1, lack of coolant
Cause: The engine water circulation system parts are damaged, the interface leaks or the cylinder gasket is damaged, resulting in insufficient coolant, so that only a small amount of coolant circulates in the warm air pipeline or there is no circulation at all, resulting in the warm air is not hot.
Solution: Replenish the coolant to ensure the normal water circulation system of the engine. If there are other problems, please solve them first, and then add coolant to the normal level.
2. Thermostat
Cause: The thermostat was removed or damaged in the normally open position because the water temperature was too high during the previous maintenance, which kept the water circulation of the engine in a large cycle. In addition, due to the low external temperature and good heat dissipation, it is difficult to raise the water temperature of the engine, so the warm air is not hot.
Solution: Add or replace a new thermostat.
3. Warm air water tank and heat exchanger
Reason: Some models of heaters have exhaust ports near the water tank. If the exhaust is not complete, the heaters will not be hot.
Solution: If there is an exhaust port, exhaust the air first. If you can't touch the two heating pipes by hand and the temperature difference is great, you can directly connect the heating tank or heat exchanger with a water gun or an air gun.
4. Warm air control mechanism
Cause: Air conditioning panel, cold and hot servo motor, heater water valve and other parts are damaged or the heater system circuit is faulty, resulting in the heater not being used normally.
Solution: find out the reasons and deal with the specific problems.
Extended data:
Causes of air conditioner damage:
1, heater water tank blocked
The blockage of the heater water tank is also a possible reason why the heater is not hot. The structure of the warm air water tank is actually a miniature version of the radiator of the engine water tank, and there are many small cooling pipes in it, which are as easy to block as the radiator of the water tank. After the inside of the warm air water tank is blocked, the coolant flows slowly, the flow rate becomes smaller, and the heat is insufficient, so the air conditioner warm air is naturally not hot. Clean the inside of the warm air water tank and the radiator of the water tank.
2, warm water valve failure
The warm water valve is actually an electric control valve, which is installed between the intake pipe of the warm air box and the small circulation pipeline of the engine. The opening of the valve is controlled by the air-conditioning computer, so as to control the refrigerant flow into the warm air box and achieve the purpose of controlling the warm air temperature of the air conditioner more accurately.
After the hot water valve fails, the opening of the electronic control valve is no longer controlled by the computer, and it is in the state of normally open, normally closed or fixed position. At this time, there is no coolant flowing through the warm water tank or the flow rate is uncontrolled, so the warm air temperature of the air conditioner is naturally uncontrolled.
The thermostat is always on.
If the thermostat is always on, it will also cause the warm air to be not hot. After the thermostat is normally open, the coolant begins to circulate from the idle speed of the engine. If the water temperature is low for a long time in winter in the north, the air conditioning warm air is naturally not hot. It is obvious from the thermometer that the pointer is obviously lower than the normal scale. In addition, low water temperature for a long time will lead to high fuel consumption, increased wear and tear, and the engine will not work at the optimal temperature; When the water temperature is low for a long time, it needs to be maintained and checked immediately.
4. Insufficient antifreeze
The lack of antifreeze in the cooling system is the most common reason why the warm air is not hot. When designing the engine cooling system, engineers will give priority to engine heat dissipation, and then the warm air can work normally.
When the coolant is insufficient, the coolant will circulate in the engine first. At this time, there is no "water" in the warm air circulation pipeline, and most of the warm air tank is gas. At this time, the air conditioning warm air is naturally not hot. After adding antifreeze, the warm air tank is filled with boiling coolant, and the warm air will naturally heat up.
Phoenix. Is the com- air conditioner heater broken in winter? It turns out that they are the culprit.