H Block Expansion Valve Operation
There are two common types of expansion valves.
H block expansion valve operation. How to test an h block style expansion valve. Preparing for the expansion valve test. This type of valve is usually located at the firewall between the evaporator inlet and outlet tubes and the liquid and suction lines.
It s either near the firewall or under the dash. An expansion valve also called a tvx valve regulates the flow of refrigerant inside of a cooling system. Connect your gauges to the car ac high and low service ports.
The valve holds back the high pressure liquid refrigerant from the condenser and controls how much refrigerant can pass into the evaporator. This valve is found on early 2000 s europe. In this video i simulate and visually show the throttling operation of an automotive expansion valve made by tgk.
You ll need a manifold gauge set and a full can of dust off spray. These types of valves although efficient have some disadvantages over orifice tube systems. The valve decreases the pressure to allow the refrigerant to boil at lower temperatures.
The first system is called a thermal expansion valve txv system. Like orifice tubes these valves can become. This system also has a receiver drier on the liquid line.
The txv is a variable control valve located at the entrance of the evaporator. First determine if the h block expansion valve is accessible. Thermal expansion valve txv system.
Water boiling at different temperatures due to changing pressure.
