Heating System Trouble Shooter

At Harris Heating we realise that not all problems require an expert to solve them. So, put as simple as possible, we provide below a list of some typical problems - and possible solutions. Do please bear in mind that plumbing and heating systems can be dangerous - as they operate under relatively high water pressure using combustible fuel and electricity with carbon monoxide by-products.
If you think something may be wrong with your heating system, this section may help you solve the problem before you need to contact one of our engineers.

Please remember AT ALL TIMES that your safety, and that of your family, is vital. If you are in any doubt at anytime - do please contact us.

What is the problem?
      The top section of my radiator is cold
      The bottom section is cold or all radiators are cold or luke-warm
      Only the upstairs radiators are cold
      Only downstairs radiators are cold
      Radiators are cooler in one area of the house
      Radiators are warm upstairs when the heating is off, and the hot water is on
      There's no heating or hot water
      There's a sound of gurgling water
      I can hear humming
      I can hear knocks and creaking
      My boiler is noisy

Not sure what the problem is? Carry out some basic checks using the checklist below........

Is the electricity supply on?
Check that the boiler supply switch is lit/ on. Check the fuse on the boiler supply switch: replace if necessary.

Is the water pressure adequate?
Check the pressure gauge on the front panel shows 1.0-1.5 bar. If not, turn off the boiler - locate the filling loop tap and top-up to required pressure. If problem persists contact us.

If the boiler has a pilot light, is it lit?
No? Refer to manual for lighting procedure. Re-light pilot and observe. (Instructions may be printed on the reverse of the boiler front panel) Yes? but the main burner doesn't light. Check room thermostat and time clock are calling for heat.

Is the pilot light lit but there's no heating or hot water?
Yes? Could be due to pump or gas valve failure. Contact usfor assistance.

If the boiler has an electronic ignition (i.e. no pilot), is a spark present?
(Use eye-view to check inside the boiler) No? Contact us for assistance

Is the boiler particularly noisy?
Yes? Could be due to pump failure Contact us for assistance.

Conventional Boiler: Is there either hot water or central heating but not both?
Yes? Check the diverter value is functioning. Refer to manual for location of valve.

The top section of my radiator is cold...
This probably means the radiator needs 'bleeding'. To bleed your radiator:
Turn off the heat
Find the bleed valve, this is usually on one side near the top
Place a cloth underneath the bleed valve
Use a radiator key to gently release the valve and listen for the hiss of air
Tighten the valve as soon as water begins to flow, and use the cloth to clean up. Take care - the water can be very hot. Then switch the heat back on
If you find you need to bleed your radiators frequently, you may want to call a Harris Heating engineer - LO-CALL 1850 348 348 or contact us now.

The bottom section is cold or all radiators are cold or luke-warm
This probably means rust or sludge is obstructing the radiator. To clean this you will need to remove the radiator:
Turn off the heat
Protect the floor with cloths and have a spanner or pliers, a wrench and a few bowls ready
Close the valves at each end of the radiator and remove the plastic shield from the 'lockshield valve', closing it with the spanner or pliers.
Open the bleed valve near the top of the radiator to allow water to escape. If water keeps running the other valves are not closed properly.
Use the bowls to catch any water and undo the nuts holding the radiator to the valves on each end. You'll need to do this slowly.
Ask someone to help lift the radiator from its brackets
Drain any remaining water into the bowl
With the radiator upright, carry it outside
Stand the radiator on its end, flush out the sludge with a hosepipe before bringing it back in
Checking the brackets are secure, place the radiator back on the wall and reconnect the nuts
Open the valves to fill the radiator, then open the bleed valve to allow air to escape and reset the lockshield valve.

Only the upstairs radiators are cold
This may well mean the cistern in your loft has run dry, because of a jammed or obstructed ball valve. To fix the cistern:
Clear any obstruction or worn parts
Check there is enough water to make the ball float when the system is cold.

Only downstairs radiators are cold
It is likely that the pump is broken. You'll need to call out a Harris Heating engineer. Lo-Call 1850 348 348 or contact us now.

Radiators are cooler in one area of the house
This suggests the system is unbalanced. To balance it, you need a pair of radiator thermometers and then:
Turn off the heat, allowing the system to cool
Turn on the valves at each end of every radiator, remove the lockshield valve's plastic cover and turn it using pliers
Turn the heating back on, checking the order in which the radiators heat up
Starting with the first radiator, place a thermometer on the pipe at both ends
Turn off the lockshield valve and gradually turn it back on until there's almost no difference between the two thermometers
Repeat on the second radiator and every radiator in turn; when you've finished you'll have a balanced system.

Radiators are warm upstairs when the heating is off, and the hot water is on
If you have a gravity-fed system, the check valve is broken. You will need to call out a Harris Heating engineer.

There's no heating or hot water
These checks may help you fix the problem:
Check your power supply is working and a fuse hasn't blown
Check the gas hasn't been turned off or you have enough oil in your tank
Check your thermostats and control switches are turned on
Check the pump is running
Check the pilot light is lit, your boiler manual will tell you how to relight it
If none of this works, you'll need to contact us to arrange a heating engineer's examination of your heating system.

There's a sound of gurgling water
This probably means there's air in the system and the radiator needs 'bleeding'. Instructions for this can be viewed here.

I can hear humming
The pump usually causes these noises. These steps should solve the problem:
Lower the setting on the pump
Fit the pump on the brackets that absorb its vibrations
Check the pipes are the right size, to do this you may need to get in a Harris Heating engineer - contact us on line or Lo-Call 1850 348 348 NOW.

I can hear knocks and creaking
As pipes expand and contract they rub against joists and walls causing strange noises. To prevent these sounds:
Find out where the noise is coming from
Establish where the pipes are rubbing or don't have enough space
Widen the space around the pipe carefully using a saw or chisel. Too much space might weaken the pipe
You could use fibreglass insulation to cover the pipes
In some cases noise can come from unsupported pipes - so secure pipes with a lot of free movement using pipe clips

My boiler is noisy
Scale and sludge inside, restricted water flow, pockets of steam or even trapped air can cause a noisy boiler. In every case you'll need to call out a Harris Heating engineer to find the cause and repair the boiler. Call Lo-Call I850 348 348 or contact us on line right nowContact Us.

Home     Welcome     Area Covered     Why Choose HARRIS?     YOUR HOME & BER     Choosing a Contractor     Contact Us