Odd back boiler plumbing..

chris_ie

Hi,

We have a stove with a back boiler and also have oil fired central heating. There are two zones in the house. You can heat upstairs/downstairs separately. We had a problem initially where the zone valves only worked properly for the oil. For the back boiler, it always heated downstairs. You couldn't just set upstairs. We got that fixed which allows us to heat upstairs much better in the evenings.

Its still not properly zoned as even with downstairs off, the radiators in the room with the stove still get heated. The other downstairs rooms don't though. So not sure what sort of way it is plumbed.

Now, today I've just noticed something else. I had the oil heating on at lunch and notice small noises from the stove (not lit). Stuck my hand on the pipe and sure enough, it was warm. The back boiler in the stove was warm too, so the oil heated water is making its way into the stove.

Can't find the original plumber who did the house, we bought it in 2012 and it was built 2006/2007.

Anyone know any reason it would be plumbed in such a way? I'm assuming the oil heated water coming back into the back boiler is an issue, but just wondering about the valve not having an effect on the radiators in the same room? When we have the stove on we sometimes 'boost' the oil for an house to heat the other radiators. So guessing that heated water is coming back in when stove is lit...

chris_ie

Have the heating on this morning again and radiators are hot. Strangely enough, the pipe out of the back boiler isn’t heating up this time….