Gravity fed heating system plumbers can't fix?

[Martin20354]

Hi
I have a Potterton Profile 50e supplying hot water to a copper tank. There is a pump off the cylynder for the central heating system controlled by a room stat. There are no diverter valves (single or 3 way) anywhere in the system. My bathroom was re-plumbed 2 years ago and a standard single panel radiator replaced with a heated rail radiator. Since around this time we have an issue with radiators.

When the hot water only is on, the upstairs radiators also come on regardless of room temperature resulting in having to turn off all the upstairs radiators. The downstairs radiators work fine and only operate from the room thermostat.

I have had the tank, pump and associated plumbing all replaced but still have the same issue.
Looking at the Potterton service manual there is an option to have the bathroom radiator on all the time which is where I think the issue lies.

I have engaged 3 different plumbers none of which seem to know what the issue is. I think I need a plumber with many more years experience than I had so far

Any help would be greatly appreciated

 

[picasso]

Have a check valve installed on the return to the rads, that will stop the unwanted circulation.

 

[mrStat]

You have had everything replaced but they left you with no additional controls? Part L of the building regs advises this should be converted to a fully pumped system when appropriate - A cylinder change IMO is the right time to convert to fully pumped.

As for the heating on upstairs - Do you have an AntiGrav valve fitted? If so, it is probably stuck open and just needs a good whack, replacement or ripping out and converting to fully pumped. Or someone has played around with the return connections when they did you bathroom works. Sorry, I probably agree with you in the fact that you need a better plumber.

 

[Martin20354]

Bit confused as it used to work without and antigrav or check valve, but now it doesn't. Would it matter if the bathroom rad was connected in reverse?

 

[picasso]

You have the choice of ripping up floorboards, carpets ect trying to find out what the other plumbers may or may not have done and perhaps not find out what has changed or simply fit a check valve to stop the unwanted circulation, choice is yours.

 

[Martin20354]

Any tips on how and where to fit it? if it's heating the rads without the pump on, Not sure where it should go.

 

[JohnD]

You are right in thinking that a more mature heating engineer will be very familiar with your profile, and quite possibly rather fond of them. Look for a local independent rather than a big company.

on the Gas-Safe site you can see their photos, so look for one with some wrinkles https://www.gassaferegister.co.uk/

When phoning they might indicate if they like Profiles or not.

Converting to fully-pumped is the right thing to do and not a very big job, unless you have to take up a lot of floorboards or something. It would be a good time to add a Magnaclean or similar, and do at least a DIY chemical clean. When you start pumping an old gravity system a lot of old sludge and sediment will get disturbed and start circulating.

 

[ianmcd]

on the Gas-Safe site you can see their photos, so look for one with some wrinkles https://www.gassaferegister.co.uk/

Is that why I am going wrong, I really need to update my photo and make myself look a lot older

 

[dilalio]

Wrinkles and shot knees

 

[Gasguru]

When a customer tells me it's an old gravity setup alarm bells ring...ie. it's prehistoric, the customers a tight wad etc and I'd normally give 'em a miss. Not worth the agro. So you might find it hard to find quality experienced installers willing to look...there's better systems out that are more likely to result in a fix and payment.