When evaluating how a humidistat switch might work in switching something like a Sears basement-type dehumidifier, you should look beyond the amperage spec for the switch. The Dampp-Chaser elements that are normally used are all resistive heating elements. Therefore the current and voltage are always in phase, and switching a load is quite gentle on the switch. However, something like the Sears unit has a compressor motor. Motors have coils and so are inductive. Whenever you try to disconnect an inductive load, the "inertia" of the current tries very hard to keep the current flowing, sometimes producing a visible arc if you pull the plug on a running motor. These arcs are created by generated voltages much higher than the applied 120 volts, and these arcs are destructive to switches, especially if they happen continually, as would be the case in a humidistat-controlled humidity control system. So I would definitely use a relay to control such a thing rather than try to run the Sears dehumidifier directly off of the Dampp-Chaser humidistat. Robert Scott Real-Time Specialties
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