If you need to replace the AC evaporator, it is best to have this done at a dealership or repair shop. Doing this replacement requires draining the refrigerant, which is unsafe to do yourself, and can be illegal.
about $2000.
behind glovebox in side of evaporator it has a 2 pin connector.
Honda Element was created in 2003.
You can find a Honda repair manual at most local libraries. You can also find the repair manual at most Honda dealerships.
Thermostatic expansion valve consists of a thermal sensing element that regulates the flow of liquid refrigerant into an evaporator based on the temperature of the refrigerant returning from the evaporator.
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Inside the evaporator case which is behind the glovebox
There are many features of a 2003 Honda Element. The biggest features of the 2003 Honda Element would be the leather seats, the radio, and the air conditioning.
You can flush the evaporator out, or replace it. Both will require specialty knowledge in repairing air conditioning systems. Take your can in to a professional to have it fixed.