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Troubleshooting. Find the fault, one question at a time.

Answer one question at a time to narrow down the likely cause, the fix, and when to stop and call an engineer. Covers air conditioning, heat pumps, boilers and home appliances.

Safety first. Isolate the power before removing filters or covers. In the UK only F-gas certified engineers may work on refrigerant circuits, and only Gas Safe registered engineers may work on gas appliances. If you smell gas, call the National Gas Emergency line on 0800 111 999.

Heating & cooling

Appliances

A guide only, written by Tradefox. Always follow the manufacturer's instructions and stop if you're unsure.

All troubleshooting guides

Every question and outcome in each guide, written out in full. Open a guide to follow it on paper, or choose a problem above to step through it one question at a time.

Air conditioner not cooling 7 questions, 8 outcomes

Running, but the room isn't getting cooler.

  1. Is the indoor unit running and blowing air?

  2. Is the controller set to Cool mode with a set temperature at least 2-3 C below the room temperature?

    Auto or Dry mode, or a set point close to room temperature, can look like 'not cooling'.

  3. Outcome: Unit isn't running

    Likely cause: The unit has no power, is switched off by the controller, or has a fault stopping it.

    What to do:

    1. Use the 'Unit won't start' guide in this tool.

  4. When did you last clean the indoor filters?

  5. Outcome: Settings issue

    Likely cause: The unit is in the wrong mode or the set point is too high, so it isn't calling for cooling.

    What to do:

    1. Select Cool mode, lower the set temperature, set fan to Auto, and wait 10-15 minutes.

  6. Is the outdoor unit's fan running?

  7. Outcome: Blocked filters

    Likely cause: Dirty filters starve the coil of air, so cooling capacity drops and the coil may ice.

    What to do:

    1. Isolate power, remove and wash the filters in lukewarm water, let them dry and refit.
    2. Clean every 2-4 weeks in heavy use.

  8. Is the outdoor coil clean and clear of leaves, plants or anything within ~30 cm?

  9. Is there an error code or flashing light on the indoor unit?

  10. Is there frost or ice on the indoor coil or the pipework at the outdoor unit?

  11. Outcome: Outdoor airflow restricted

    Likely cause: The outdoor unit can't reject heat, so cooling capacity falls and pressures rise.

    What to do:

    1. Isolate power, clear debris and cut back vegetation.
    2. Gently rinse the coil from the inside outwards with low-pressure water if the manual allows.

  12. Outcome: Fault code present

    Likely cause: The system has detected a fault and stopped the outdoor unit.

    What to do:

    1. Look up the code in the HVAC error code tool.
    2. Power-cycle at the isolator once; if it returns, book an engineer.

    Stop here: call a competent engineer.

  13. Outcome: Outdoor unit not running

    Likely cause: Possible causes: outdoor isolator off, failed fan/compressor, capacitor or board fault.

    What to do:

    1. Check the outdoor isolator switch is on.
    2. Do not remove covers - mains voltage and stored charge inside.
    3. Book an air-conditioning engineer.

    Stop here: call a competent engineer.

  14. Outcome: Icing

    Likely cause: Usually low airflow; repeated icing with clean filters points to low refrigerant charge.

    What to do:

    1. Switch to Fan-only for 1-2 hours to defrost.
    2. Use the 'Iced evaporator' guide.
    3. If it re-ices with clean filters, an F-gas engineer must check the charge.

    Stop here: F-gas certified engineer required.

  15. Outcome: Likely refrigerant or component fault

    Likely cause: Airflow and settings are fine, so the likely causes are low refrigerant (a leak), a faulty valve or a weak compressor.

    What to do:

    1. Note any error codes and the age of the system.
    2. Do not attempt to re-gas: only F-gas certified engineers may handle refrigerant.
    3. Book an F-gas certified engineer to leak test and check pressures.

    Stop here: F-gas certified engineer required.

Heat pump not heating 9 questions, 9 outcomes

Radiators, underfloor or wall units not warming up.

