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Radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in cars, buildings, and electronics.A radiator is always a source of heat to its environment, although this may be for either the purpose of heating this environment, or for cooling the fluid or coolant supplied to it, as for automotive engine cooling and HVAC dry cooling towers. Despite the name, most radiators transfer the bulk of their heat via convection instead of thermal radiation.

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  1. Jonnyh88

    Help with setting Grundfos pumps.Single Pipe CH heating system.

    I'm trying to get to grips with a system I have inherited as a new home owner. I know that single pipe systems are crap and should be replaced, but that's not an option right now so I have to make sure what I do have is set up correctly. My bills are astronomical - £6-700 a month right now, and...
  2. M

    Two lukewarm Radiators

    Hello! Overview: typical 3 bedroom 1930's semi-detached property. Had a single storey ground floor extension circa two years ago, during which time the boiler was replaced with an Ideal Independent and moved from back bedroom into the loft above. Problem: since the boiler was replaced and...
  3. T

    Trv not turning off, but heads are ok (work on other radiators)

    Hello, we have bulldog trvs on all our radiators but have a problem with 2 of them. The 2 upstairs radiators do not turn off (4 downstairs all work fine). If I switch the trv heads, taking one which works downstairs and putting it on an upstairs radiator it also does not shut off the radiator...
  4. harpermin

    A number of radiators not heating up

    Hi Just looking for some suggestions on what to look for/try next. Up until last weekend, our oil fired boiler central heating was working fine, all radiators heating as required. We then had an issue of a mouse deciding to go for a exploration in our air intake and causing it to begin to soot...
  5. L

    4 radiators not heating up at all

    Hi There, I have plastic microbore central heating piping, with 15 radiators around our 19 year old house, we have had issues for years with some radiators being cold, occasionally getting one of them to work, but sometimes causing another to no longer work. One plumber said, as we had an open...
  6. K

    New radiators not heating

    Hi, I have a new extension with 3 radiators (it’s quite a large space). I had 2 radiators in my original space so I have 1 extra (albeit one of the others is larger than its predecessor). The pipework to and from the radiators is new (the original system is a one pipe system but we are...
  7. Bogart

    TRV controlled radiators passing by

    Is it me or do others have the same. I have out of 23 rads in the house maybe 6 that pass by even when on the frost setting with the room temp at 10 degC. It is as if they need a small solid washer or similar inserted into the trv head to make it act a tad before it would alone. The rads do not...
  8. R

    advice on how to flush out the pipes on my central heating system.

    I need advice on flushing out my central heating system. Lower two floors underfloor, top floor radiators. Oil fired system
  9. E

    No programmer to control radiators

    I recently moved into a new property which has a gas boiler and: (1) A hot water tank - this is controlled by a Hive timer programmer (all good); (2) Wet underfloor system on ground floor - this is controlled by Heatmiser thermostats (all good); and (3) Radiators on first floor and towel...
  10. ndfred

    Range Rating: Just Add up the Radiators’ Heat Output?

    I have a Vaillant boiler and want to set d.0 to something sensible, right now it is set to auto and can range from 6 kW to 37 kW. Adding up my radiators' heat output from the Stelrad website gives me 25.7 kW and my hot water cylinder coil rating it 23.9 kW. The Heat Geek Range Rating Method is...
  11. Z

    Help needed - radiators on one pipe system

    Hello all, I bought my house last year and recently had a couple of radiators swapped for modern triple columns. Since they were installed they are extremely slow to heat up, much slower than the old ones. I had the plumber back to try and fix this, and he flushed the system, even though this...
  12. D

    Cold radiators!!!!!!

    Hi I turned my heating on few days ago for the first time this winter and bleed the radiators and it all worked fine. Turned it on again tonight and the boiler fires up but all the radiators are stone cold! Any advice on what it could be? The pump in the airing cupboard is pumping
  13. S

    Trouble with bleeding very old radiators in rented accommodatio

    Hi everyone, I am looking to bleed the radiators in my rented flat as winter is now starting to kick in and want things to work as efficiently as possible. Some advice says use a flat head screwdriver but there is not a groove in them to be able to use one. So I bought a radiator bleed key...
  14. JoeBilton

    Cold radiators balancing

    Our upstairs radiators were getting much hotter much quicker than down stairs. To try and balance I altered some of the lock values on the upstairs rads (not fully closed though) this seemed to work and the downstairs rads were much hotter however one of the upstairs rads was now totally cold...
  15. d36csr

    Installing smart TRVs on ALL radiators with use of a bypass valve

    Hi there, I recently bought a bunch of Drayton Wiser Smart TRV heads. I wanted to install them on all of my radiators so that I have full control of which radiators are on. However, it specifies in the instructions that one of the radiators should be left with 2 x open lockshield valves. Now...
  16. F

    Why can't I get Upstairs radiators to work independently

    Hi, wonder if anyone can give some advice. Recently moved into a new property. It has external OIL combi boiler which is new and works well. Downstairs has underfloor heating - which works well. Upstairs has wall radiators - which work well - but ONLY if the downstairs thermometer is calling for...
  17. D

    Radiators hot upstairs and cold downstairs

    I've a pressurised CH system with a combination vented cylinder. I live in a two story house with 4 radiators upstairs and 4 downstairs. I recently had the CH pressurised and the cylinder also was replaced. The problems is that the radiators upstairs are getting nice hot but the ones downstairs...
  18. B

    All radiators are getting hot when we've only got HW on.

    We've been the house for just over 2 years. We've only just got around to figuring out this 'Y' plan system as we've never had one before. We've been using the immersion tank for hot water (using the electrical backup ££££) since we moved in, but with costs rising, I need to figure out where the...
  19. J

    Radiators top half hot & bottom half cold/warm---to do power flush?

    Hi all, I had my new boiler and 13 radiators installed in July last year, but since installed all the radiators always top half hot and bottom half cold or warm. I know that if radiators top half hot bottom half cold/warm, it indicates there's sludge in the system. But as the radiators were all...
  20. C

    Please help me work out why my radiators aren't heating

    Hello all, Like most people, I've gone to turn on my central heating after 6 months of it being off and, surprise surprise, it doesn't work. I'm trying to work out what is wrong with it myself, I enjoy the challenge and the learning process; if all fails, I can call a plumber. I have an Ideal...
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