I've drained the system this weekend to move taps and radiators and I've bled the system but I get no flow on the hot water when running hot water. The water just runs cold, I've checked for voltage across the flow wires but there isn't even when running hot water. Could it be the flow switch?
Grant combi 21e no flow on hot water
- Thread starter coopersim
- Start date
If the burner fires when you turn the tap the flow switch is fine.
If the burner is firing but you have no hot water more likely diverter valve
is sending the heat into the central heating.
If the burner is firing but you have no hot water more likely diverter valve
is sending the heat into the central heating.
The flow light doesn't come on when the hot water is turned on, neither does the burner and there is no power through the flow switch when the hot water tap is on, but I'm wondering if I have an air lock possibly?
If you have power to one side of the flow switch but not to the other
it is the flow switch.
You should be able to bridge the contacts were the flow switch is connected and the boiler will fire up to supply hot water.
Disconnect flow switch. The flow switches are usually fairly basic it might just
need dismantling and cleaning out. They are usually just a paddle.
You can then test it to see if it conducts when you move the paddle.
it is the flow switch.
You should be able to bridge the contacts were the flow switch is connected and the boiler will fire up to supply hot water.
Disconnect flow switch. The flow switches are usually fairly basic it might just
need dismantling and cleaning out. They are usually just a paddle.
You can then test it to see if it conducts when you move the paddle.
Many thanks.
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