Cold Downstairs Radiators

[nfollows1982]

Hello all,

I've done a search in the forum and I know this is a recurring issue but wasn't sure if it was boiler specific so thought I would start a new thread.

I have a Potterton Flamingo RS13 boiler (which I believe is circa 70's) so it's not exactly a new system.

I also have an immersion heater and water tank upstairs which supplies our hot water.

Thought I'd give the boiler a fire up just to make sure everything is ok and the downstairs rads are stone cold, as are the pipes connected to them. The upstairs rads are heating up quickly and nice and hot.

One thing I will point out is that last winter I tried to balance the radiators and the flow valve on nearly all of them started trickling water so ended up with all flow valves on all rads fully open (and tightened) to stop the water dripping which gave us heating throughout the house.

So firstly and only at the moment I have bled the rads to dispel any air an that's where I am.

Q1. Will having all the rad valves fully open cause the downstairs rads to be cold, even though this didn't occur last year? If so do I need to turn upstairs off and see if downstairs gets hot?

Q2. If not, and I need to be looking at the pump, where the hell is it? It's not near to the boiler and it's not in the cupboard where the water tank is. So without wanting to pull up the floorboards upstairs, is there a logical route away from the boiler to follow to the pump?

Hope the above makes sense and any help would be great.

Thanks

 

[kbdiy]

Q1 - yes try turning off the upstairs rads first and see what difference if any;
Q2 - I believe it was possible for the pump to be mounted within the boiler casing but can't be sure if I dreamt that. Otherwise it's a case of tracing pipework from the boiler. The pump could have packed up so you will need to find it.

 

[Armo74]

Have you touched any manual valves in the airing cupboard? Maybe a gate valve with a red wheel on it.
What colour is the water that comes out when you bleed the rads?
Probably a balancing issue but maybe a blockage if its an old system and hasn't been maintained.

 

[nfollows1982]

Right I've turned alll the valves off upstairs and turned the heating up high and left it running. I've got heat to the pipe with the trv on the downstairs rads but the radiator itself isn't getting hot at all.

I went back upstairs and reopened the valves and rads were hot almost straight away and the trv pipe on downstairs rads then cooled.

Boiler is on kitchen wall and all pipes go upwards and through the ceiling. Assume under the floorboards of bedroom above. There is also what looks like electric cable from boiler going up too so would that be the power to the pump?

Radiator water when bled is black. When I closed the inlet valves on upstairs rads they leaked again and this was also black.

So I'm guessing this isn't good?

 

[stevensonplumbing]

It's probably a faulty pump - often the upstairs radiators can work with gravity circulation, but downstairs won't.

 

[nfollows1982]

Morning,

Just a quick update on this issue as it is now slightly better than it was before.

Still yet to locate the pump but have run the heating a couple of times with the upstairs rads off and got 2 of the 4 downstairs rads hot.

On turning the 3 rads on upstairs, these 2 rads downstairs also stayed hot and when firing up from cold they all heat up together.

So I'm now left with 2 rads downstairs that are still not getting any heat to them.

Any ideas if this is still going to be a pump issue or if I should be looking for another solution?

Thanks

 

[picasso]

Take the top off the trv,s and make sure the pin moves also see if there is water in the feed and expansion tank and that the ballcock opens when you drain water from the rads.

 

[shaunyab]

You could try turning all valves off except the two that are cold to force the hot water to them.
Like the previous post if they dont get warm after taking off the trv heads (dont forget to open the lockshields fully), you will need new trvs.
If they do warm up, open up the other valves to the system.
If they go cold again, the system could need balancing.

 

[shaunyab]

Just a thought, are the pipe sizes all the same or are the upstairs in 15mm and downstairs in microbore?

 

[ALCPlumbing]

I would suggest shutting all rads off fully except for either one of the rads that are cold. Ensure the lockshield valve is fully open and take the TRV head off and using a hard object placed on the pin apply a small amount of pressure to see if it moves down. If it doesn't then it has seized in the closed position. If this is the case gently tap the pin on all sides to see if it will raise up, if not use pliers but be aware it should on rise by about 3mm on average depending on the make if the valve. This will use the full force of the pump to hopefully get some circulation through the radiator. If successful repeat on the other cold radiator.
If unsuccessful you could try as a cheap option putting some chemicals in the system but in all probability given the age of the system you are long overdue a proper powerflush. If you do this make sure you get a filter fitted on the return to the boiler. At least you may not need to properly flush again when you come to replacing the boiler and a couple of doses of good cleaning chemicals may suffice. Let us know how you get on.
J

 

[nfollows1982]

Morning all,

Just wanted to say a big thanks to everyone who has replied and let you all know that I now have hot radiators upstairs and downstairs.

Turns out the 2 remaining dowstairs rads did have seized TRVs so once I'd managed to get the pins freed up and run the heating again all is good.

Although I have left myself with one problem.......when I closed the flow valve on one radiator upstairs and then went to open it up, the pin bit that you turn literally sheared off with it in the closed position.......ooooops!!

There's nothing to get the pliers on to ease it open again so was thinking of drilling into it to try and lever it open? Is that a sensible option or does anyone have any tricks of the trade?