Problem with cold rads

[NellyD]

Hi
I have a problem with 3 cold downstairs rads. Have used Sentinal x800 to no avail. Had the affected rads off and flushed to no avail. Had plumber take a look who says we have problems with the plastic microbore being blocked somewhere on the downstairs return and suggested having it re-plumbed. The affected pipes are behind the wall. The system has not been power flushed.

There is occasional Luke warm heat to the rads but this is sporadic.

Would it be worth trying fernox ds40 and then flushing the system before all the Argo of a re-fit?
If so any tips on using the stuff, eg. how long to leave in the system etc. (I was thinking approx. a week)
I can use an upstairs towel rad to get it into the system, and hire a power flush to clean out afterwards but any advice or do's and especially don'ts would be very welcome.

Or is this a job for a pro?

I am on a limited budget after being laid off so could do without too much expense!!!

 

[PrenticeBoyofDerry]

f you have small diameter pipework and a sludged up system, it's a bloody headache! A chemical cleaner is going to have very little effect on curing the problem, firstly you need to clear the pipes of blockage, last time I had a similar issue, I disconnected the each end of pipe and compressed air through it, to blow it clear. Once you have resolved that then you need to address the reason behind sludged up system!
I would also inspect the rad valves for any build up!

 

[NellyD]

Ok, so to do that do I presume I drain the system and then blow the air through? I have took up the floorboards upstairs and found where the pipes running downstairs connect in. Would I have to remove all the rads that are not working before blowing air down?

 

[WilkyWay]

What type of system are we talking about? Open vent or unvented?

If you don't want to hire a power flusher what I'd be doing is taking of each pipe of the rads that aren't heating and attaching them to a hose from a tap and try cleaning them out that way individually, obviously leave a drain off open at the same time so your rads don't end up pear shaped!
That'll do the same thing as a powerflusher, will take a bit more time but it's free, unless you're on a water meter then you're only paying for the water.
Once it's sorted make sure you add some inhibitor so the problem won't happen again.

 

[NellyD]

It's a vented system.
Would it be best to use the ds40 before doing any flushing to help loosen or soften any blockage?
As I said there is sometimes some warmth getting to the rads so I would persume it must be getting some small ammount of flow albeit irregular.

 

[D_Hailsham]

Tlhere is occasional Luke warm heat to the rads but this is sporadic.

What happens if you turn off all rads except the problem ones?

 

[NellyD]

Still the same problem, also done balancing but no joy. Other rads in house including other downstairs one's are still fine. The problem started with one rad and then others went down.

 

[NellyD]

I have also shut off all the locksield valves to all working rads, still no joy.

 

[PrenticeBoyofDerry]

How long are the tails between any open ended section of blocked pipes, I doubt mains water pressure will unblock, any heavy duty sludge, the problem is during drain off the sludge form above drops to the remote tails.
If routes are short in the past I have used a length of electric singles cable to help clear it but when stubborn had to blow it out.

 

[goodadvicebob]

Ad a power flush chemical to the system 1 week in advance. Once the corrosion and sludge deposits have been loosened and mobilised, fresh clean water is forced through the heating system, pushing the contaminated water out through a full bore dump valve to waste. Radiators are individually flushed, without removing or disconnecting them from the system, by directing the full output of the pump through each radiator separately. At the end of the flushing process, the system contains fresh clean water and reinstatement of the system to normal operation takes only a few minutes.
System flushing will not remedy design or mechanical faults, which should be rectified, but in many cases it will cure the problems caused by these.