Hi, some desperate assistance required please. So, recently come to address an issue where the Vaillant Boiler 837 has had isolating valves fitted, since then, when DHW is used, the boiler pressure drops, as if the water that holds the pressure is released in hot water.
also, when I turn the boiler turn on from off position, it has the flame symbol, Bar, Temperature, Egg timer, C, arrow up and Heating symbol. I cannot find a way to turn on the hot water symbol on the boiler, nor does it work. It has has a recent replacement of PCB board.
When I press 2 buttons + and -, the radiators heats up within minutes. The boiler was reset to factory reset and D0 menu has been set to max output.
also D.23 is set to Winter settings.
I set the wire between terminal 3 and 4 which would not use my room thermostat, it did not do anything when I left it powered on for over 2 hours. Then I removed the wire between terminals 3 and 4, instead used the cable coming from Thermostat to terminals 4 (brown) and 5 (Blue), thermostat was set for 30 Degrees and no action once the boiler was turned on. No Fault codes are present. just SF.H is present when I press the plus and minus symbols to get the heating working.
For info:
Rads have been checked and have been blead. CH flow from boiler is hot, CH return is warm, I have 4 radiators, and when the heating works, they are all hot.
Any assistance is much appreciated.
also, when I turn the boiler turn on from off position, it has the flame symbol, Bar, Temperature, Egg timer, C, arrow up and Heating symbol. I cannot find a way to turn on the hot water symbol on the boiler, nor does it work. It has has a recent replacement of PCB board.
When I press 2 buttons + and -, the radiators heats up within minutes. The boiler was reset to factory reset and D0 menu has been set to max output.
also D.23 is set to Winter settings.
I set the wire between terminal 3 and 4 which would not use my room thermostat, it did not do anything when I left it powered on for over 2 hours. Then I removed the wire between terminals 3 and 4, instead used the cable coming from Thermostat to terminals 4 (brown) and 5 (Blue), thermostat was set for 30 Degrees and no action once the boiler was turned on. No Fault codes are present. just SF.H is present when I press the plus and minus symbols to get the heating working.
For info:
Rads have been checked and have been blead. CH flow from boiler is hot, CH return is warm, I have 4 radiators, and when the heating works, they are all hot.
Any assistance is much appreciated.
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