Hot flow pipe's, cold rads??

[Blocked pipe]

Hello guys, thanks for your interest to read this and maybe have some answers for me, I have a situation with a house's heating, 3 rads downstairs (all separate dropdowns) and two rads upstairs, the rads don't get hot (or even warm) down stairs (but the flow pipes do) and the rads upstairs get hot but only when the hot water is on, I have drained the rads downstairs and got hot water coming out of the flow (as they all have separate external drain offs for flow and return), but the rads still won't get hot and there all full of water, its a back boiler aswell, might it be the pump?, I've not had much dealings with back boilers, the rads all worked fine apparentley untill the father changed all the rads and valves over (and he put the trv's at the top if that makes any difference?) Many thanks for reading this and hopefully you have some answers for me.

 

[Winston]

Turn the rad off via the trv, then open one with the trv wait for it to heat up, then go and turn the others back on this sometimes helps the circulator, good luck

 

[Sanke]

Do you know why the valves are now at the top ? Are they on flow or return & are they bi directional ?

 

[Winston]

I would imagine the valves were fitted at the top to reduce the amount of copper used in the past when there were copper shotages, seen this a few times now and that the only explanation I can think of.

 

[stevetheplumber]

I would imagine the valves were fitted at the top to reduce the amount of copper used in the past when there were copper shotages, seen this a few times now and that the only explanation I can think of.

top and bottom connectios are actually the most effective set up look at the blurb at the bottom of any rad list and youll find thats the way the outputs were achieved and usually a correction factor for bottom entry

 

[Blocked pipe]

Yes they are bi directional valves, not woories about why the valves are at the top of the rads, just looking for solutions for getting heat into the rads, all valves are open and water can be drained from flow and return pipes?

 

[UKPITA]

Hi.

Have you tried turning the radiator valves off on the upstairs radiators to force the flow through the downstairs rads?? I have needed to do this on several jobs and has always worked so far...

 

[Blocked pipe]

Yeah, done that, no difference.

 

[moony]

how new are the rads this is a strange one! would suggest looking at pump - but if its hot all way round then you should have some heat in the rads at least

top and bottom are the best way to pipe rads - its done bottom bottom purely for cosmetic reasons

 

[fireblade]

Top and bottom connections were usually used on old single pipe systems like raf camps and schools

 

[UKPITA]

Can I check, do you have 1 or 2 header tanks/f+e tanks??

Reason why I ask is that if you only have 1 header tank in the attic you have a single feed, primatic system this would explain why the rads are hot upstairs when the hot water is on!!

 

[Rusty]

I thought the rad's with a valve at the top and one at the bottom were positioned like this for gravity circulation on systems before pumps were used.

 

[fireblade]

On a single pipe system the rads just about work on heat rising as the water flow goes straight past the radiator the heat risers to the top pipe and shoves the cold out the bottom valve on black iron we used to use swept tees to try and get a bit of flow through the rad