Quote Originally Posted by spyderrobotics View Post
Semiconductor switching of course is best solution but has its own problems with heat output and is not something that can be added to correct the problem with the thermostat they already have. ...
Your link to line filters is for components and not a plug in solution. I was thinking more towards line conditioners that would be a plug in solution and may have built in line filters and such.
If semiconductor heat is so problematic, then dimmer switches would even be hotter. Semiconductor switching is problematic when a switch is not properly designed. For example, if a switch uses a transistor, then heat can be problematic. Other semiconductor solutions (as found in dimmer switches) exist.

For example, that thermostat can drive a box containing a better switch (ie relay); that does not arc. A thermostat that conducts well less than 1 amp (to power that box) should not arc.

Retail price of filters is provided. Manufacturers box same filters (purchased at wholesale prices) and add a plug and receptacle. Then it sells at profit for a similar price. Demonstrated are filters (and costs) found inside filtered appliances and inside plug-in filters. Or build one. So again, a question. What number defines expensive?

Other numbers. What is an electrical specification for that thermostat switch? What numbers are for a heater. Better answers exist when numbers are provided. No numbers often results in answers that are only speculation or hearsay. And may even explain a previously discussed 'near fire'.