Description
The Lennox 38M78 is a low ambient pressure switch, which is safety equipment installed in Lennox HVAC equipment such as heat pumps. It has theessential task of protecting the system during cold weather operation. Thus, the switch protects against possible damage due to low temperature, if it maintains control of refrigerant pressure. If the pressure goes low, normally at about 450 psi for 38M78, the switch turns off the system automatically. This helps to avoid the compressor from trying to compress low pressure that will cause overheating and failure of the compressor components. the switch enables the compressor to turn on.
