I have a Potterton Netaheat Electronic 10/16 gas boiler. When I switch it on the fan starts normally, then the igniter clicks, the pilot lights normally but not the main burner. No matter what setting the thermostat is at it's always the same. Please help as all the gas fitters I have phoned are too busy ( Or don't turn up!) and I'm freezing!

Ian, January 2007

I have a Potterton Netaheat Profile 60e and the gas valve does not open but the pilot works and the fan runs. There appears to be a connection problem on the four wire plug and socket under the boiler. By unplugging and replugging it reseats itself and will then open the valve. A niggling problem especially on a cold morning. Any ideas why the connection is bad?

PottPro60e, November 2008

Sounds like a problem with the flame failure device... Depending on what variant of the 10/16 you have; these can be very hard to come-by - If you can get it at all.

I will suggest that the part you need is a mercury vapour ffd which plugs into the end of the gas valve... As the pilot light (Once lit) heats up the phial, it expands a bellow in the ffd unit, which opens the main gas through into the appliance.

GasAid.co.uk, January 2007