New boiler but one cold rad.

[stuartadair]

Hi
Had a new boiler fitted yesterday and now have wonderfully hot radiators in the house, all apart from one which is stone-cold. The new rad was installed last week and is brand new with a new TRV and replaced an ancient old rad that was deemed to be unsuitable for the new boiler to work with. The old rad never got warm either but we always put that down to its age.
The installer ran the boiler with all other TRV's closed but still couldn't get this one to work so came to the conclusion that there must be a kinked pipe somewhere which is out of scope for the boiler installation job. Its a microbore system. Opening the bleed valve gets me cold water under pressure.
What do you think? Does a kinked pipe sound realistic ?

Many thanks
Stu

 

[PrenticeBoyofDerry]

It could be a kinked pipe or blockage in either the flow or return. if only one pipe is blocked you could still get pressure at the radiator from one of the legs, but as the water cannot circulate you will not get the radiator to warm up.
Some further investigation is required on the pipework to the radiator, that is assuming the new valves are both open and functioning correctly.
You could be brave and close both rad valves, drain radiator down, then disconnect valves from rad, and open each up to see if water is passing. If one is not, then remove/loosen that valve from tail pipe and see if water is passing, if not you have a blocked pipe. If you have water passing, then it is the valve.

 

[stuartadair]

Hi. Thanks for the reply. You've just inspired me to take a look at the pipework in more detail. Every other rad flows from a manifold just under the boiler and returns to another one at the end of the 22mm flow marked in blue (Which I assume is the return). My dodgy rad flows and returns from the manifold marked in blue so its no wonder that its not getting hot. I spoke with a neighbour who told me that when the house was built in 1971 the room where the rad is was garage and it was converted at the last minute to a dining room so I suspect if was a Friday afternoon job and has never worked properly from day one. I think the best option is to have it piped in properly as are all the other rads. Many thanks

 

[Agile]

Not only is it the best option but it is the ONLY option.

I know that the boiler installer was probably just concentrating on his paid job but I would hope that my inspection before quoting/starting the job of replacing the boiler and rad would have identified such a basic fault.

If anyone were to think for a moment then they would realise a radiator can never stop working just because of its age. Its only a bit of metal containing flowing hot water!

Tony