Hi folks, hopefully someone can help as this problem is doing my head in. Sorry for the long story but just want to fill in on what’s going on.
Father in-laws boiler was dropping pressure with no sign of leaks on system. I checked expansion vessel and it had lost charge so must’ve been discharging through pressure relief, so re-pressurised vessel to 0.75bar as stated on the vessel.
1 week later pressure had dropped again so put balloon over pressure relief pipe and after 7 days it’s had dropped and balloon was full. I checked exp vessel again and was fine so replaced pressure relief valve thinking it maybe wasn’t closing down properly due to running for a while. I also emptied balloon and refitted it.
After a few days pressure dropped to zero again and the balloon was full....again. The pressure in the system never got above 1.5bar and that was running it on service mode for around 30mins and the relief valve is set to go at 3bar. Also temperature never goes above 70*c.
I assumed it was a faulty relief valve so ordered a new one and fitted it. Emptied balloon and re-fitted it.
A week passes with new valve on and pressure drops again with balloon full again.
Im checking exp vessel when system is empty and drain valves are open and I’m using genuine Vaillant parts. Surely I can’t be unlucky enough to get 2 faulty valves? Am I missing something? Any help would be appreciated. Thanks
Father in-laws boiler was dropping pressure with no sign of leaks on system. I checked expansion vessel and it had lost charge so must’ve been discharging through pressure relief, so re-pressurised vessel to 0.75bar as stated on the vessel.
1 week later pressure had dropped again so put balloon over pressure relief pipe and after 7 days it’s had dropped and balloon was full. I checked exp vessel again and was fine so replaced pressure relief valve thinking it maybe wasn’t closing down properly due to running for a while. I also emptied balloon and refitted it.
After a few days pressure dropped to zero again and the balloon was full....again. The pressure in the system never got above 1.5bar and that was running it on service mode for around 30mins and the relief valve is set to go at 3bar. Also temperature never goes above 70*c.
I assumed it was a faulty relief valve so ordered a new one and fitted it. Emptied balloon and re-fitted it.
A week passes with new valve on and pressure drops again with balloon full again.
Im checking exp vessel when system is empty and drain valves are open and I’m using genuine Vaillant parts. Surely I can’t be unlucky enough to get 2 faulty valves? Am I missing something? Any help would be appreciated. Thanks
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