  1. Is it an air-to-water heat pump (radiators/underfloor) or air-to-air (wall units)?

  2. Is there an error code on the controller?

  3. Is the unit in Heat mode with a set point above room temperature?

  4. Outcome: Fault code present

    Likely cause: The heat pump has detected a fault.

    What to do:

    1. Look up the code in the HVAC error code tool.
    2. Note it and contact your installer if it persists.

    Stop here: call a competent engineer.

  5. What does the system pressure gauge read (cold)?

  6. Does the indoor unit stop blowing for a few minutes and then restart, with steam rising from the outdoor unit?

  7. Outcome: Settings issue

    Likely cause: Wrong mode or set point.

    What to do:

    1. Select Heat mode and raise the set point.
    2. Allow 5-10 minutes - the indoor fan waits until the coil is warm (hot start) to avoid blowing cold air.

  8. Outcome: Low system pressure

    Likely cause: Low pressure trips the heat pump's flow/pressure protection.

    What to do:

    1. Use the 'Low pressure' guide in this tool to top up.
    2. If pressure keeps dropping, there's a leak or a failing expansion vessel.

  9. Is hot water working but heating not?

  10. Outcome: Normal defrost

    Likely cause: In cold, damp weather the outdoor coil frosts and the unit periodically reverses to clear it.

    What to do:

    1. This is normal. Make sure meltwater can drain away and the unit isn't sitting in snow.

  11. Are the filters clean and the outdoor unit clear of debris/snow?

  12. Outcome: Diverter valve / heating demand

    Likely cause: The heat pump runs but heat isn't reaching the heating circuit - often a stuck 3-port diverter valve, a zone valve, or the thermostat/schedule not calling for heat.

    What to do:

    1. Check the heating schedule, room thermostat and that heating mode is enabled.
    2. Check zone valves are open.
    3. Engineer to test the diverter valve actuator.

    Stop here: call a competent engineer.

  13. Is the outdoor fan and compressor running (hum, fan turning)?

  14. Outcome: Needs an engineer

    Likely cause: Likely compressor, fan, sensor or control fault.

    What to do:

    1. Note any codes and when it started.
    2. Refrigerant work must be done by an F-gas certified engineer.

    Stop here: F-gas certified engineer required.

  15. Outcome: Airflow restriction

    Likely cause: Blocked filters or a blocked outdoor coil cut heating output.

    What to do:

    1. Isolate, clean filters, clear the outdoor unit and retry.

  16. Are radiators lukewarm rather than cold?

  17. Outcome: Normal low-temperature operation or weather compensation set too low

    Likely cause: Heat pumps run at lower flow temperatures; radiators feel warm, not hot. If rooms aren't reaching temperature, the heating curve may be too low.

    What to do:

    1. Leave heating on steady rather than boosting.
    2. Ask your installer to raise the weather compensation curve slightly.

  18. Outcome: Poor circulation

    Likely cause: The heat pump runs but water isn't circulating: closed valves, air, a blocked filter or pump fault.

    What to do:

    1. Check isolation valves are open and clean the system filter.
    2. Bleed radiators.
    3. Engineer to check the pump.

    Stop here: call a competent engineer.

Unit won't start (AC / heat pump) 6 questions, 8 outcomes

No lights, no response, or it stops straight away.

  1. Does the indoor unit or controller show any lights or display?

  2. Does the remote control work (try new batteries; does the indoor unit beep)?

  3. Has the breaker/RCD for the unit tripped, or is the fused spur/isolator off?

  4. Is a timer, schedule, or central/external control (e.g. window contact, BMS) active?

  5. Outcome: Remote controller issue

    Likely cause: Flat batteries, wrong mode, or a failed remote/receiver.

    What to do:

    1. Fit new batteries and point at the receiver.
    2. Use the unit's manual ON/emergency button to test.

  6. Does it trip again immediately when you reset it?

  7. Outcome: No power at unit

    Likely cause: Power is on at the board but not reaching the unit - fuse, wiring or PCB fault.

    What to do:

    1. Check the fuse in any fused spur (isolate first).
    2. Otherwise call an engineer.

    Stop here: qualified electrician required.

