Oil Boilers and Radiators

We have an oil-fired, floorstanding boiler. Our bathroom radiator has no valves on it, and seems to come on at odd times, independently to whether the heating is on (the hot water might be, but the heating isn't).

I vaguely remember someone once telling me that due to the type of boiler we have, there had to be one radiator that didn't have valves on it and hence could not be turned 'off' but I can't remember the reasoning behind this.

Anyone know what this is about?

Tony.

Reply to
Tony Wood
Loading thread data ...

If the central heating is not demanding heat, and the cylinder gets up to temp, and the valve to that closes, the water flowing through the boiler stops, and can boil even though the boiler has shut down, from residual heat. If there is a radiator that does not have a valve on it, then the water goes through that instead.

Reply to
Ian Stirling

The idea of a heat-dump radiator came about with solid fuel boilers where the flame doesn't switch off when the stat is satisfied. As the hot water cylinder was usually heated up by gravity circulation from the boiler a suitably located radiator was installed to dump heat when the cylinder got hot. sometimes this would be installed in the loft but this wasted a good deal of heat to no use so a bathroom radiator was considered a suitable alternative and piped in parallel to the hot water cylinder. Some builders kept up this tradition even when other fuel boilers were installed from new and there is yet another alternative arrangement where the bathroom radiator is piped as a bypass to both heating and hot water with an S plan system. with this last option you have the benefit of warm towels whatever the boiler is heating up. If having the bathroom radiator on bothers you it can be turned off as long as your boiler thermostat is working OK

Reply to
John

In message , Tony Wood writes

Some boilers must have one of the rads permanently open (our Halstead Ace High being one of them). The rad will usually have 'lock shield' valves on which can't (easily) be turned off.

If your boiler must have this arrangement, you have the option to install an automatic bypass valve somewhere in the system and then put standard thermostatic valves on the bathroom rad.

Hth Bill

Reply to
invalid

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.