Unfortunately, there are numerous reasons as to why your car's heater could stop working. Symptoms often relate to: 

• Heater cores and coils

• Radiators and heater hoses

• Heater blower motors

• Thermostats and temperature sensors

• Electronic heating controls and blend doors

• Faulty demisters and fogging issues

Etc... It can be hard to diagnosed what has caused your issue over the phone, so it's best if you bring the vehicle in to see us so that we can get a much better understanding as to the issue you're experiencing and what is causing it. Once we've concluded the fault, we can run you through a quote for repairs and come up with a plan with you, to get your car back to being warm, safe and dry.

If you're finding that your car is not producing adequate airflow at the vents when on the heater function, your issues could be caused by a blocked cabin air filter, a faulty blower motor, and rarely, an externally blocked heater core. 

If you're experiencing low poor airflow from the vents of your car, we recommend that you bring your vehicle in to see us so that we can take a look at it and pinpoint exactly what has caused this issue. Once we've come to a conclusion we can take you through a quote and advise you on the appropriate repairs for your vehicle to ensure airflow is restored. 

If your windows are not demisting properly, it is likely because your vehicle's heating, air-conditioning or ventilation system is not working as it should. Some don't realise that the A/C system helps to demist your windows, even during the winter time. The A/C removers moisture from the air before it is blown onto the glass, which aids in clearing condensation much faster. 

If your demister is blowing air but the windows stay foggy, the system may not be drying or directing the air properly. If the airflow is weak,  there may be a blockage, filter issue or fan fault.

We'll check your A/C, heating, cabin filter and airflow to find out why your windows are not clearing as they should. Having established the cause, we can recommend the best repair or treatment to get your demister working as it should. 

Some common issues of poor demisting include:
Low refrigerant or an A/C system fault

• A blocked or dirty cabin filter

• Weak airflow from the vents

• A faulty blower fan

• Heater or temperature control issues

• Recirculation mode staying on

• Blocked vents or air intake areas

• Excess moisture inside the vehicle

• Water leaks into the cabin

• Faulty heater controls, blend doors, or actuators

Yes, a leaking heater core can cause wet carpet inside the vehicle, usually in the front footwell area. The heater core sits inside the vehicle's heater box, so if it, or the heater core inlet/outlet pipes, seals or hose connections are leaking, then coolant can escape into the cabin. 

However, wet carpets aren't always caused by the heating system. Air-conditioning faults can also cause moisture to accumulate inside the vehicle. Common A/C related issues include a blocked evaporator drains which prevents condensation from draining outside the vehicle, or excess condensation caused by low refrigerant or poor evaporator performance. 

It's best to bring the vehicle in to see us at one of our workshops so that we can get a better understanding as to what exactly has caused the wet carpets, as it is difficult to diagnose this issue over the phone or without having seen the vehicle. Once we've determined the source of the moisture we can quote you for the necessary repairs accordingly. 

Yes. Low coolant can stop your vehicle's heater from working properly, as the heater replies on hot coolant flowing through the heater core to warm the air entering the cabin.

If the coolant level is low, there may not be enough coolant reaching the heater core, which can cause poor or intermittent, heat at the vents. Low coolant can also allow air into the cooling system, creating air locks that restrict flow though the heater core. 

Low coolant issues should be checked thoroughly, as it may indicate a leak from the radiator, hoses, water pump, heater pipes, etc. Additionally, this can lead to the engine overheating if left unresolved. 

To confirm any coolant issues, bring your vehicle in to see us so that the leak can properly be diagnosed, and quoted for your approval. 

Yes, if the thermostat is faulty, this can cause poor cabin heating because it controls how the anti-freeze through the engine and the cooling system. 

Functioning like a temperature dependant valve - If the thermostat is stuck open, the engine may take too long to reach its normal operating temperature.  This is because the heater relies on the hot coolant flowing through the heater core. This can mean the heater only blows lukewarm air, especially when driving on the open road.

To confirm whether the thermostat in your car is not working as intended, come in to one of our workshops so that we can properly diagnose and confirm this fault before quoting you for the necessary repairs.

Yes, mixing different coolants/anti-freeze can affect the heating system.  Mixing the wrong coolants can cause chemical reactions and incompatibility that often inhibit the efficiency of your vehicle's heating system. Additionally, differing corrosion inhibitors found in anti-freeze is designed for specific engine and cooling system materials. If used incorrectly or mixing different types can cancel out those protections or create deposits. Including:

• Sludge , gel or abrasive filament forming in the cooling system

• Blocked heater core or radiator

• Reduced corrosion protection

• Damage to aluminium components

• Seal and gasket deterioration

• Exacerbated water pump wear

• Overheating and/or poor performance

Hence it is important that anyone going near your vehicle's heating system has a good understanding of what antifreeze can already be found in your vehicle, and that which is recommended to ensure no mishaps are caused. 

