from the cylinder was detected. As a result of work being done I changed the times that the HW was on from mostly during the night, to during the day (this was as the hot water was switched off for a day or so and I just decided to change it after that).
A local plumbing firm checked and there was a stone blocking the valve the stop under the sink. This greatly improved the mains pressure and shower was better, no issues with flush/sink etc. However a few weeks later we started hearing a banging noise when the cylinder was heating up. I couldnt figure out what was going on and neither could BG/Dyno. The noise was very loud. I am not sure if the noise was going on when the HW was running during the night, but I did used to waken up during the night so this may be the case.
This continued for some time until I discovered that the manual bypass was taking most of the water when the HW was on as it was just about fully open. I also discovered that cylinder was never getting up to its target temperature of 60, and when HW was used for showers the cylinder was becoming much colder than this. The banging continued however, usually in about 20-25% of the times the water was heating.
At the annual service for the cylinder I pointed out the issue to the local G3 plumber - the bypass was closed down significantly, and the recovery time of the cylinder improved dramatically, with it able to get to 60 again. The banging got better and less violent but still continued to some extent when heating. I called BG back - they said the bypass was too closed and opened it up a bit (this made the pump overrun at switch off a bit noisier and also got a noisy radiator but am ok with this) There also appears to be a strange noise like a flushing noise coming from the cylinder - usually after it clicks off at temp (or end of the run now) - but the tundish is totally dry and there does not appear to be any water being expelled outside anywhere.
This did not solve the problem, though it was no worse, the cylinder still makes noise when heating - again, it tends to be worse on the cycles after the water has been drawn down a bit.
I am speaking to the manufacturer regarding the noise and will call back BG as and when.
There is a 3bar PRV under the sink(newly fitted when the water pressure issue was resolved) this matches the configuration of the combination outlet on the cylinder. There have always been mixer showers and taps in the house (before and after BG fitted the new cylinder) although there were changed for newer fittings - there has been much debate here about balanced colds and that this is better, but the new cylinder was a retro fit and probably the same as the old Santon with no balanced colds being used.
Can anyone help? I cant work this out - could it be linked to the work we did? Is it down to the cylinder which have had reported issues on them.
I clearly cant add a balanced cold retrospectively (neither did BG obviously) and I cant rip out the ensuite and start again.
I am looking to try and move conversations forward with the suppliers or installers to see what can be done - clearly no one but a G3 will touch anything on the cylinder. I have learned what I can the last few months but am this is not my area at all. If anyone can help me that would be really appreciated as this is incredibly stressful for me, and indirectly, my family.
Thanks in advance.
My cylinder was installed by BG as a replacement for an old Premier Santon than started leaking last Feb. Cold supplies to taps and shower are off mains, not balanced cold on cylinder with hot from cylinder. Taps are mixer type through the house. One shower is a mixer shower in ensuite. (I think there was a similar set up on the Santon but am not sure.)
Late summer we reconfigured the ensuite - replaced old Mira mixer shower (was a plastic built into wall dial) with a new RAK Thermostatic Mixer. We also replaced the mixer tap (which has separate hot and cold handled) for a single monobloc, single handle mixer tap.
As the work was done we noticed that the mains pressure into the new shower was poor - and the sink/toilet refill wouldnt run at the same time. There were no other issues however and no noise from the cylinder was detected. As a result of work being done I changed the times that the HW was on from mostly during the night, to during the day (this was as the hot water was switched off for a day or so and I just decided to change it after that).
A local plumbing firm checked and there was a stone blocking the valve the stop under the sink. This greatly improved the mains pressure and shower was better, no issues with flush/sink etc. However a few weeks later we started hearing a banging noise when the cylinder was heating up. I couldnt figure out what was going on and neither could BG/Dyno. The noise was very loud. I am not sure if the noise was going on when the HW was running during the night, but I did used to waken up during the night so this may be the case.
This continued for some time until I discovered that the manual bypass was taking most of the water when the HW was on as it was just about fully open. I also discovered that cylinder was never getting up to its target temperature of 60, and when HW was used for showers the cylinder was becoming much colder than this. The banging continued however, usually in about 20-25% of the times the water was heating.
At the annual service for the cylinder I pointed out the issue to the local G3 plumber - the bypass was closed down significantly, and the recovery time of the cylinder improved dramatically, with it able to get to 60 again. The banging got better and less violent but still continued to some extent when heating. I called BG back - they said the bypass was too closed and opened it up a bit (this made the pump overrun at switch off a bit noisier and also got a noisy radiator but am ok with this) There also appears to be a strange noise like a flushing noise coming from the cylinder - usually after it clicks off at temp (or end of the run now) - but the tundish is totally dry and there does not appear to be any water being expelled outside anywhere.
This did not solve the problem, though it was no worse, the cylinder still makes noise when heating - again, it tends to be worse on the cycles after the water has been drawn down a bit.
I am speaking to the manufacturer regarding the noise and will call back BG as and when.
There is a 3bar PRV under the sink(newly fitted when the water pressure issue was resolved) this matches the configuration of the combination outlet on the cylinder. There have always been mixer showers and taps in the house (before and after BG fitted the new cylinder) although there were changed for newer fittings - there has been much debate here about balanced colds and that this is better, but the new cylinder was a retro fit and probably the same as the old Santon with no balanced colds being used.
Can anyone help? I cant work this out - could it be linked to the work we did? Is it down to the cylinder which have had reported issues on them.
I clearly cant add a balanced cold retrospectively (neither did BG obviously) and I cant rip out the ensuite and start again.
I am looking to try and move conversations forward with the suppliers or installers to see what can be done - clearly no one but a G3 will touch anything on the cylinder. I have learned what I can the last few months but am this is not my area at all. If anyone can help me that would be really appreciated as this is incredibly stressful for me, and indirectly, my family.
Thanks in advance.
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