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Posts tagged radiators

T.R.V.’s – What Are they And How They Can Save You Money

Thermostatic Radiator Valve

On your radiator you should have something similar to the picture above. These are called T.R.V.’s or Thermostatic Radiator Valves.

T.R.V.’s are self regulating valve fitted to the radiators on a heating system. Traditionally, they have a wax plug which expands and contracts with the temperature around the valve. The plug is connected to a pin,which is connected to a valve. As the temperature around the valve increases, the pin decreases the flow of water through the valve thus allowing a maximum temperature for each radiator to be set.

T.R,V.’s can dramatically decrease the amount of fuel your household burns and thus save you a substantial amount of money as well as providing a comfortable temperature in your individual rooms.

But they must be set correctly to achieve this. Luckily this is an easy process.

  • Step 1 – Make sure your room thermostat is turned up to around 20 degrees
  • Step 2 – Turn every T.R.V. to setting 4 out of 5 (or equivalent) and turn on your heating system
  • Step 3 – Turn down 1 /2 a notch (setting) of the T.R.V.(s) of the room you are in. Give it approximately half an hour and if you are not cold, turn down another 1/2 a notch . Repeat this process until you feel a bit nippy.then turn up 1/2 a notch.
  • Step 4 – Repeat this process in each room. Remember that, you need to take into account what you would typically be doing in each room when setting the T.R.V.’s. i.e. sitting in armchair in your lounge, bathing in the bathroom so try to recreate this when setting the valve.


Note. I said it was an easy process, not quick, you may have to do this over a few days/week. You may also have disagreements with partners, housemates and pets as to what is cold and what is hot. The management take no responsibility for any disputes that arise from following this advice…

Bleeding Air Inside Oil-fired Heating System Radiators

Bleeding a radiator is a fairly straight forward maintenance job, something you can do yourself with just a few tools. Read through the instructions and get your tools together before starting. If you have any doubt or lack the required tools then please feel free to contact us

Step 1

Turn your heating on and wait for the radiators to get hot. This will help you determine which radiators require bleeding. Those with ‘cool spots’  or that don’t heat at the top will be the ones you need to concentrate on.

Step 2

Turn off the heating. Wait awhile until things cool down a little.

Step 3

To bleed the radiators you will need a good quality radiator key such as the one below.

good-radiator-bleed-keyDo not use the style shown below.



Lay down a sheet or towel under the radiator where you are working.

At the top of the radiator on one end is the radiator vent. You need to attach the radiator key to the square bit at the centre of the valve or insert the flat ended part of the screwdriver into the groove.

Keep a clean cloth in one hand near to the vent, hold the key or screwdriver and slowly turn anti-clockwise. you should start to hear a hissing sound, this is the air escaping.

Once water starts to escape, close the vent by turning the key or screwdriver clockwise.

Do not fully unscrew the radiator vent grub screw! If the valve itself starts to turn, tighten it up and then hold it in place with a spanner.

Step 4

If you have a combi or system boiler or your heating system is pressurised, you may need to ‘top up’ the water pressure in your heating system.. You can do this with the relevant taps at the boiler or the lever valves at your filling loop. (please refer to boiler manufacturers instructions).

Tackling cold or luke warm radiators on Oil-fired heating systems

The first thing to determine is where the radiator is cold. This will help to identify where the problem is…

Radiator cold at the top

The top being cold indicates that air has been trapped in the radiator. This can be remedied by bleeding the radiator. (See my other home help). Note, air in the system can be a symptom of an underlying problem which may need to be addressed.

Radiator cold at the bottom

If the radiator is cold at the bottom, then the likely cause is ‘sludge’. This would require the radiator and more than likely the heating system to be cleaned. This can be done chemically and/or manually. A cleanser is added to the system for between 2 hours and 2 weeks and the system rinsed through. Occasionally, the radiator may need to be taken off and flushed through manually with mains pressure water.

If the sludge build up is particularly bad, then the heating system will need to be ‘power-flushed’. Note, whenever water is drained from the heating system, it will need a suitable amount of system inhibitor added to ‘top up’.

Radiator completely cold

If the radiator is completely cold, then then the valves may be turned off or stuck or you may have an air lock somewhere in the system. This may warrant inspection by a qualified professional.