Yes. Poor cabin heating can be a sign of a cooling system problem, as your vehicle's heater relies on hot coolant flowing through the heatercore to warm the air entering the cabin. 

If there is low coolant, an air lock, a blocked heater core, faulty thermostat, leaking heater pipe or poor coolant circulation, the heater may blow cool or lukewarm air, work only sometimes, or struggle to demist the windscreen, among other things. 

Poor heating should not be ignored, especially if it is accompanied by low coolant levels, engine overheating, a sweet smell inside the vehicle, wet carpets, or warning lights. These symptoms indicate a leak or cooling system fault that should be checked out as soon as possible to ensure the well being of yourself and your vehicle. 

Yes! Heater and ventilation problems can cause your car to have an unpleasant smell. 

If you're experiencing a sweet, syrupy smell - this could indicate leaking anti-freeze, potentially onto the carpets in your front footwells. 

A damp musty smell could be caused by moisture trapped in the heater or air-conditioning system, a blocked evaporator drain, mould or baceria growing in the system or a dirty and blocked cabin air filter. 

Burning smells can point to electrical faults such as a failing blower motor, dodgy wiring, or debris in the vents. 

As different smells point to different faults, we recommend that you bring the vehicle in to see us so that a qualified technician can examine the system, to diagnose the issue. Once the fault has been concluded, we'll quote the necessary repairs and come up with a plan to get your vehicle's heating system back to top quality. 

Yes! There are some makes and models of vehicles that are more prone to having heating issues. However, less so than vehicles that have air-conditioning issues. One common vehicle that often faces heating issues is a Ford Focus. 

This depends on what has caused your vehicle's heating system to stop working. 

If you're finding that in conjunction with your heater issues, the temperature gauge is rising, your engine is overheating, you can smell a sweet smell, or that your front footwell carpets are moist - It's likely that your heating issue is caused by a coolant leak. It is not advisable to drive the vehicle whilst the engine is compromised. 

If the heater is not producing warm air, yet the engine temperature appears normal, you're likely okay to drive the vehicle in to see us so that we can examine the system, and accurately determine what has caused your vehicle's heating to stop working. We can prepare a plan and quote for repairs from there to address the issue. 

If you're finding that your heater is only working on a high fan speed, it is likely caused by a faulty blower motor, or fan speed resistor. These parts control the lower fan speeds, so often times when they fail, the fan may only operate on full speed. 

This could also potentially be caused by damaged wiring, a faulty fan switch, poor connections, or issues with the heater/ac control panel. 

If you're having trouble with your fan not blowing, or your heater only functioning on high fan speeds, bring your vehicle in to see us so that we can pinpoint what exactly has caused your car's fan to stop working as intended. Once diagnosed, we can prepare a quote and walk you through the repairs necessary to get it back to working order. 

Yes. CoolCar can repair, restore, and adapt heating systems in classic cars, custom vehicles, hot rods, and older vehicles where original parts may be difficult to source.

We can assess heater cores, heater boxes, blower motors, heater taps, hoses, controls, vents, demisters, airflow problems, coolant leaks, and electrical faults. Where replacement parts are no longer available, we can often repair existing components, make or adapt heater hoses, or recommend a practical solution to get the heating and demisting system working properly again.

Whether you want to keep the vehicle as original as possible or improve comfort and usability, we can help find the right repair approach for your classic vehicle.

Yes! Stop leak products can potentially damage or block a heater core. A heater core has very small holes, and stop leak is designed to seal holes similar to this. Whilst it may temporarily slow down a coolant leak. It can also collect inside the radiator, thermostat, heater tap, and hoses. 

This can restrict coolant flow and cause poor cabin heating, intermittent heat, or more extensive cooling system problems. 

Stop-leak may have a place as a short-term emergency measure. But it should certainly not be treated as a proper repair. The best approach would be to identify the source of the leak and have it repaired correctly, then re-fill the system with the correct coolant for the vehicle and bleed off the air remaining in the cooling system. 

If one side of the vehicle is warm and the other side is cold, this is often caused by a faulty in the air distribution system or temperature control system. 

Many modern vehicle's have dual-zone climate control. if the system is not working correctly, one side may receive heated air  whilst the other side stays cool. 

Common causes include a faulty blend door actuator, stuck or broken temperature flap, electrical faults, blocked heater core, or restricted coolant flow. 

In some vehicles, a partially blocked heater core can also cause the uneven eating across the cabin. The correct repair depends on whether the issue is with coolant flow, airflow direction, electronic controls or the heater box itself.

We reccomend that you bring the vehicle in to see us so that we can determine what exactly has caused the vehicle's heating system to stop working as intended. This way we can quote the necessary repairs accordingly to get your car back to being dry, safe and cosy.