  8. Outcome: Check the supply

    Likely cause: Most no-display faults are a tripped breaker or switched-off isolator.

    What to do:

    1. Check the consumer unit for a tripped breaker/RCD labelled for the AC/heat pump.
    2. Check the isolator next to the outdoor unit and any fused spur indoors.

  9. Outcome: Control is blocking start

    Likely cause: A schedule, timer or interlock is holding the unit off.

    What to do:

    1. Cancel the timer/schedule or close the window contact and retry.

  10. Is an error code or flashing LED shown?

  11. Outcome: Electrical fault

    Likely cause: An immediate trip means an earth fault or short circuit.

    What to do:

    1. Leave it off. Do not keep resetting.
    2. Call a qualified electrician / AC engineer.

    Stop here: qualified electrician required.

  12. Outcome: Supply restored

    Likely cause: A one-off trip (storm, surge). Monitor it.

    What to do:

    1. If it trips again, have it investigated.

  13. Outcome: Fault code

    Likely cause: The unit has a fault that prevents starting.

    What to do:

    1. Look the code up in the HVAC error code tool and follow the safety level shown.

    Stop here: call a competent engineer.

  14. Outcome: Restart delay or board fault

    Likely cause: Inverter units wait about 3 minutes before restarting the compressor. If it never starts, the board may be faulty.

    What to do:

    1. Wait 5 minutes.
    2. Power-cycle at the isolator for 5 minutes.
    3. If still dead, call an engineer.

    Stop here: call a competent engineer.

Iced-up indoor coil (evaporator) 4 questions, 4 outcomes

Frost or ice on the indoor coil or pipework.

  1. Switch the unit to Fan-only. Is it iced on the coil, the pipes, or both?

    Never chip ice off - you can puncture the coil.

  2. Are the filters dirty?

  3. Outcome: Low airflow from dirty filters

    Likely cause: Low airflow lets the coil drop below freezing.

    What to do:

    1. Let it fully defrost on Fan-only (1-2 hours).
    2. Clean filters, then retry in Cool.

  4. Is the fan speed on the lowest setting or 'quiet' mode, with the set point very low (e.g. 16 C)?

  5. Outcome: Operating conditions

    Likely cause: Low fan speed plus a very low set point, especially when it's cool outside, can freeze the coil.

    What to do:

    1. Use Auto fan and a set point of 21-24 C.

  6. Is the indoor fan actually turning normally?

  7. Outcome: Probable low refrigerant charge

    Likely cause: With clean filters and normal airflow, icing points to a refrigerant leak or a restriction.

    What to do:

    1. Leave it off.
    2. Only an F-gas certified engineer may leak test, repair and recharge the system.

    Stop here: F-gas certified engineer required.

  8. Outcome: Indoor fan fault

    Likely cause: No airflow across the coil.

    What to do:

    1. Isolate and book an engineer to check the fan motor and board.

    Stop here: call a competent engineer.

Water leaking from indoor unit 6 questions, 6 outcomes

Dripping from the wall unit, cassette or ducting.

  1. Isolate the unit. Is water dripping from the unit itself (rather than a pipe joint or wall)?

  2. Was there ice on the coil recently?

  3. Outcome: Leak from pipework/wall

    Likely cause: Could be condensate pipe joints, uninsulated refrigerant pipe sweating, or a building leak.

    What to do:

    1. Check insulation on pipework is complete.
    2. Ask an engineer to check the condensate pipe route.

    Stop here: call a competent engineer.

  4. Outcome: Ice melt overflowing the tray

    Likely cause: Melting ice can overwhelm the drain tray.

    What to do:

    1. Use the 'Iced evaporator' guide to find the cause.

  5. Does the unit have a condensate pump (usually a small box near the unit, hums when running)?

  6. Is the pump running and is its reservoir/float clean?

  7. Does the drain pipe outside run continuously downhill, unblocked, with its end clear (not under water/ice)?

  8. Outcome: Condensate pump fault

    Likely cause: A failed or clogged pump lets the tray overflow.

