- *LCU Power Exhaust Wiring Made Easy.
1. For the low voltage wiring for the power exhaust relay, even if the wire numbers do not match the instructions in your kit the red wire will splice into the red wire on the 4-wire MODBUS connector on the RTEM. The same will apply to the blue common wire for the coil on the relay, it will splice into the blue wire on the 4-wire MODBUS connector on the RTEM.
2. For the line voltage wiring for the power exhaust motor. If the unit does not have a VFD for the indoor blower motor, then simply land the 2-line voltage wires from the power exhaust motor to the line side of the compressor contactor. If the unit is equipped with a VFD, place the line voltage wires from the motor to the incoming line voltage side of the FTB at the VFD.
3. If the unit does not have an RTOM installed the power exhaust set is defaulted to run when the outside air damper is 25% open or greater. If the unit has an RTOM installed the power exhaust set point can be field adjusted by using the EXH trim pot on the RTOM, This can be field adjusted to a set point between 0%-100% to enable the power exhaust to run when the outside air damper reaches that position.
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.