Hi,
yesterday I attempted to replaced my existing LightwaveRF thermostat and boiler switch with a new Honeywell Evohome system, but I'm having problems with it. The boiler is a Vaillant ecotec plus 831 Combi Boiler.
I believe the boiler switch is wired up correctly (though I may be wrong!), if I press the switch on it to turn it on manually then the green light comes on and the boiler seems to fire up and run OK but it only stays on for a few minutes (the actual length of time seems a bit random but don't think it's run for longer than ten minutes) and then it switches off, green light goes off and the boiler shuts down (though the pump keeps on running for a few minutes I think). This behaviour is the same whether the thermostat itself is powered or not.
The thermostat seems to be connected to the switch OK and testing reports a good signal, but it never seems to turn the boiler on, even though the current temperature is below the target, not currently using any TRVs (that's another issue!) just relying on the main thermostat as the temperature sensor.
So, any suggestions for what the problem might be? Could something wrong in the wiring cause that behaviour? That seems unlikely as the switch seems to correctly run the boiler, it's just that the switch itself doesn't come on and stay on like it should but I'm certainly no expert.
edit - Oh, and hot water from the boiler seems to be working OK.
yesterday I attempted to replaced my existing LightwaveRF thermostat and boiler switch with a new Honeywell Evohome system, but I'm having problems with it. The boiler is a Vaillant ecotec plus 831 Combi Boiler.
I believe the boiler switch is wired up correctly (though I may be wrong!), if I press the switch on it to turn it on manually then the green light comes on and the boiler seems to fire up and run OK but it only stays on for a few minutes (the actual length of time seems a bit random but don't think it's run for longer than ten minutes) and then it switches off, green light goes off and the boiler shuts down (though the pump keeps on running for a few minutes I think). This behaviour is the same whether the thermostat itself is powered or not.
The thermostat seems to be connected to the switch OK and testing reports a good signal, but it never seems to turn the boiler on, even though the current temperature is below the target, not currently using any TRVs (that's another issue!) just relying on the main thermostat as the temperature sensor.
So, any suggestions for what the problem might be? Could something wrong in the wiring cause that behaviour? That seems unlikely as the switch seems to correctly run the boiler, it's just that the switch itself doesn't come on and stay on like it should but I'm certainly no expert.
edit - Oh, and hot water from the boiler seems to be working OK.
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