Radiator working intermittently

[wardy1971]

Hi,

We recently moved into a house where the lounge radiator only works after the central heating has been on for around 4 hours (or it seems that that it works when the house temperature reaches around 19 degrees i.e just when you don't really need it!!)

The radiator in question has had an extra one run off of it at some point that is in the conservatory & that does not work either although we are not too bothered about that but we do want to lounge one to work!

We have had 3 plumbers come to look at it, checking the individual thermostat, & both this & the conservatory one have been flushed.

Any ideas? It baffles me that it works very effectively but only after the heating has been on for hours!

Thanks in advance

Wardy

 

[Best]

Does it heat up slightly for the first hour or two? Why I say this, is if there is a blockage in a pipe, rad valve or radiator, the flow can be so slow that the rad will take ages to heat.

 

[SimonJohns]

Try balancing the system

 

[Best]

SimonJohns is probably right. Assuming that you had the pipes to the rads flushed when the rads were, & the flow was good, then system may be well out of balance. Is the lounge one of the far points of system from boiler? Try turning everything else off. If rad works, then balance system, including pipes to hot cylinder if you have one. If this only improves it a bit, then it could be blockage or circulating pump.