A tip for those with an outside boiler

Dan Jaman

I found this out the hard way, several years ago.
Arrange the electrical feed to your circulation pump so that it can be switched on independently of the boiler. When you know there's a period of seriously sub-zero weather coming up, switch the pump on and leave it running continuously - it won't do any harm and it only consumes around 35W or so.
What this does, is takes a little bit of heat from the house and circulates it to the boiler, preventing the pipes from freezing up. Even if you run out of oil, this will still work- the boiler doesn't need to be running. If you haven't run out of oil, the boiler will still come on and off as usual and heat your house, but the most important thing is the pump will keep on running and prevent freezing of the pipes.
I switch my heating pump on at the end of November and keep it on until March. No problems here.

There's been a few people around my area have been caught out by frozen ground putting paid to their water supplies and heating pipes, when in previous years it wasn't a problem. Many of these installations were done in good faith by builders and plumbers who didn't seriously expect these kind of conditions, but really they should have known better, as there was a requirement for pipes to be buried about 18" deep. The regs now require nearly a metre deep, if I recall correctly, but I'd be surprised to see that even on most of the new builds.

CJhaughey

Dan Jaman wrote: »

there was a requirement for pipes to be buried about 18" deep. The regs now require nearly a metre deep, if I recall correctly, but I'd be surprised to see that even on most of the new builds.

2'6" is standard in the UK on the continent 750mm is standard and they never seem to have the same degree of chaos as here and the North. Despite seriously cold winters.
My local council installed my stopcock on the road verge at 40mm below ground:rolleyes: and it wasn't pleasant having no water for 5 days. I am going to write and ask if they will install it at the correct depth.

cabledude

That is an excellent idea. And could be done at any time with not a huge amount of work..... Just to think what people around the country without heating that could have been prevented with this simple little alteration.....

YouTookMyName

Would it not burn out the pump quicker?

Dan Jaman

YouTookMyName wrote: »

Would it not burn out the pump quicker?

Not so far and the same pump has been running for seven winters. It's not even a decent Grundfos, but a cheapy 40quid one from Heatmerchants.

YouTookMyName

Dan Jaman wrote: »

Not so far and the same pump has been running for seven winters. It's not even a decent Grundfos, but a cheapy 40quid one from Heatmerchants.

Fair enough, Good tip that.

CBYR1983

Any risk if boiler is on but pump is somehow not? Mine are both on same switch, I imagine this is the standard?

Dan Jaman

CBYR1983 wrote: »

Any risk if boiler is on but pump is somehow not? Mine are both on same switch, I imagine this is the standard?

Well, yes. The boiler will overheat and cut out, then go into a reset situation.This is designed for in any boiler, as pumps can and do fail.
It's a simple matter to arrange a seperate feed for the pump, but you really have to be quite familiar with wiring. Many installations have the boiler and pump on a socket in the boilerhouse, which is designed to provide the necessary break of supply when servicing.
It would be fairly easy to arrange matters so the pump comes on without the boiler firing. Even if you don't want to change the wiring, you could simply switch off the boiler and put the timer on 24/7; that way the pump will run - check this by feeling the pump for vibration.
It's hard to give a detailed answer because every installation is different, but some general principles are usually followed in most instances.

Buford T Justice

CBYR1983 wrote: »

Any risk if boiler is on but pump is somehow not? Mine are both on same switch, I imagine this is the standard?

Yes, its standard. If the pump fails, the boiler will boil over and trip the high limit stat, and will stop working. Should this happen, I wouldn't recommend touching it for quite a while as the water will be boiling within the unit itself.