Hello DIYNot Community.
We recently replaced an old boiler which occasionally (less than once a month) halted with a fault code related to pressure.
The new boiler, once installed, halts with a code related to the temperature differential between in- and out-flow much more frequently than the older boiler. It can happen three times in a day, or not at all for five days. It happens when the boiler is first heating up from cold - I've noticed that if I reset it straight after it happens the flow temp shoots up to 80s and then drops down to 40s and trickles back up to around 70.
The installers first thought there was an airlock causing the problem, so we had the system (previously open vent) pressurised and bled the radiators routinely, but the problem persisted. They next thought that there was some other blockage, and so we had a "powerflush" of all the radiators. The problem has persisted.
They also inspected the pump, and this seems to be in working order. We also recently replaced the three-port about three years ago, so that doesn't seem to be a likely cause of the problem.
In the meantime, we've had the manufacturer engineers out three times. The last time they replaced the sensors, wiring and PCB. This also didn't stop the faults.
As far as I can see, there is something which intermittently causes the flow of water to be too slow when the boiler first comes on. The installer is now saying the only thing they can think to do next is trace the pipework but it will involve lifting the floorboards and it will be expensive and disruptive.
Is there anything we can do try and diagnose the problem before taking any expensive next steps? We've been trying to figure it out for six months now and we're becoming quite despondent.
Any ideas are greatly appreciated.
The old boiler was a Glow Worm Flexicom 15HXI, the new boiler is a Glow Worm Energy7 18kW heat-only boiler.
We recently replaced an old boiler which occasionally (less than once a month) halted with a fault code related to pressure.
The new boiler, once installed, halts with a code related to the temperature differential between in- and out-flow much more frequently than the older boiler. It can happen three times in a day, or not at all for five days. It happens when the boiler is first heating up from cold - I've noticed that if I reset it straight after it happens the flow temp shoots up to 80s and then drops down to 40s and trickles back up to around 70.
The installers first thought there was an airlock causing the problem, so we had the system (previously open vent) pressurised and bled the radiators routinely, but the problem persisted. They next thought that there was some other blockage, and so we had a "powerflush" of all the radiators. The problem has persisted.
They also inspected the pump, and this seems to be in working order. We also recently replaced the three-port about three years ago, so that doesn't seem to be a likely cause of the problem.
In the meantime, we've had the manufacturer engineers out three times. The last time they replaced the sensors, wiring and PCB. This also didn't stop the faults.
As far as I can see, there is something which intermittently causes the flow of water to be too slow when the boiler first comes on. The installer is now saying the only thing they can think to do next is trace the pipework but it will involve lifting the floorboards and it will be expensive and disruptive.
Is there anything we can do try and diagnose the problem before taking any expensive next steps? We've been trying to figure it out for six months now and we're becoming quite despondent.
Any ideas are greatly appreciated.
The old boiler was a Glow Worm Flexicom 15HXI, the new boiler is a Glow Worm Energy7 18kW heat-only boiler.
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