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Discuss Gas central heating - confused as how best to work it & why rads cool off when on?! in the Central Heating Forum area at

  1. Mandy Cowlishaw

    Mandy Cowlishaw New Member

    I’ve recently moved to a new house which has gas central heating and I’m confused as to how it works!

    So when I first switched the system on, all the rads, except for one got hot.

    The main thermostat control is located in our hallway and is set to 21 degrees. However every now and then I feel each of the rads and they all feel different temperatures. For instance our lounge and dining room are adjoined but open planned but even though both rads in each of those rooms are set to the same number on the rads, one is much hotter than the other, but I cannot understand why as it doesn’t feel like the two rooms are different temperatures.
    The rads’ heat are also consistent at the top and bottom so I don’t think they need bleeding.

    When I turn the thermostat in the hallway down to a much lower temperature it clicks which i think means the hall hasn’t yet reached the correct temperature?

    So my question is if if the room hasn’t reached the temperature set on the thermostat shouldn’t that rad stay hot until it does?

    And is it more efficient to leave the heating on relying on the thermostat, or is it ok to switch the whole system off from the main timer when we are warm enough and just turn it back on when it gets cold again..which is what i have been doing?

    Any help would be much appreciated!
  2. king of pipes

    king of pipes Trusted Plumber GSR

    Your boiler should heat all your radiators equally if installed and sized correctly, radiators fail to operate to their correct output when more than one is supplied from the same feed pipework meaning the first radiator steals all the heat that the pipework can supply leaving the other feeling cooler, I recommend my customers keep their homes thermostat set to 18 degrees c when in standby and 21 - 22 degrees c when occupied. Kop
    • Like Like x 1
  3. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    trvs set differently ?
    • Informative Informative x 1
  4. Chalked

    Chalked Plumber GSR

    Easy answer.
    Never feel,the rads. Feel the temperature in the room ( air).
    If that fee
    S right , then the room thermostat and radiator thermostats are doing their job.
    When two rads are in one room, you always get a lead and lag.
    • Agree Agree x 2
    • Like Like x 1
  5. gmartine

    gmartine GSR

    My elderly ma does the same, gives me a call and says the CH isn't working and the rads are cold. Go round there and get hit by a heat blast as I walk through the front door.
    • Like Like x 2
    • Funny Funny x 2
  6. Best

    Best Trusted Plumber

    Could also be a balancing issue, although feeling by your hand a difference in heat means there is a dramatic difference.
    I would first assume the TRVs are shutting down at different rates.
    Keep an open plan radiators at same number on their TRVs.
    I had to tell my partner that when I discovered she was trying to save gas by turning on radiator in an open plan area lower than the other.
    As had been said, just check if room temperature is reached, and ignore if rads go hot and cold
    • Like Like x 1
  7. Mandy Cowlishaw

    Mandy Cowlishaw New Member

    Yes they are...the downstairs ones are all set to 3 and upstairs are set at 2
  8. Best

    Best Trusted Plumber

    Try the TRV setting on downstairs rads a little higher. Number 3 setting is very low. Try 3.5 or 4
  9. dan_the_plumber

    dan_the_plumber GSR

    Balancing issue
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