hiya bucks in Bourne End, Flackwell Heath, Marlow, Wycombe, Wooburn January 2014 | Page 8

regular feature

The 50plus
fixing a failed
radiator
It’s that time of year,
central heating now
well and truly on and
a radiator fails. There
are two common
causes.
1. Air in the radiator
Bleed the radiator. If air is
released then keep going
until water is let out of the
bleed valve. The radiator
should then rapidly heat up.
2. A faulty thermostatic valve
If the radiator has a
thermostatic valve then check
to see if the pin is stuck and if
it can be freed. This is usually
a simple job and well within
most homeowner’s capability.
The trick is to know how the
valve works.
Thermostatic valves operate by using gas
or liquid filled bellows in the valve head.
The gas expands as the room temperature
rises, causing the sprung pin in the body
to be depressed which restricts the water
flow through the radiator. Turning the
valve head alters the distance between
the bellows and the pin, thereby altering
the room temperature at which the valve
actuates.
The pin itself can stick, particularly after
a period of inactivity such as the summer
months. Frequently a repair is possible
8

without having to change the valve.
Firstly remove the valve head by
unscrewing the retaining ring (located
at the base of the valve head and the
large chrome ring in the picture) and
thus exposing