Contents: Air conditioning system ⇊ Heating system ⇊
Air conditioning system
Warning! The air conditioning system is under constant high pressure. Never disconnect refrigeration lines or remove any system components without first discharging the system. Discharging the air conditioning system must be done by an experienced technician in a car service workshop. Always wear safety glasses when disconnecting refrigeration lines!
Caution! When replacing air conditioning system components, a certain amount of replacement refrigeration oil will be required to fill the volume of the new unit. Use only oil suitable for use in R-134a systems (read the container label carefully).
Service
The following checks should be performed on a regular basis to maintain the air conditioning system in good working order:
- a) Check the condition of the compressor drive belt. If defects or signs of wear are detected, replace it (see Chapter Routine maintenance);
- b) Check the tension of the drive belt and adjust it if necessary (see Chapter Routine maintenance);
- c) Check the refrigeration hoses for cracks, swelling, signs of hardening and aging of the rubber. Replace if necessary;
- d) Check the condenser plates for insect remains, old leaves and other debris stuck between them. If necessary, clean the gaps with a thin brush or blow them out with compressed air;
- e) Check the system charge level;
- f) If water leaks are found on the floor mats under the instrument panel, remove the condensate drain pipe from the evaporator housing (located in the lower front corner) and use a piece of wire to check the patency of both holes (see accompanying illustration).
The air conditioning system should be turned on for at least 10 minutes at least once a month (even in winter). Long-term inactivity of the K/V leads to hardening and failure of the sealing rings and cuffs of the connecting tract.
Note: When the deicing function is turned on, the A/C compressor is activated.
In case of malfunctions in the operation of the compressor, first of all check the proper functioning of the compressor clutch (see Checking the electrical circuit of the K/V compressor clutch).
Due to the complexity of the system design and the need to use special equipment, its maintenance, in-depth diagnostics and repair are beyond the skill level of the average amateur mechanic and should be performed in a car service workshop. The car owner is only competent to perform the simplest checks and replacements listed below in this Manual.
The most common cause of malfunction of the air conditioner is a decrease in the charge level of the refrigerant oil. The following simple tests will allow you to quickly identify signs of a decrease in the refrigerant level.
Examination
1. Warm up the engine to normal operating temperature.
2. Turn on the air conditioner to maximum cooling capacity. Select the maximum fan speed. Open the doors to eliminate closed air circulation in the cabin.
3. Insert the thermometer into the air outlet duct through the center deflector on the instrument panel (see accompanying illustration). When the air conditioner is on, the temperature of the air coming out of the deflector should be within 2°C÷8°C. In very hot weather (40°C), an increase in the outlet temperature to 15°C is permissible, but not more.
4. If the requirements listed in the previous paragraph are not met, then the system needs charging. For a more detailed diagnosis of the system's condition, the car should be taken to a specialized workshop.
Adding refrigerant
Caution! Only R-134a refrigerant oil should be used to charge the air conditioning system of the vehicles covered in this Manual.
1. Prepare a standard R-134a charging kit (ask in car accessories stores). The kit includes a can of refrigeration oil, a valve nozzle and a section of hose that is connected between the valve and the low-pressure part of the refrigeration line (see accompanying illustration). Since one can of oil may not be enough to fully charge the system, it makes sense to buy a couple just in case. Make sure that at least one of the cans has oil tinted red, which will allow you to quickly identify refrigerant leaks if they occur.
Attention! Never fill the system with more than two cans of refrigerant!
2. Connect the charging kit to the system in accordance with the manufacturer's instructions. The design of the nipple connections allows the kit to be connected only to the low-pressure part of the system.
Attention! Do not attempt to connect the kit to the high-pressure part of the tract under any circumstances!
3. Close the valve on the adapter and screw the latter onto the head of the can, having first checked that the sealing ring/rubber gasket is present.
Attention! Be sure to wear protective glasses!
4. Remove the dust cap from the low-pressure part of the refrigeration line and connect the charging kit hose equipped with a quick-connect connector to it (see accompanying illustration).
5. Warm up the engine and turn on the A/C. Make sure that the charging kit hose does not come into contact with the fan blades of the engine cooling/air conditioning systems.
Note: The system must be charged with the compressor running. If the compressor clutch disengages, the system must be switched to maximum cooling capacity and all cabin doors must be opened.
Note: To prevent the compressor from shutting off during charging, disconnect the connector from the low-pressure switch (some models use a combination low/high pressure switch) and bridge it with a paper clip or a piece of wire.
6. By rotating the valve nozzle, pierce the head of the cylinder, thereby opening the supply of refrigerant (you should hear the characteristic sound of escaping gas). During the entire charging process, hold the can strictly vertically, shaking it from time to time. Between two series of charging, make a pause necessary for the system to stabilize.
7. If you have an accurate thermometer at hand, insert it through the deflector into the central air duct of the air conditioner and use it to monitor the temperature of the air supplied to the passenger compartment (see paragraph 3 "Checks").
8. When the can is empty, close the valve and disconnect the hose from the low-pressure fitting of the system. Immediately put the dust cap on the fitting.
9. Disconnect the valve nozzle from the cylinder, if necessary, move it to the second cylinder and continue filling. After completing the procedure, place the unfinished cylinder vertically on the rack and use it to recharge the system as needed.
Heating system
1. Wetting of the carpet on the floor under the heater heat exchanger, or steam escaping through the air duct deflectors indicate leaks in the heater heat exchanger. Remove the heat exchanger (see Replacing the heater heat exchanger) and replace it with a new one (the heater heat exchanger is not subject to repair).
2. If the heater does not heat the air supplied to the passenger compartment, the reason for such failure may be one of the following:
- a) The thermostat is stuck in the open position, allowing the engine coolant supplied to the heater heat exchanger to heat up to the required temperature;
- b) There is a blockage in the cooling tract, which blocks the supply of coolant to the heater heat exchanger. Feel the hoses connected to the pipes on the rear bulkhead of the engine compartment - both of them should be hot, otherwise the tract is blocked (the hoses, heat exchanger, or heater control valve are blocked). Disconnect the hoses and reverse flow the heat exchanger. After disconnecting, flush both hoses as well.
- c) If it is not possible to restore the heat exchanger's patency by flushing, the unit should be replaced.
(Original published on this resource Hondabook.ru)