If the pilot flame is not strong enough, it will not tell the gas valve to open, or if the gas valve is not getting the signal to open, it won't. Check all wire connections at the thermostat and gas valve. Check ground wires. Clean the pilot light and flame rod.
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Ive got the same problem and am fitting a new thermal generator i will let you know if it works
If the pilot flame is not strong enough, it will not tell the gas valve to open, or if the gas valve is not getting the signal to open, it won't. Check all wire connections at the thermostat and gas valve. Check ground wires. Clean the pilot light and flame rod.