Help with radiators

[mike14017]

Hi


Totally lost what to do next.


We have a Worcester combi boiler that is about 12 years old. It works great with very few problems.


Recently I decided to clean and flush the system because 2 of the radiators were not working and the rest were ok at best.


I flushed the system of the old water, I did this on every radiator.


I refilled the system and added cleaner.


I left the cleaner in for 2 weeks, then flushed the system again every radiator one by one.


I refilled the system and added inhibitor.


I bled every radiator.


Now all the radiators are working great apart from the 2 that weren't working before.


The inlet pipes to both radiators are getting hot, I have tried to turn off all the other radiators but these 2 are still not getting warm.


I have "blown" through on the 2 radiators for air locks, but still nothing.


I have looked on various forums and videos and I am now stuck as what to do next.


Any help would be greatly appreciated.


Many thanks


Mike

 

[jtsplumbing]

Have you opened the locksheild valves ? what size pipes have you got ? if flow is getting hot problem is on return pipework,

 

[mike14017]

Hi

Thanks for the reply.

10mm pipe.

I've opened and shut the lockshield valves, they work fine and are currently open.

To flush the radiators, if I can descibe this correctly, I took off one of the plugs on one end, of the radiator at the top, I then attached a pipe to this, I turned the lockshield off and left the inlet open, I then flushed water through using the top up valve on the boiler. I then reversed this shutting the inlet and opening the lock shield. In both cases the water flowed freely.

If the water is flowing freely when I do this, can there still be a problem on the return pipework?

Regards

Mike

 

[JCplumb]

Might just need balancing, what happens to the cold rads if you turn off all other rads?
If the cold rads are the only downstaits rads - look at your pump.
Find any zone valves and make sure they are operating when heat is called for in that zone.
They would be my first three things to look at, unless the customer hadn't offered me a brew by step 2, then there would be 4 things on the list.

 

[jtsplumbing]

Waste of time, only way you are going to clean out radiator is to remove it from the wall, take outside and flush with hose pipe (Turn rad upside down) replete with all other rads, doing it in place you are pushing sludge into pipes, when radiator is off wall open each end of pipe (One side at a time) and use filling point to run clean water through pipe, do each end on each radiator 10mm systems are hard to flush, stuff gets stuck in manifolds.

 

[mike14017]

Hi

I appreciate the replies

Might just need balancing

I balanced the upstair rads, if this correct " Turn lockshield off and a quarter turn on"

what happens to the cold rads if you turn off all other rads?

They stay cold

zone valves and make sure they are operating

If you mean the TRV they work ok as far as I can tell

Waste of time, only way you are going to clean out radiator

Watching a lot of videos and reading forums I thought that this is what I would do initially. We have got solid floors downstairs and all of the pipes come from upstairs. Three of the radiators I can't drain (which are downstairs) one of them is a big double in the lounge, which is one that won't get warm. Two of the radiators have valves on them that I cannot get to work (I have asked at the local plumbers supplies and looked online and can't find out how they are supposed to work), the big double in the lounge does not have a drain on it all.

How, if it is possible, do I drain the 3 radiators without flooding the rooms?

Regards

Mike

 

[jtsplumbing]

Turn off valves if possible, pull back carpets , small tub & bucket, undo connection to radiator and drain out rad a bit at a time until rad is empty, repeat with other rads, fully drain system, replace faulty valves, fit new valve for one that has a combined drain off, If not feeling comfortable about doing it then call someone in

 

[mike14017]

Hi

Is there anything else you can suggest I can try before I resort to taking all the radiators off, it's a fair bit of work and time.

Regards

Mike

 

[plumben]

Call a plumber?

 

[jtsplumbing]

Welcome to our world ! these sort of jobs do take some considerable time, and with micro bore pipe it's even more of a problem, and can work out to be costly to resolve , If you have the time it will save you money, allow at least 2 days, once you have done the flushing with water & refilled system add a heavy duty cleaner I use Fernox F5 run system for at least a week on max temp, drain when system is hot, rinse though and refill adding Fernox F1, worse case is you may have to replace some pipe work, But make sure that you install drain points on each G/Floor radiator

 

[Frog67]

Change the TRV's, 10mm pipe is restrictive enough, if the rad valves are not opening fully then the hot water will just take its easiest route.

 

[Gary80gas]

Remove rad, run system hot and run into bucket flow and return see what flow is like. If the water isn't circulating it must be restriction or pump if pipes only are hot. I f you run heating with other rads off does heat flow from boiler? Try replacing one rad and valves, they are fairly cheap if small rad.