I have a Warmflow combi fitted and it's never really worked correctly.
One problem that's been very difficult to isolate seems a little clearer now but is still causing the plumbers problems to isolate the fault.
We have a standard external dual timer fitted.
Symptoms:
During the summer the boiler *overheat* kept tripping and had to be reset.
Seemingly intermittently, or when certain conditions occur, the heating stops working for hours at a time.
(Possibly unrelated) When calling for DHW there is a 20 second delay where cold water is drawn through the boiler before the DHW supply pipe begins to heat (unless within 30sec-1min of the last time DHW used). This means that at the taps you have the run off of warm water, then 20sec of cold before any hot comes through from the boiler.
What appears to be happening:
We've managed to narrow this down to what, I think, is a definite fault. When the heating does not come back on, or has not fired for a while, I find that the boiler is in pump over run mode but is pumping the water around the DHW circuit, i.e. it is pumping it around the boiler, through the heat exchanger. The heat is not being dissipated but remains in the boiler and the return pipe into the *main boiler* is as piping hot as the send.
If I switch the DHW off at the external timer then the boiler immediately switches back to the heating circuit and works correctly again. If the house is cold then the heating comes back on, if not then the pump over run continues normally and return pipe drops in temperature as it should as the heat is being dissipated outside the boiler. With the DHW back on and the pump over run goes back to pumping the water around the boiler and through the heat exchanger.
Warmflow want to speak to the plumber when he is on site, but there is often a queue at their call centre and especially at this time of year they simply don't have the time to wait around. So it is proving very challenging for me as a homeowner to get this diagnosed and corrected. At present Warmflow have resorted to their standard *most likely and see* part replacement and have indicated that the pump over run state should be replaced. But it's possible that the reason the boiler gets stuck in pump over run is because the thermosistor is working correctly and the heat is simply not being dissipated because it's continually pumping it around the boiler instead of round the heating pipes.
We have checked the wiring for the external timer and substituted it for a known working one, the wiring is as described in the boiler manual and the fault remains unchanged.
Hoping that someone understands and has seen a similar fault.
One problem that's been very difficult to isolate seems a little clearer now but is still causing the plumbers problems to isolate the fault.
We have a standard external dual timer fitted.
Symptoms:
During the summer the boiler *overheat* kept tripping and had to be reset.
Seemingly intermittently, or when certain conditions occur, the heating stops working for hours at a time.
(Possibly unrelated) When calling for DHW there is a 20 second delay where cold water is drawn through the boiler before the DHW supply pipe begins to heat (unless within 30sec-1min of the last time DHW used). This means that at the taps you have the run off of warm water, then 20sec of cold before any hot comes through from the boiler.
What appears to be happening:
We've managed to narrow this down to what, I think, is a definite fault. When the heating does not come back on, or has not fired for a while, I find that the boiler is in pump over run mode but is pumping the water around the DHW circuit, i.e. it is pumping it around the boiler, through the heat exchanger. The heat is not being dissipated but remains in the boiler and the return pipe into the *main boiler* is as piping hot as the send.
If I switch the DHW off at the external timer then the boiler immediately switches back to the heating circuit and works correctly again. If the house is cold then the heating comes back on, if not then the pump over run continues normally and return pipe drops in temperature as it should as the heat is being dissipated outside the boiler. With the DHW back on and the pump over run goes back to pumping the water around the boiler and through the heat exchanger.
Warmflow want to speak to the plumber when he is on site, but there is often a queue at their call centre and especially at this time of year they simply don't have the time to wait around. So it is proving very challenging for me as a homeowner to get this diagnosed and corrected. At present Warmflow have resorted to their standard *most likely and see* part replacement and have indicated that the pump over run state should be replaced. But it's possible that the reason the boiler gets stuck in pump over run is because the thermosistor is working correctly and the heat is simply not being dissipated because it's continually pumping it around the boiler instead of round the heating pipes.
We have checked the wiring for the external timer and substituted it for a known working one, the wiring is as described in the boiler manual and the fault remains unchanged.
Hoping that someone understands and has seen a similar fault.