    What to do:

    1. Isolate. Clean the reservoir and float of slime if accessible.
    2. Replace the pump if it doesn't run (engineer).

    Stop here: call a competent engineer.

  9. Is the indoor unit level (or tilted slightly to the drain side)?

  10. Outcome: Blocked or badly-falling drain

    Likely cause: Algae, insects or a back-fall stop condensate draining.

    What to do:

    1. Clear the outlet end; flush with a little water.
    2. Engineer can clear the line with a pump/vacuum and correct the fall.

  11. Outcome: Blocked tray or cracked drain pan

    Likely cause: Slime or debris in the tray outlet, or a damaged tray.

    What to do:

    1. Book an engineer to clean the coil and drain tray (often part of an annual service).

    Stop here: call a competent engineer.

  12. Outcome: Unit not level

    Likely cause: Water collects at the wrong end of the tray.

    What to do:

    1. Engineer to re-level the mounting plate.

    Stop here: call a competent engineer.

Noisy outdoor unit 2 questions, 6 outcomes

Rattling, grinding, hissing or squealing.

  1. What kind of noise?

  2. Is anything touching the casing - pipes, wall, debris, loose panel screws or anti-vibration feet?

  3. Outcome: Fan blade striking something

    Likely cause: Ice, debris or a damaged fan/motor bearing.

    What to do:

    1. Isolate immediately.
    2. Clear debris/ice from outside the guard only.
    3. If it persists, engineer to replace fan or motor.

    Stop here: call a competent engineer.

  4. Outcome: Defrost or valve switching

    Likely cause: A brief hiss/whoosh and steam is normal during defrost or mode change.

    What to do:

    1. No action needed unless it is constant.

  5. Outcome: Start failure

    Likely cause: Repeated clicks without starting may be a contactor, capacitor or compressor fault.

    What to do:

    1. Isolate and call an engineer - capacitors can hold a dangerous charge.

    Stop here: call a competent engineer.

  6. Outcome: Worn fan motor bearing

    Likely cause: Bearing wear causes squeal that worsens over time.

    What to do:

    1. Book an engineer before the motor seizes.

    Stop here: call a competent engineer.

  7. Outcome: Loose panel or contact

    Likely cause: Vibration from loose screws or pipes touching.

    What to do:

    1. Isolate power, clear debris, tighten external panel screws.
    2. Ask an engineer to re-clip pipes or replace worn anti-vibration mounts.

  8. Outcome: Compressor/internal vibration

    Likely cause: Internal mounts or pipe clips may have worn.

    What to do:

    1. Book an engineer.

    Stop here: call a competent engineer.

Short cycling (starts and stops frequently) 4 questions, 5 outcomes

Keeps switching on and off every few minutes.

  1. How long are the run times?

  2. Is the thermostat/controller sensor near a heat source, draught, or in direct sun?

  3. Outcome: Probably normal modulation

    Likely cause: Inverter systems ramp up and down and may stop when the set point is reached.

    What to do:

    1. No action needed if rooms stay comfortable.

  4. Outcome: Poor sensor location

    Likely cause: The controller sees a false temperature and switches on/off rapidly.

    What to do:

    1. Move the thermostat or use the remote's own sensor setting.
    2. Engineer can fit a remote sensor.

  5. Is it a heat pump on radiators/underfloor with many zones or TRVs closed?

  6. Outcome: Too little system volume / flow

    Likely cause: When most zones are closed the heat pump can't shed its minimum output and cycles.

    What to do:

    1. Open TRVs fully in main rooms and let the heat pump control temperature.
    2. Installer may add a buffer or adjust minimum flow/hysteresis settings.

    Stop here: call a competent engineer.

  7. Are the filters clean and is the outdoor coil clear?

  8. Outcome: Possible oversizing, charge or control fault

    Likely cause: Short cycling with good airflow suggests an oversized unit, refrigerant problem or sensor/control fault.

    What to do:

    1. Record run/off times and any codes.
    2. Book an engineer; refrigerant checks require F-gas certification.

    Stop here: F-gas certified engineer required.

