Range
range rated I have no idea, it’s 15mm pipe to the rad, and it’s a logic combi2
Cold radiator. Please please help
- Thread starter Theo1226
- Start date
No I have definitely balanced them, I turned them all
Fully open, checked the order that heats up first, turned all
Lock shields closed, then started with the rad that heated up first. My first rad is open about 1/4 turn on the LS, then moved onto the next, and opened just enough until it got hot, and so on. But when I get to the bad one, no matter how open the LS is, it doesn’t heat up when others are on
I would fully close all lock shields apart from the troublesome radiator. When it is up to temperature, move to the the next downstairs radiator and open the LS just enough to heat up. Repeat for the other downstairs rads. Check the troublesome one is working ok. Then move upstairs and repeat being careful to only open the LS enough to allow the rads to heat up.
So I closed all other LS and let the bad rad warm up, turned another downstairs rad 1/4, wasn’t hot after 5 mins, turned another 1/4, the rad got hot, checked the front room rad, and it’s gone cold. Maybe a blockage in the pipe leading to the bad rad, so when it’s only that being powered it’s enough to force through?
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iPad playing up, hence blank post!
I was going to say maybe 1/4 turn open is too much, but it looks like you've tried turning it down even more.
As per #10, maybe the pump output is low, worth checking the impeller isn't blocked with crud. Easier to balance the system with a strong flow.
Is the system laid out as it should be? When I moved into my first house (new build) in 1972, the heating worked pretty much OK, but I found if all the rads were turned off on the valves the pump wasn't dead-headed. The builders (still on site) agreed something was wrong. There were 2 parallel pipes and another pipe should have teed into the far one, but had gone into the near one. They corrected it. It wouldn't surprise me if there are houses on the estate wrongly piped to this day.
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Thanks for the info, I’ll be honest you have said a few things there that mean nothing to me, I can only assume it’s laid out correctly, but having only been here a few months I couldn’t be sure, it’s a early 80s build.
I’m starting to think it’s pipe to the rad, but when I drained direct from the TRV it was a powerful flush coming out
In my house, before it was fixed, there was a route from the pump to the boiler return, in parallel with the the rads. Somewhat surprisingly, there was still enough flow through the rads to do the biz. If yours is like that there is less pressure available across the rads, making balancing more difficult. This might seem a long shot, but you're in long shot territory now!
Unless there is a bypass to confuse things, you could test it by closing all the rad valves and see if the boiler protests (like banging)
But I'd check the pump impeller first, just 4 Allen bolts (after isolating the pump of course)
Thank you! I’ll give this a go! And you’re right I am in longshot territory! There was me hoping it was a stuck pin hahaha
Update!!
So it’s fixed! After speaking to a mate he suggested checking under the floor so I cut a hole in the floorboard and got under neath, there was a return and inlet T’d into the same pipe. Causing a constant loop
Essentially, so I capped off the return as it’s was basically stealing the flow from an existing pipe. I think anyway! Well whatever I did it worked and now it heats up perfect as does all the other radiators! Thanks all for the advice
So it’s fixed! After speaking to a mate he suggested checking under the floor so I cut a hole in the floorboard and got under neath, there was a return and inlet T’d into the same pipe. Causing a constant loop
Essentially, so I capped off the return as it’s was basically stealing the flow from an existing pipe. I think anyway! Well whatever I did it worked and now it heats up perfect as does all the other radiators! Thanks all for the advice
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I nearly suggested that it may be on the same flow and return as I've only ever encountered it once, but didn't because you said it heated up.
So that issues was on another rad downstairs! Not the problem rad!!
Brilliant! Glad to have helped. I only suggested that based on my personal experience, so pleasantly surprised it turned out to be the problem.
Unless something was changed when the new boiler went in, I assume it had been like that ever since the house was built in the 1980s.
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