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canuck the pro
canuck the pro, Plumber
Category: Appliance
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Experience:  Plumber
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Hi, I have a glow worm boiler installed 2 years back all worked

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Hi, I have a glow worm boiler installed 2 years back all worked fine, except that I've just noticed that the pressure whist nothing is on drops to 0.4 bar and flashes. I mean it's on a timer and heating works so does the hot water.
I'm not sure as to what the issue could be, as mentioned the heating comes on and the pressure is fine. Also the hot water is fine.
Checked for leeks in the boiler and all the rads but nothing.
What could cause this? Should I get a glow worm tech out to come and check it out?
The model is a betacom 24

Hi, my name is ***** ***** I have been in the home improvement and repair field for 20 years. I will be very glad to help you today. The thermal expansion will cause some drop in pressure along with there may be a small leak that is yet undetected. If the pressure does drop any further the system can be topped up as needed. It is not unusual for a system to lose a bit of pressure with time and it could have not been overly pressured upon installation. The minimum operating pressure is 0.5 bar so it does seem that it is at minimum which is fine.

JACUSTOMER-qbyk2m0l- : The 0.4 bar only occurs when the boiler is idle, I mean the heating works and so is the HW. Question is should I be concerned and will this cause damage of any sort?
JACUSTOMER-qbyk2m0l- : When I look at the booklet provided by the makers glow worm it says that if the pressure drops to 0.4 bar there could be a lack of water in the system and

It will not cause any damage. No reason to be concerned. It will not hurt to monitor if the pressure does drop then the heating may go out until the pressure is added again. Otherwise no worries and if the pressure does not drop then no reason to do anything and all will work fine as usual.

JACUSTOMER-qbyk2m0l- : Apologies Mike I pressed the "send" without finishing what I wanted to say. So the booklet from the manufacture says that if the pressure drops to 0.4 bar could be a lack of water, but with both HW and CH working I'm not sure that it applies to my boiler. Everything seems to work but I'm not an expert and clearly I never noticed this happening before so hence the concern

You are operating now near the minimum operating pressure which is very good. There will be no issues unless you have been losing pressure. It sounds to me that is the operating pressure you have had ever since the installation. Worst case scenario is that you have to add pressure at some point. Very doubtful that you will and no damage will occur from having to top up the pressure at some point.

JACUSTOMER-qbyk2m0l- : Super thx for the clarification its a mind field when it comes to boilers and pressures he he
canuck the pro and other Appliance Specialists are ready to help you

You are very welcome.