  9. Outcome: Airflow causing pressure trips

    Likely cause: Restriction drives pressure/temperature protection cut-outs.

    What to do:

    1. Clean filters and the outdoor coil, then monitor.

Boiler / heat pump low pressure 4 questions, 6 outcomes

Pressure gauge reading too low, or too high.

  1. Read the gauge with the system cold. What does it show?

  2. Do you know where the filling loop is and how to use it (see your boiler/heat pump user manual)?

  3. Outcome: Pressure is fine

    Likely cause: 1-2 bar cold is the usual range (check your installer's label).

    What to do:

    1. If a pressure code persists, the sensor may be faulty - book an engineer.

    Stop here: call a competent engineer.

  4. Outcome: Pressure too high

    Likely cause: Overfilled, filling loop left open, or a failed expansion vessel/plate heat exchanger.

    What to do:

    1. Check the filling loop valves are closed.
    2. Bleeding a radiator lowers pressure - stop when it's around 1.5 bar.
    3. If it keeps rising, call an engineer (Gas Safe for gas boilers).

    Stop here: Gas Safe registered engineer required.

  5. After topping up, does pressure fall again within days?

  6. Outcome: Top up guidance

    Likely cause: The filling loop is usually a braided hose or key under the boiler/cylinder with two valves.

    What to do:

    1. Switch the boiler/heat pump off.
    2. Open both filling-loop valves slowly and watch the gauge; close them at about 1-1.5 bar.
    3. Make sure both valves are fully closed afterwards.
    4. Reset the appliance as the manual describes.

  7. Can you see any drips at radiator valves, pipe joints, or water from the pressure-relief pipe outside?

  8. Outcome: Fixed

    Likely cause: Pressure loss was probably from bleeding radiators.

    What to do:

    1. Keep an eye on the gauge for a couple of weeks.

  9. Outcome: Leak

    Likely cause: A visible leak or discharging relief valve.

    What to do:

    1. Place a container under drips; tighten radiator valve glands gently if you're confident.
    2. A dripping relief pipe means the relief valve or vessel needs attention - call an engineer (Gas Safe for gas boilers).

    Stop here: Gas Safe registered engineer required.

  10. Outcome: Expansion vessel or hidden leak

    Likely cause: Common causes: flat expansion vessel, failing relief valve, or a hidden leak under floors.

    What to do:

    1. Book an engineer (Gas Safe registered for gas boilers) to recharge the vessel and test the relief valve.

    Stop here: Gas Safe registered engineer required.

Fridge not cooling 6 questions, 7 outcomes

Warm inside, or not as cold as it should be.

  1. Is the interior light on and the display working?

  2. Is the temperature setting correct (fridge 3-5 C, freezer -18 C) and holiday/demo mode off?

  3. Outcome: No power

    Likely cause: Socket, plug fuse or appliance fault.

    What to do:

    1. Test the socket with another appliance.
    2. Check/replace the plug fuse (usually 13 A - check the rating plate).
    3. If still dead, call an engineer.

  4. Is the freezer cold but the fridge warm?

  5. Outcome: Settings

    Likely cause: Wrong setting or demo/holiday mode.

    What to do:

    1. Correct the setting and wait 24 hours.
    2. Check the manual for how to exit demo mode.

  6. Is there a build-up of ice on the back panel inside the freezer (frost-free models)?

  7. Can you hear the compressor running and feel warmth at the back/sides?

  8. Outcome: Defrost system fault

    Likely cause: Ice blocks the airflow from freezer to fridge; the defrost heater, sensor or timer may have failed.

    What to do:

    1. Manually defrost (unplug with doors open, towels down, 24 hours) as a temporary fix.
    2. If it re-ices within weeks, an engineer should check the defrost system.

    Stop here: call a competent engineer.

  9. Outcome: Air fan or damper fault

    Likely cause: Cold air isn't being moved to the fridge.

    What to do:

    1. Check vents inside aren't blocked by food.
    2. Engineer to test the fan and damper.

    Stop here: call a competent engineer.

