No heating or hot water
The cause may be a control setting, failed sensor, circulation fault, zone valve, pump, low system pressure or refrigeration fault. We test demand, flow and heat transfer rather than assuming the outdoor unit has failed.
Free Survey · Fixed-Price Quote in 48 Hours
Heat Pump Repair in London
Heat pump repair in London from £120+VAT. Fast diagnostics for all heat pump faults, emergency callouts available. Call now.
Fast fault diagnostics
Emergency callouts available
Major brands serviced
Repairs from £120+VAT
Google5/5 (547 reviews)
F-Gas Registered
7-Year Warranty
5,000+ Systems Installed
Heat Pump Repair London: Direct Answer
Heat pump repair in London starts with fast, systematic fault diagnosis for air source systems that have stopped heating, iced up, become noisy or lost efficiency. Emergency callouts are available, with repairs priced from £120+VAT.
A heat pump combines refrigeration, water circulation, electrical controls and weather-responsive software. A symptom in one part of the system can be caused elsewhere, so replacing parts without testing often wastes time and money. Our engineers read the fault history, test the operating conditions and identify the underlying cause before recommending work.
Common Heat Pump Faults We Repair
Ice buildup
Some frost is normal before a defrost cycle. Heavy or persistent ice can indicate blocked airflow, failed fans, drainage problems, sensor errors, low refrigerant or a defective defrost sequence.
Strange noises
Grinding, rattling, humming and water noise can point to fan bearings, loose panels, circulation pumps, trapped air, poor flow or compressor stress. Early diagnosis can prevent secondary damage.
Low efficiency
Rising electricity use or rooms taking longer to warm may result from dirty coils, poor water flow, an unsuitable heating curve, low refrigerant charge, cycling or an incorrectly configured backup heater.
Error codes and lockouts
We record the code before resetting it, review operating data and test the circuit named by the manufacturer. Repeatedly clearing a code without finding the cause can turn an intermittent problem into a major failure.
Leaks and pressure loss
Water around the cylinder, buffer vessel, pump or valves requires prompt attention. We identify whether the leak is hydraulic, condensate or refrigerant related and isolate the system safely where necessary.
Heat Pump Brands Serviced
We service and repair Mitsubishi Ecodan, Daikin Altherma, Samsung EHS, LG Therma V, Grant Aerona and NIBE heat pumps. We also investigate faults on many other monobloc and split air source systems, subject to technical information and parts support. Please provide the model, serial number and displayed error code when booking so we can prepare for the visit.
- Mitsubishi
- Daikin
- Samsung
- LG
- Grant
- NIBE
Our Heat Pump Diagnostic Process
- 1
System history and visual inspection
We discuss when the fault began, note recent changes, photograph the installation and inspect the outdoor unit, cylinder, pumps, valves, filters, emitters and controls for visible defects.
- 2
Controls and electrical testing
We read stored error codes, confirm heating demand, inspect electrical connections and test relevant sensors, actuators, protective devices and power supplies using manufacturer information.
- 3
Water flow and temperature checks
Flow rate, system pressure, pump operation and temperature difference help reveal blockages, airlocks, closed valves, undersized pipework, poor balancing or failing circulation components.
- 4
Refrigeration and performance assessment
Where symptoms indicate a refrigeration issue, an appropriately qualified engineer checks coil condition, fan operation, pressures and temperatures. Refrigerant is never treated as a consumable top-up.
- 5
Clear repair recommendation
We explain the cause, safety implications, available parts and repair price. After work, the system is run under demand and the relevant temperatures, flow and controls are checked again.
Emergency Air Source Heat Pump Repair
Emergency appointments are available across London when a breakdown leaves a property without heating or hot water, when water is leaking, or when continued operation risks further damage. Availability depends on engineer location, safe access and parts. We may provide a temporary safe setting where a permanent repair requires a manufacturer-specific component.
If there is burning, smoke, exposed wiring or a serious water leak, isolate the relevant supply only if it is safe to do so and contact the appropriate emergency service. Do not remove covers, break ice from a coil or repeatedly reset a unit that immediately returns to lockout.
Repair or Replace Your Heat Pump?
Repair is usually the best route when the fault is isolated, the system was correctly sized and installed, parts remain available and the unit has useful service life remaining. Pumps, sensors, fans, valves, controls and minor electrical components can often be replaced economically.
Replacement deserves consideration after a major compressor or heat-exchanger failure, repeated refrigerant leaks, widespread corrosion, obsolete controls or several connected failures. We compare likely repair cost, age, parts support and current seasonal performance. The recommendation includes the wider system, because poor emitters, pipework or controls can make a new outdoor unit perform badly too.
Heat Pump Repair Pricing
| Service | Price | What it covers |
|---|---|---|
| Heat pump fault diagnosis | From £120+VAT | Initial inspection, fault-code review and system testing. |
| Emergency callout | Quoted on booking | Priority attendance subject to time, location and availability. |
| Parts and additional labour | Quoted after diagnosis | A clear repair scope before further work proceeds. |
Prices exclude VAT. Access equipment, specialist manufacturer support and refrigerant work are quoted where required.
Heat Pump Repair FAQs
How much does heat pump repair cost in London?+
Heat pump fault diagnosis and repair starts from £120+VAT. The final price depends on the fault, replacement parts, access and testing time. We explain the diagnosis and provide a clear price before carrying out additional repair work.
Do you offer emergency heat pump repair near me?+
Yes. Emergency heat pump repair callouts are available across London, subject to engineer and parts availability. We prioritise homes without heating or hot water, serious leaks, electrical concerns and faults that could damage the compressor.
Can you repair every make of air source heat pump?+
We diagnose and repair air source heat pumps from Mitsubishi, Daikin, Samsung, LG, Grant and NIBE, plus many other established manufacturers. Parts availability and manufacturer support can vary for older or discontinued models.
Why is my heat pump covered in ice?+
A light frost that clears during a defrost cycle can be normal. Persistent ice may indicate restricted airflow, a sensor problem, failed fan, drainage issue, low refrigerant charge or a defrost-control fault. Switch the system off if ice threatens the fan and arrange diagnosis.
Is it better to repair or replace an old heat pump?+
Repair is normally sensible when the unit is serviceable, efficient and supported by available parts. Replacement may offer better value when the compressor has failed, refrigerant or parts are obsolete, several major components are worn, or repair costs approach the value of a modern system.
Related Heat Pump Services
Ready to Book Your Heat Pump Repair?
Get a fixed-price quote today. Our F-Gas registered air conditioning and heat pump engineers cover London and the Home Counties seven days a week, with rapid response for breakdowns.
Installations from £1,795 + VAT • Free survey • F-Gas registered engineers