Ideal Classic Boiler

[infinitym2]

HI wonder if anyone can help, I have and Ideal Classic Boiler with a Drayton LP722 Lifestyle Timer and Drayton RTS1 thermostat. the problem I have is that when the heating comes on, once it reaches the desired temp, the boiler turns of, then within two minutes its back on again for 3-4 minutes and then of again for two minutes and it keeps doing this until we either turn the thermostat up or down or the timer clicks off. I have changed the timer, the thermostat and the pump. As far as I can tell the water is behaving correctly. I know that this particular boiler does go of and on constantly, but my sister has the same boiler and hers have intervals of 10 minutes, not the short ones that I am getting.

the problem is my gas bills have gone through the roof (=A380-=A3100 monthly where they should be =A330-=A340)

any help would be appreciated

thanks George

[Phil]

Is there a hysteresis setting on the thermostat (ie/ a 'deadband' which it has to go outside of before re-firing the boiler)? It sounds like the 'stat is commanding the boiler to run from what you say, increasing the deadband (if adjustable) should stop it cycling too often.

[John]

The classic is a boiler which enjoys simplicity to achieve a very high reliability. The usual mechanical Ranco thermostat doesnt normally have any problems and its not advisable to prat about with it.