£500 + VAT for a pressured system flush?

[RstJAB]

My problem with 2 rads not working has now extended to a loss in pressure from the old boiler. Had the boys in and they recon it needs a pressured system flush to see if there is a blockage. The flat is 1000 sq ft and has 7 rads, is it me or does that sound expensive, I thought it was more like £35 per rad?

I am also worried that a pressured system flush may cause a pipe to burst, is this a possibility or are the systems designed to take it - I am concerned as it is a first floor flat and it is quite old.

Any advice would be very helpful....

Thanks

 

[Bahco]

Try taking them all off yourself and flushing through with a hose first.
Then balance your system.

Is the supply pipework to these rads getting hot by the way?

 

[RstJAB]

no the feed pipes are not getting hot...

 

[Bahco]

Turn off all the other rads and try the pipes to see if they get hot. If not, then you need to flush out the blockage, etc.

 

[cozzmic]

Is your system pipe work in plastic. If it is then you could have problems trying to clear the blockage as I've seen it having to be chipped out of pipes with a screwdriver, pressure seen holding several bar and not moving it. So go canny.

 

[RstJAB]

all pipe work is copper, not plastic.

I think the flush is the only way forward as there is clearly a blockage....

 

[oilman]

If there's a blockage, a powerflush is pointless. If it's blocked nothing can flow. The only solution is to find the blockage and remove it.

One guy got me in to do a powerflush, but his problem was siezed valves, so I fixed them. He didn't need a flush.

 

[Paul Barker]

I don't understand your question, but would like to understand you problem.

Do you have two out of 7 rads not working at all?

What do you mean by loss of pressure from the old boiler?

Have you tried hitting the bad rads and especially around the valves with a rubber mallet or the but of a rubber hammer effing hard as you dare until water goes round the rads?

 

[RstJAB]

Hi Paul,
Right here is the problem. 2 of the 7 rads don't work at all, the supply pipes are not even warm. The pressure guage on the boiler is at 0.1bar, so I have filled it up via the supply tap until the pressure reaches 1 bar.

When the heating kicks in the pressure rises to 2.5 bar as you would expect. When the heating goes off the pressure drops to 0.1 bar again.

There is no water coming from the overflow pipe so my imdeiate thought was that there was a leak, hence why I called in a plumber. They have advised a power flush to try and unblock the rads. If that doesn't work they suggest replacing the boiler.

The strange thing is that the inflow pipe on the boiler gets as hot as the out flow pipe, so there is circulation.

I am totally stuck and just worried that I have a leak that is getting worse and I live on the first floor and don't want to upset my neighbours downstairs

I am hoping to get a second opinion today but if this rings any bells with any professionals out there then that would be good!

Thanks

 

[oilman]

Someone should check your expansion vessel. It probably has no air in it. To check for leaks, put 1 bar in and leave the boiler off. If there's a leak the pressure will drop.

 

[RstJAB]

Thanks oilman, will give it a go.

 

[slippyr4]

is it me or do people think that 1 bar to 2.5 bar pressure change from hot to cold is a bit much? is water coming out of your PRV release pipe?

 

[RstJAB]

no, there is no water escaping, incidently I don't think 1 bar to 2.5 bar is too much but I do think 0.1 bar to 2.5 bar is!!

 

[Nige F]

Diaphragm gone in pressure wessal