Strange radiator problem

[LindseyS]

Hi all,
I am hoping someone can give me some advice - I have a strange problem with some of my radiators being cold.
I rented out my cottage while working away, and the tenant decided to turn off all the radiators at the valve. The boiler (gas gravity system running 7 radiators) I know is fine, as it just went through a landlord annual safety check and service right before the tenant moved out. However, when we switched the boiler back on and turned the valves back on, four of the radiators heated up fine, but three were stone cold.
There doesn't appear to be any air in the system, and the whole radiator is cold, so it's not that they need bleeding.
It's been suggested that they might need desludging, but someone else has since suggested that a sludge problem would give a similar effect to air in the system and the radiators would be partially warm.
If you push in the valve you can hear the flow change, so there does appear to be flow. Also the pipe going to each radiator is hot.
I know a bit about plumbing but not enough to work this one out - I am totally baffled. Any suggestions would be really welcome.
Many thanks
Lindsey

 

[LindseyS]

Ok we sprinkled the carpet But this is so weird, water seems to be coming out fine - with the lockshield open, opening the TRV on the cold lounge radiator pushed water through strongly.
On a bright note, it was nice clear water, not black and dirty - which I guess is good news for both a power flush and the carpet
The gurgling coming from the boiler room is making me think airlock - as it doesn't appear to be in any of the radiators, maybe in the pipes?

 

[joni os]

When I said open lockshield you where meant to turn spindle in anti clockwise direction, it sounds as if you've undo the lockshield, please tell me I'm wrong.

 

[LindseyS]

The lock shield is fully screwed anticlockwise, we checked the ones that were working to see how they were sitting first. Hubby just wanted to check there was flow - which there seems to be. It's baffling him as he tells me that everything seems to be implying there's flow either end but nothing going through the radiator - which seems to defy everything I know of the laws of physics

 

[joni os]

If rad is getting hot there is flow. If rad stays cold no flow, assuming no air in rad. Very often if rad turned off for period of time a small amount of sludge can prevent flow but once circulation established everything fine there after. Good luck with your endeavours.

 

[jtsplumbing]

I know it may a stupid question But can you feel if Pump is working ??

 

[chris watkins]

I know it may a stupid question But can you feel if Pump is working ??

Could also turn pump up to speed 3 until flow is established in rads, then turn back down.

 

[rocketmanbkk]

Has op tried opening one rad at a time to force through? Start with ones that don't work & open others up.

 

[joni os]

See concurrent thread,"Central Heating-Possible Blockage", Much good advice, may be applicable.
Bleed circulating pump by loosening central screw. Air in pump will effect performance and damage pump. Your mention of gurgling noise warrants investigation.

 

[rpm]

its good advice your ok

btw im catching you

Now you`ve lost me.

Not sure it warranted a PM however, guess we are Yin & Yan as in Quality over Quantity. :smile5: And stop stalking my post count surely you have better things to do. lol

 

[ShaunCorbs]

Not sure it warranted a PM however, guess we are Yin & Yan as in Quality over Quantity. :smile5: And stop stalking my post count surely you have better things to do. lol

Didn't want to put the topic more of topic

 

[chris watkins]

Didn't want to put the topic more of topic

Is this the forum equivalent to verbal diarrhoea ? Can we take some IMODIUM please.