  10. Do the door seals close fully, and is there 5-10 cm space around for ventilation?

  11. Outcome: Compressor not starting

    Likely cause: Could be the start relay, thermostat, control board or compressor.

    What to do:

    1. Unplug for 10 minutes and retry.
    2. If still silent, call an appliance engineer.

    Stop here: call a competent engineer.

  12. Outcome: Possible sealed-system fault

    Likely cause: Compressor runs but no cooling suggests refrigerant loss or blockage.

    What to do:

    1. Move food to a cool box.
    2. Sealed refrigeration system repairs must be done by a qualified refrigeration engineer (F-gas certified where required).

    Stop here: F-gas certified engineer required.

  13. Outcome: Seals or ventilation

    Likely cause: Warm air entering or heat not escaping.

    What to do:

    1. Clean seals; test with a sheet of paper - it should grip.
    2. Pull the appliance out to allow airflow and vacuum the condenser coil (unplug first).

Washing machine not draining 5 questions, 7 outcomes

Water left in the drum after a cycle.

  1. Switch off and unplug. Is there an error code (e.g. OE, 5E, E20, F05, E18)?

    Water may be hot if a hot wash was running - let it cool.

  2. Outcome: Drain fault code

    Likely cause: The machine timed out waiting for water to drain.

    What to do:

    1. Look the code up in the appliance error code tool, then continue below.

  3. Have you emptied and cleaned the pump filter (usually behind a small door at the bottom front)?

  4. Is the drain hose kinked, squashed behind the machine, or pushed more than ~15 cm into the standpipe?

  5. Outcome: Clean the pump filter

    Likely cause: Coins, hair grips and fluff often block the filter.

    What to do:

    1. Put towels and a low tray down.
    2. Drain via the small emergency hose (if fitted), then unscrew the filter slowly.
    3. Clean it, check the impeller turns, refit tightly.

  6. Outcome: Hose problem

    Likely cause: A kinked or poorly positioned hose restricts or siphons water.

    What to do:

    1. Straighten and re-route the hose; secure the U-hook at the correct height.

  7. Was the machine recently installed or a new sink trap fitted?

  8. Outcome: Blanking disc in new waste spigot

    Likely cause: New sink traps have a sealed disc on the spigot.

    What to do:

    1. Remove the hose and cut/punch out the blanking disc.

  9. Does the pump hum or run when you select a Drain/Spin programme?

  10. Outcome: Pump jammed or failing

    Likely cause: Debris in the impeller or a worn pump.

    What to do:

    1. Recheck the filter housing for debris.
    2. Otherwise replace the pump (engineer).

    Stop here: call a competent engineer.

  11. Outcome: Pump or control fault

    Likely cause: Pump motor, wiring or board not driving the pump.

    What to do:

    1. Book an appliance engineer.

    Stop here: call a competent engineer.

  12. Outcome: Blocked waste

    Likely cause: The house waste or trap is partly blocked.

    What to do:

    1. Clear the sink trap/standpipe; check whether the sink also drains slowly.

Dishwasher not draining 4 questions, 5 outcomes

Water sitting in the bottom of the tub.

  1. Switch off. Is there water sitting in the bottom of the tub?

  2. Have you removed and cleaned the filter assembly in the base?

  3. Outcome: Draining OK

    Likely cause: A little water around the sump is normal.

    What to do:

    1. If dishes are dirty, check spray arms and filters.

  4. Under the filter, is there a pump cover you can lift - is the impeller free (check for glass/stones)?

    Wear gloves - broken glass is common here.

  5. Outcome: Blocked filter

    Likely cause: Food debris and glass blocks the filter.

    What to do:

    1. Twist out the filter, wash it under the tap, scoop water from the sump and refit firmly.

  6. Is the drain hose kinked, or is the sink waste/trap or a new spigot blocked?

  7. Outcome: Pump obstructed

    Likely cause: Debris jams the drain pump impeller.

    What to do:

    1. Remove the pump cover per the manual, clear debris with a spoon, refit.

  8. Outcome: Hose or waste blockage

    Likely cause: Restricted outlet.

