R
ronrocket
The above boiler has been excellent for 25 years. Recently, the temperature in house started to decline. The recirculation pump has been changed, and a new Honeywell thermstat fitted. Boiler fires up when the room is below 16 degrees, but cuts out when 18 reached It keeps coming on throughout the day, but never exceed 18 degrees (The same thing happened with the old thermostat)The New Room thermostat is set to 25 degreesAdditional Information: I closed down the boiler and then went through the To light the boiler procedure The Pilot light lit immediately However, according to the instructions, you then turn the boiler thermostat to 5, and the main burner will start. The Main burner did not startAnyone any ideas please