I have an oil fired boiler which heats the water and radiators fine. I also
have an open fire with a back boiler. For all the time I've lived here I
thought the back boiler only heated the hot water, not the rads. However I
now find out that it should heat the radiators too. The reason for the
double system is that the previous occupier owned a coal yard so could get
all the free fuel they needed so added it to the already existing oil
system.

Normally I have the boiler on a timer to come on for an hour in the early
morning and about 4 hours in the early evening. That seemed to work fine.
However, if I also had the fire on, evenings and weekends for example, then
when the fire seems to reach a certain temperature it kick starts the pump -
which is right - but the pump also kick starts the boiler, which fires up,
even with the controller off. This means that I am burning ridiculous
amounts of oil unnecessarily.
Yesterday I had someone in to fit an immersion heater so I don't have to
have the boiler on all summer as it makes the kitchen too hot, and now, even
without the fire on, the boiler is firing up and heating all the radiators.
There it goes again on cue. I've had to switch it off at the power switch to
stop it. However if I now light the fire, the pump won't come on and I
might overheat the back boiler.
I've asked the guy who came yesterday what could be done about it and he
said he couldn't understand it and would need to go back to get advice,
however I doubt I'll hear from him again.

Can anyone here work out what is going on - sorry for the long post but I
couldn't think how to explain it more concisely.

Thanks

Liz


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.620 / Virus Database: 399 - Release Date: 11/03/2004