Our service team often hear these common questions about HVAC or climate control in farm machinery:

• My tractor's blower motor has just stopped working. How can I find out if it is the circuit breaker, the fan switch or the blower motor itself?
• My Massey Ferguson 365 tractor has climate control but the blower suddenly stopped working. All the fuses have been checked but there doesn't appear to be one for the blower motor. Do I need to replace the blower motor assembly?
• Electrical wiring in my JD 4630 seems to be a mystery. The radio works but as soon as the air conditioning is turned on the radio goes off and the fan doesn't turn on. Where can I find parts diagrams?

Whatever the answer you will need spare parts to fix it. At malpasDirect we have a wide range of air-conditioning related parts, all cross referenced by OEM part number and machine model.

Please Note: Some of the links below will take you to malpasAirflow.co.uk, our sister website specialising in vehicle heater fans. air-conditioning blower motor assemblies and accessories.

Product Range (Technical Parts)

You can view our full range of Air Conditioning Components or filter your search by selecting from our most popular categories below:

Product Range (Universal Parts)

We can also supply a range of Universal Air Conditioning parts which can be filtered by these categories below:

Key Components Of A Standard Air Conditioning System

Thermal Expansion Valve - Often considered to be the intelligent part of a tractor’s air conditioning system, the expansion valve regulates the amount of refrigerant delivered to the evaporator by lowering the pressure of the refrigerant liquid, allowing it to expand and turning it into a vapour by gauging the temperature and pressure level from the condenser. Expansion valves are one of the key components to any air-con system as too much of refrigerant entering the evaporator can cause the evaporator to freeze, block up, and potentially burn out the HVAC motor. This can also lead to the refrigerant remaining in liquid form and potentially entering and damaging the compressor.

Condenser - If you are lucky enough to have a tractor cab fitted with an air conditioning system then you’ll know that to keep this maintained during the hotter months is incredibly important for the welfare of the machine operator. Part of the air-con system is the condenser whose role is to convert the refrigerant gas to a liquid whilst dissipating its temperature. Situated at the front of the machine it looks similar to a car radiator in appearance and is normally cooled using an electric fan. To keep your air conditioning fully operational and to avoid the sweltering heat for you and your operators make sure that your air-con is kept in good condition and replace any broken Air Conditioning Condensers. Key tasks to check on a condenser are split tubes leading to/from the unit and look for any signs of damage to the condenser fins that could stop the refrigerant from cooling and cause bigger issues within the air-con system.

Compressor - A standard air conditioning system comprises of a few key components, one of which is the compressor. A tractor's compressor pressurises the system's refrigerant gas whilst simultaneously raising its temperature before condensing it into a liquid. The compressor is powered by a belt driven by the tractors engine. It is the main cooling component for any tractor’s air conditioning system and can be a complex device that can suffer a number of faults, such as a lack of oil, leaky seals, or faulty wiring connections. Choosing the right replacement compressor, associated parts or appropriate oil for your model of tractor is essential.

Blower Motor - The main purpose of a HVAC blower motor is to use the cool air produced by the evaporator and blow it through the air-conditioning vents into the tractor cab. This airflow is used to control the temperature inside the cabin by recycling the warm air back onto the evaporator fins before returning it to the cab as cool air. The quality of a blower motor is usually governed by the amount of airflow that it can provide, how long the motor is designed to be used for and the noise level. There are many different variants of a blower motor, for instance, they can be supplied in both 12v and 24v versions to suit different applications. An everyday example of this would be that cars and tractors usually have 12v DC power supplies whereas buses, coaches and construction equipment would have 24v supplies. Also a blower motor assembly can either be single or double rotor equipped. In tractors, especially John Deere models where the air conditioning components are often integrated into the roof of the cab, two single blowers are used in place of a larger double blower as it gives more flexibility in terms of mounting options making a more compact assembly.

Evaporator - The role of an evaporator is similar to that of the condenser except that the physical location being the key difference. Situated close to the tractor cabin/compartment, the evaporator takes the cooled liquid and vaporises it using the hot air taken from inside the cab that is sucked in by the tractor’s blower motor, which then blows air over the exterior fins of the evaporator and circulates the cooled air back in to the cab area.

Switches – Control panels and electrical switches inside a cab are used to regulate an air-conditioning system either through a thermostatic switch or simply controlling the blower motor speed. You will find many of the switches listed being suitable for blower motors and fans you can find on this website. Switches can be rotary or toggles. In some cases, there are multiple positions such as those used to control the different fan speeds.

Drier or Accumulator - A vehicle equipped with cabin air-conditioning will be fitted with either a drier (also known as a receiver-drier), or an accumulator. These self-contained sealed cylinders look similar and they perform the same task which is to trap unwanted moisture or foreign debris in the air conditioning to avoid an underperforming system. They are also responsible for limiting the amount of refrigerant that enters the system’s evaporator. A drier is smaller and more compact compared to an accumulator and is plumbed in to the structure between the condenser and expansion valve in the high pressure part of the air-con system. Where as an accumulator is designed to connect to the low pressure part of the system on the evaporator’s outlet.