An introduction to thermostatic radiator valves
You may well have heard the term ‘thermostatic radiator valve’ (TRV) without really knowing what they are or what they do. What is a TRV, how does it work, and how can it improve your heating system?
TRVs and how they work
Effective heating controls can help you to save money on heating your home. TRVs are part of controlling your system. Older installations have a thermostat in just one location that controls the temperature for the whole house while a TRV gives you control over the temperature of an individual room; for example, you can have the bedrooms cooler than the lounge.
A TRV works using a capsule that either expands or contracts depending on the temperature. This moves a pin that allows the valve to open or close, thus regulating the flow of water into the radiator.
You can fit TRVs to any type of radiator, whether you have column radiators from a specialist such as http://apolloradiators.co.uk/Products/View/3/54/7/category/roma/Apollo-roma-bespoke-steel-column-radiator or more conventional types. You should not, however, fit TRVs everywhere. Standard practice is to leave one radiator without a TRV, and it makes sense for this to be in the room in which your system room thermostat is located so that the two don’t conflict with each other.
Room thermostats are often located in the hallway. This is an area subject to lots of traffic from inside and out, with consequent changes to air flow, so it is hard to heat consistently anyway. It therefore makes sense not to have a TRV here.
Fitting TRVs will involve draining down the heating system. If you are contemplating doing so, it is worth doing the whole house in one go. This will be a day’s work for a heating engineer and will cost you a few hundred pounds.
TRVs can sometimes stick in the open or closed position, which is likely to happen after a summer when the radiators haven’t been on for a while. This is something you can often fix yourself by opening the valve to its fullest extent, then removing the top – you shouldn’t need tools to do this – and giving the pin a squirt of WD-40 so that it can move up and down freely. It is also important not to block the airflow to the valve with furniture or radiator covers.