The ICM870 series soft starts ARE compatible with 2-stage HVAC units. If your 2-stage unit has two compressors, you will need two ICM870 units.
The ICM870 Soft Start is intended for residential, commercial, RV & marine applications. The ICM870 integrates compressor or motor in-rush current over startup time, thus reducing peak current demand on a power supply source by up to 70%.
Effectively reducing power draw to the A/C, the ICM870 utilizes a built-in self learning algorithm to deliver the optimal in-rush current per application. The ICM870 will monitor system health including voltage, current, compressor startup and integrity. Upon a fault condition, it will halt operation and initiate a 3 minute anti-short cycle routine while providing diagnostic fault information by means of an LED indicator.
ICM870-9A: For use with a Compressor Load Amp Rating (RLA) of up to Maximum of 9A
ICM870-16A: For use with a Compressor Load Amp Rating (RLA) of 9.1-16A Maximum
ICM870-32A: For use with a Compressor Load Amp Rating (RLA) of 16.1-32A Maximum
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