One problem with many of these little remote units (not the IVAC) is how they are rated. 15 Amps is not the same for all equipment- what I am saying is look closely at the ratings- 15 Amps resistive load (heater, lighting, hot plate, etc.) is not the same as 15 Amps inductive load (motor, transformer, etc.). If you look at most US manufactured switches, etc, you will see they have two ratings, one for inductive loads and one for resistive load. A switch rated for 15A resistive load many only be rated at 10A inductive load. A switch used with inductive loads must be able to handle blowback which is caused by a surge of voltage created by the collapsing magnetic field in an inductor. When switching inductive loads, the arcing and sparking which normally occurs and damages the switch contacts over time happens when the contacts make AND break. I suspect many of the cheap remotes are not rated or not properly rated for inductive loads.