    What to do:

    1. Straighten the hose, clear the trap, remove any blanking disc on a new spigot.

  9. Outcome: Pump or control fault

    Likely cause: Filters and hose clear but still no drain.

    What to do:

    1. Book an appliance engineer.

    Stop here: call a competent engineer.

Electric oven not heating 4 questions, 6 outcomes

Not getting up to temperature, or not at all.

  1. Is it a gas or electric oven?

  2. Outcome: Gas oven

    Likely cause: Gas ovens involve ignition and flame-safety devices.

    What to do:

    1. Check other gas appliances work and the clock/timer is set (some won't run until set).
    2. If you smell gas: turn off the supply, open windows, don't use switches, call 0800 111 999 (UK).
    3. Any repair must be done by a Gas Safe registered engineer.

    Stop here: Gas Safe registered engineer required.

  3. Is the display/clock on?

  4. Is the clock flashing, or is a child lock / demo mode / timer set?

  5. Outcome: No power

    Likely cause: Cooker isolator or breaker off, or a supply fault.

    What to do:

    1. Check the cooker switch and the consumer unit breaker.
    2. Cookers are usually hard-wired - any wiring work must be done by a qualified electrician.

    Stop here: qualified electrician required.

  6. Outcome: Clock or lock not set

    Likely cause: Many ovens won't heat until the time is set or locks are off.

    What to do:

    1. Set the clock and clear locks/timers as per the manual.

  7. Which part isn't heating?

  8. Outcome: Fan oven element or fan

    Likely cause: The circular fan element or fan motor has likely failed.

    What to do:

    1. Isolate the oven. Book an engineer to test and replace the element.

    Stop here: call a competent engineer.

  9. Outcome: Grill / top element

    Likely cause: The top element has failed.

    What to do:

    1. Isolate. Engineer to replace the element.

    Stop here: call a competent engineer.

  10. Outcome: Thermostat, cut-out or board

    Likely cause: No heating at all suggests the thermal cut-out, thermostat, selector or relay board.

    What to do:

    1. Isolate. Do not bypass the thermal cut-out.
    2. Book an engineer.

    Stop here: call a competent engineer.

Tumble dryer not heating 5 questions, 5 outcomes

Tumbling, but clothes stay cold and damp.

  1. What type of dryer is it?

  2. Is the vent hose clear, not crushed, and less than the maximum length in the manual?

  3. Have you cleaned the fluff filter(s) and the condenser/heat exchanger, and emptied the water tank?

  4. Does the drum turn and it just blows cold?

  5. Outcome: Blocked or restricted vent

    Likely cause: Restricted exhaust trips the overheat cut-out - and is a fire risk.

    What to do:

    1. Clean the fluff filter and clear/straighten the vent hose.
    2. Replace a crushed hose.

  6. Outcome: Filters / condenser blocked

    Likely cause: Blocked airflow reduces heat or stops heating via protection.

    What to do:

    1. Clean all filters and rinse the condenser unit, let it dry, empty the tank.

  7. Is it a heat pump dryer and the room is below about 10 C?

  8. Outcome: Drum not turning

    Likely cause: Broken belt, door switch or motor fault.

    What to do:

    1. Unplug. Book an engineer.

    Stop here: call a competent engineer.

  9. Outcome: Room too cold for the heat pump

    Likely cause: Heat-pump dryers lose performance in cold garages.

    What to do:

    1. Use it in a room above ~10 C if possible.

  10. Outcome: Heater, thermal fuse or thermostat fault

    Likely cause: A blown thermal fuse often follows a blockage.

    What to do:

    1. Unplug. Clear any blockage first.
    2. Engineer to test the element, fuse and thermostats; heat-pump dryers contain refrigerant, so sealed-system repair needs a qualified refrigeration engineer.

    Stop here: call a competent engineer.

Related: look up a fault code with the HVAC error code finder or the appliance error code finder, find the official manual with the appliance manuals finder, and prevent repeat faults with the preventative maintenance checklist. Practise fault-finding with Tradefox training courses.

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