Hi, this has been a long standing problem at my property, but determined to fix it since recent activity. I recently had to replace the ball valve in the header tank. In doing so I drained the system fully to clean half an inch of sludge out the bottom. I should say that the system is old - property built in '64. Whilst the system was drained I removed 3 of the rads downstairs and flushed them through with a hose. Needless to say an awful lot of black water came out of each. On replacing the rads, the same 2 rads refused to heat fully, so no change. The following week I drained the system a further 2 times, changing all 4 valves on the offending 2 radiators. This made absolutely no difference at all. My next plan is to install a Magnaclean on the return pipe before the boiler and add some Sentinal X800 cleaning product - but I fear this will also have little effect. Any comment and advise warmly welcome! Thanks.
2 Radiators not heating up fully
- Thread starter S30fry
- Start date
What part of the radiators are not heating fully?
1)If top half is remaining cold, they need bleeding as air is trapped.
2)If bottom half is remaining cold, you still have sludge in the system and the system needs a really good flush, possibly a power flush.
3) If the whole radiator, then the system either needs balancing or you could have blockage in pipes to radiator.
1)If top half is remaining cold, they need bleeding as air is trapped.
2)If bottom half is remaining cold, you still have sludge in the system and the system needs a really good flush, possibly a power flush.
3) If the whole radiator, then the system either needs balancing or you could have blockage in pipes to radiator.
I'd say some pipes are blocked. I explain how the Scottish Gas guy fixed my blocked pipes in reply 14 of this thread...
http://www.diynot.com/diy/threads/one-bad-rad.451930/
http://www.diynot.com/diy/threads/one-bad-rad.451930/
Thank for replying.
I don't think it's trapped air as I went round all the rads twice bleeding them when I refilled the system. It just takes an awful long time for the 2 rads to warm, say an hour, and even then they are 'slightly' warm (all over) and not hot. I fear there may be a blockage in the pipes. Also there is a significant temperature difference to the inlet pipes going into the rad on the rad that works well compared to the other 2 rads. Hence, thinking of getting a Magnaclean fitted and adding Sentinal X800 cleaning pro
I don't think it's trapped air as I went round all the rads twice bleeding them when I refilled the system. It just takes an awful long time for the 2 rads to warm, say an hour, and even then they are 'slightly' warm (all over) and not hot. I fear there may be a blockage in the pipes. Also there is a significant temperature difference to the inlet pipes going into the rad on the rad that works well compared to the other 2 rads. Hence, thinking of getting a Magnaclean fitted and adding Sentinal X800 cleaning pro
Have you tried turning all other rads off an the system other than the two that are not heating up. It could be a balancing issue if they then become hot.
I wouldnt add sentinell X800, its far too aggressive for what you want to do and can not be left in the system, X800 is best used with a powerflush machine, you would be better using X400
http://www.sentinelprotects.com/uk/...-x400-system-restorer-or-x800-jetflo-ultimate
http://www.sentinelprotects.com/uk/...-x400-system-restorer-or-x800-jetflo-ultimate
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