Powerflush or Balancing?

Zippyfan

I recently moved to into my house which had been vacant since November 2009. I have signed up with British Gas on a cover plan for the central heating (£17 per month). On the annual service the engineer recommended that the system would need a powerflush at some stage.

In the last week I have turned on the heating to find out that the radiators hardly heat up, apart from two which are closest to the hot water tank. Everyone is screaming "powerflush!" but I am not happy with the quote of £808 (powerflush + Mangnaboost) from British Gas. So I decided to get a second opinion.

Got a gas engineer around from a local company who tried turning the two working radiators off. Genius! All the other radiators started to get heat to them. He tested the system with the hot water turned off and diverted just to the heating - bingo - all the radiators have some heat, and most are at a good level. This engineer recommends a balancing valve so that water goes evenly to the central heating and the hot water. But he did warn that there was a small chance that there may be a need for a powerflush if gunk is found to also be a problem.

Also, the local engineer noticed that the pipes leading into the radiators are 10mm - would this be a problem for powerflush?

Help - I feel like I'm on an episode of Watchdog. Which is it? The powerflush or the balancing valve? Or both?

gas4you

Try turning your pump up to a faster setting.

I have customers who BG said needed a powerflush and to make the system appear bad, had turned the pump speed down!

Zippyfan

Interesting that you should say that because when BG came to do the annual service the engineer told me that he had turned the pump down so as to buy more time before needing a powerflush. He said that I should not even notice any difference. Will try it now and let you all know!

Zippyfan

Radiators are a bit hotter. I think I'll give them a day or so to see how they go!

samtheman1k

All systems need to be balanced, regardless of whether there is gunk or not!

All your radiators should have valves on, just where the pipe meets the radiators, all you need to do is adjust these until all radiators have the same temperature drop across them. It is easy to do.

Powerflushing is only done when it is full of gunk.

Mikeyorks

Zippyfan wrote: »

This engineer recommends a balancing valve so that water goes evenly to the central heating and the hot water.

Probably a very sensible engineer. If the central heating feeds are 10mm and the coil / feeds are 22mm ........ then the hot water will take line of least resistance and opt to go around the coil.

Had precisely this problem (central heating 15mm and single pipe) with a new boiler 2 weeks ago where the water heating / central heating simply wouldn't co-habit. After a couple of hours playing with all the flow / return temperatures - the engineer restricted the flow on the 22mm side and it's been fine ever since.

The powerflush worked fine on 15mm (and certainly not £808!). Except - a bathroom radiator was moved when we first came here - and it's now clear the circuit was just extended as a spur. The result was that a lot of goo from the rest was washed into this 'backwater' by the powerflush and filled the ladder rack towel rail / flow valve. And (dual fuel) they're a sod to get off without getting the black stuff all over the place. Accomplished after a couple of hours - but I never knew a radiator could hold so much muck when we flushed it outside.