power cuts and back boilers/pumps

wrightk

Hi all,
Getting ready for another storm here and inevitably another power cut!

Just wondered about my setup and whether its safe to use in a cut.i have a multi fuel with back boiler, pump that feeds 6 rads.it was recently repiped to convert it to a fully pumped system. Im a bit nervy about running the system during a power cut and tend to just drainbthe hot water during a power cut.

I understand the concept of gravity feed,kind of !but just wondering if thevsystem will be ok to run!

brownhandbag

In our experience, if the pump is not running (ie power cut) then the water will boil in the pipes and give you a loud knocking noise. You can not mistake it...is like a haunted house banging the plumbing.

We use a parkray with back boiler and in a power cut we close off the back flue to forward/general fire setting and have had no problems, but obs the rads etc will grow cooler eventually.
If you are really concerned the thing sounds like its in trouble then have a bucket of water handy to put your fire out, but if you shut off the flames to the boiler and keep an eye on things it should be ok.

molerat

We had parkrays in a few houses and found running off the hot tank cooled the system down fairly quickly.

highrisklowreturn

Yip, ensure all valves are open on the upstairs rads, to ensure max uptake of gravity heat.


Incidentally did either of you have constant problems of air in the radiators?

brownhandbag

highrisk We had a nightmare with air when we fitted the system, we replaced a baxi open fire/BB system. But once we had gotten all the air out it has been great ever since. PS we are in a bungalow but if we had an upstairs that would make sense too.
Thx Molerat for info I did think I would run off the hot water if we were stuck and thought that ought to work, but haven't had to try it yet so great to know it will.

Cardew

Notwithstanding the advice above, there must be a safety vent.


The diverter valve(Y) to the HW tank could be in wrong position if there were a power cut and you cannot have a situation where the water can boil in a 'sealed' system.

wrightk

Thanks.the way the system is set up everything is taken care of via the charnwood control unit and there is high and low stats on pipes.its quite a big system for the house so we have to run it quite hard which is why I worry.
For about a year we only had the pump running two rads downstairs and upstairs running the rads(poorly) on gravity due to it being piped wrong.since then its been repiped to a fully pumped system so im not sure if in a power cut i would have any backup.

Is there any option here for a UPS bearing in mind the pump is wired into the control unit or is this too overboard.power cuts are pretty regular here and would be nice to have a source of heat/hot water regardless of electricity

highrisklowreturn

Not sure how I'd go about purging all the air from the system as it's open and more just seems to get in. I had a plumber recently redivert the cold feed into the cylinder from the top to the bottom but this didn't seem to help. I hoped this would have done more as the fire has boiled over crazily on a couple of occasions - think the noise you get when lowering chips into a fryer type of boiling - which left me at the first rad in the system, with a large pot, trying to drain as much from the rad as possible.


Although other people I know have said about running the hot water off, this didn't seem to stop the parkray boiling over in my case, so assumed it must have been a large air pocket in the pipes right above the fire.