Why are my radiators hot when the thermostat is off?

Radiators coming on when thermostat is off. If the anti gravity valve is broken or blocked and is not doing its job of stopping the natural convection process, it means heat will rise through your central heating system. Your radiators will be on, even though your thermostat is off.

Why do my radiators stay hot?





A check valve is used to stop the natural convection from warming up your home when your heating is switched off. If the check valve is broken or blocked, heat will rise through your system causing your radiators to stay hot. Once again, contact a qualified professional to come and check what the problem is.

Why are some radiators hotter than others?

Some radiators occationally get quite a bit warmer than others. When this happens it usually means that your central heating system is out of balance. In some instances, radiators can be different temperatures due to the distance that water that heats them has to travel from the boiler or pump.

How do you balance radiators with thermostatic valves?

Quote from the video:
Quote from Youtube video: So what you should do is go to the lock shield in the radiators upstairs. Close them and then open them about quarter.

Why does my boiler come on in the middle of the night?

It’s true that boilers do turn on from time to time during the night. Combi boilers work best when the heat exchanger inside is kept warm, so it will need “topping up” a few times overnight to make sure you have instant hot water when you need it.

How do I know if my thermostat is bad?





7 Ways to Tell Your Thermostat Is Broken

  1. Thermostat Has No Power. …
  2. AC or Furnace Won’t Turn On. …
  3. Heater or AC Won’t Turn Off. …
  4. Thermostat Doesn’t Match Room Temperature. …
  5. Thermostat Doesn’t Respond. …
  6. Short Cycling. …
  7. Thermostat Forgets Programmed Settings. …
  8. Thermostat Replacement Services.


How do I reduce the heat in my radiator?

Block Your Radiator’s Heat



The hotter a steam radiator gets, the more warmth it radiates. So covering it up with a blanket or sheet is a simple solution for limiting the amount of heat the radiator puts out into the room. Radiators use natural air convection to heat a room.

Why is my central heating getting too hot?

Faulty diverter valve



As the diverter valve open and closes countless times throughout the day, over a period of time it ca become clogged with debris and get stuck. It could be responsible for delivering too much hot water to your radiators and making them feel overly hot.

Why is my heating not turning off?



If your heater won’t turn off, the first thing you do is check the thermostat. The thermostat controls how the heating system runs. It detects the indoor temperature and signals the furnace to start or stop. So, if the thermostat malfunctions, it can signal the unit to run continuously.

How do I know if my radiators need balancing?

If you have hot and cold spots on some of your radiators or find that some radiators get warm whilst others do not, then your radiators need balancing.

Why are some radiators hot and some cold?

If your radiator is hot at the top but cold at the bottom, there may be a build-up of scale, rust, or sludge which is obstructing the flow of water. As with the middle of the radiator, if you have an open-vent system which is unpressurised and tank fed, you’ll be able to use a sludge remover to flush your radiator.

What should radiator thermostats be set at?



As a rule of thumb most guidelines recommend heating your home to 70F (21C) and bedroom temperatures should be kept a little cooler to around 64F (18C). For most people this temperature will be comfortable, but if it feels a little hot (or alternatively cold) then the temperature can be adjusted from this baseline.

Why does my combi boiler keep firing up when heating is off?

If your combi boiler fires up then turns off, this is likely to be the ‘preheat’ function. This is nothing to worry about and simply ensures there’s some hot water ready to be sent to the taps when you need it.

What temperature should I leave my heating on overnight?

A better idea: Turn the heat down, not off



Here’s the secret: Set the temperature of your home at least eight degrees lower for the eight hours or so that you sleep at night. Every degree you lower the thermostat can net you an estimated 1% off your heating bill.

Why does my boiler come on when I run cold water?

There is an air bubble trapped in the water pipes the change in pressure causes a bounce which tricks the combi boiler into firing up. Often cured by running the taps to shift the air lock. need a mini shock arrestor and non return valve installed onto the cold feed going into boiler that will resolve the problem.

Do washing machines use hot water from the boiler UK?



Newer machines



Modern machines are being manufactured to eco-friendly standards (see the most economical washing machines in the UK here), so will only use the cold supply. Only using water from the cold supply is said to save you money in the long run by not using your heating system.

How often should my boiler fire up?

It should do it once every hour or two, and each time will last a couple of minutes. Again, this is perfectly normal, so you don’t need to do anything. If it’s turning on regularly then turning off, and doing this repeatedly, that’s more likely to signal a fault.

Does cold water go through boiler?

Cold water from the mains will pass through the boiler where it’s heated up and then travels through the pipes to either the radiators, tap or shower. Unlike system and regular boilers, there are no cylinders or tanks. Combi boilers will heat up and deliver hot water instantly as and when needed.

Do you bleed a radiator when it is on or off?

Turn off your heating. You can’t bleed a radiator when the heating is on, as it may be too hot to touch. You could also get hot water spraying out of the radiator. Use your radiator key to turn the valve at the top of the radiator.

Do you leave a combi boiler on all the time?



First and foremost, don’t keep the central heating on all the time. Instead, set the heating to only come on as and when you need it. The domestic hot water, on the other hand, can be kept on all the time, as combi boilers provide this to taps and showers on demand.