Electrical mechanical valves central heating

[Dave1341]

The system had been left off for 10 months and the pump refused to come on this is why I changed it

 

[BlueLoo]

The system had been left off for 10 months and the pump refused to come on this is why I changed it

Was the pump cavity clean or dirty?

Maybe the system has choked up with sludge.

Try a strong cleaner perhaps?

 

[Dave1341]

Yes just 3 settings manually operated by a rotary switch same as previous pump

 

[BlueLoo]

I'm going with sludge in the system.

Won't do any harm to remove the rads and flush them out, and try cleaner would it?

I wouldn't go changing stuff ad-hoc.

Others may know better.

 

[JohnD]

If you turn off the working radiators they go cold!

And what happens to the others?

You may have a balancing problem or an air bubble.

 

[Dave1341]

fairly clean inside put water from draining in a beer glass looked pretty clean. ie if it had been offered as a drink of water it would have passed

 

[JohnD]

Just to check

If you turn off the working radiators they go cold!

because it was a serious question

Do you mean you tried it, and that's all that happened? Or you didn't try it, but you assume that's all that would happen?

I ask because the much shorter problem "some of my radiators are hot, and some are cold" is more common than you would expect, and the remedy easier.

 

[Dave1341]

No I was just trying to be clear as the water was. I might take a downstairs radiator off tomorrow and just see what happens ie any sign of sludge does the water flow easily from the valves ? put a hose in the radiator to see if water flows easily through it. I am clutching at straws but hey ho thanks again to all!

 

[BlueLoo]

No I was just trying to be clear as the water was. I might take a downstairs radiator off tomorrow and just see what happens ie any sign of sludge does the water flow easily from the valves ? put a hose in the radiator to see if water flows easily through it. I am clutching at straws but hey ho thanks again to all!

You might be surprised at the muck that comes out!

 

[Hugh Jaleak]

Pump could have seized after 10 months of no use, did you try anything to free it off before changing it? I would suspect you have either a blockage or an air lock, or possibly both now. Pulling some water out from the middle of the system wont tell you much, again if the system hasn't been run for 10 months, all the crud will have settled out in the low spots.

I'd also try running a decent strength magnet along the pipework around the pump, and especially where the vent and cold feed enter the system, if there's any sign of it attracting then that is a sign of a blockage. (You will need a stick to clear this....)

 

[Tricky-Dicky]

I notice that you have 4 motorised valves, Hot water, Flat, Upstairs ? and Downstairs? Do any of these 4 circuits working ie Flat and/or Hot water?

 

[ericmark]

Have you bleed feed and return? Turning off TRV or Lock Shield valve so bleeding feed and return can held some times, simply opening bleed valve with TRV and Lock Shield both open will bleed the easy route. Alternating turning TRV or Lock Shield off will ensure both feed and return both bled.

 

[Dave1341]

So a big thanks for all your ideas! 're flushed and back filled with a garden hose mostly all works still clear water comes out. The main thing is absolutely nothing to ground floor. So radiator off and flush I through . So much more liky Muck rather than a valve. Difficult to remove radiator so I guess w d 40 and wait The system does use micro note pipe

 

[JohnD]

if the sediment and sludge has settled, the water will appear clear.

But adding a cleaning chemical such as X400 will loosen it and it will circulate round in the water, which will often go inky black.

Once you have circulated it for a few weeks, you can drain it out and rinse the system, and all the dirt that was in suspension will be out.

Adding a magnetic filter will gradually trap the remaining particles that get into the water.

 

[Dave1341]

Thanks for the info just taken off a downstairs radiator and flushed it, moderately black sludge inside. When I re attached it I closed all the other downstairs radiators and tried to force the heat through the cleaned radiator but nothing no even getting slightly hot. Where should I go from here ? Take the e m valve from the pipe and see if it is clear when opened or go for the flushing chemical but I might not be able to get the chemical into the ground floor pipes?

Thanks again to all