Step 1: Is the boiler on? Yes, it could be that simple!
Make sure that the boiler is on, the timer/programmer is set to heating and the room
thermostat and any radiator thermostatic valves are turned up so that the heating
system is asking the boiler to provide the radiators with hot water.
Step 2: Is the circulation pump running? If you have
a traditional heating system with a hot water cylinder then check that the circulation
pump is running.
The pump is usually in the airing cupboard and here's what it may look like:
If the boiler is on but the water in the pipes around the pump aren't warm, the pump
may be faulty.
If you have a combi or system boiler the pump will usually be incorporated in the
boiler itself, so check the pipes to and from the boiler to see if hot water is flowing
in and out of it. Be careful - the pipes can be very hot!
Step 3: Is the divertor valve stuck? If you have a traditional
heating system with a hot water cylinder then check that the diverter valve isn't
stuck. The diverter valve is usually in the airing cupboard and here's what it may
2 port heating valve
3 port heating valve
If the boiler is on and the pipe to the valve is warm but the one from it isn't, the
valve may be faulty.
You can test this by sliding the manual operation lever out of the automatic position
into the manual position to open the valve. Be careful -
the levers can be sharp and difficult to push, even on relatively new valves.
Step 4: Is the radiator valve stuck? If the diverter
valve and pump are working but the radiator isn't getting warm, check for heat in
the pipes running to and from the radiator.
If the pipes are warm, or one is warm and the other isn't, one or both of the radiator
valves could be turned off or faulty.
Try turning them on to the maximum setting (usually by turning the control knob anti-clockwise)
to open them.
And of course, if you are still having problems with your radiators after doing the
above, call us!
Step 5: Is the radiator full of air? Try bleeding the
radiator using a bleed key (available from most DIY and hardware stores).
radiator bleed key
radiator bleed valve
Place the key over the bleed pin in the bleed valve socket at the end/top/inside top
edge of the radiator and hold a cloth over it (to stop dirty water squirting
Slowly turn the bleed key anti-clockwise until the sound of air hissing is heard,
then hold the key in place until water comes out.
Finally, turn the key clockwise to close the bleed valve.
Step 6: Is the radiator full of black sludge? The simplest
test for black sludge in your radiators
is to check the temperature difference between the top and bottom of the radiators
in each room.
Once your heating has reached its normal operating temperature, using the back of
your hand (not the palm+) feel the temperature at the top-middle of the radiator and
then down at the bottom.
If the bottom of the radiator is noticeably cooler than the top then black
sludge is probably blocking the flow of hot water through the bottom of the radiator
and your heating system may need a PowerFlush.
+ Use the back of your hand rather than the palm to check
for radiator cold spots.
If the radiator is too hot, normally you will pull the back of your hand away by instinct,
but if you use your palm a spasm may cause you to grip the radiator and injure yourself.
Click on the image below for more signs of black
sludge in your heating system:
Image courtesy of Kamco Ltd
DripFix is an authorised Kamco stockist.