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The MARS 39004 changeover switch is designed for the summer-winter transition of electric thermostats in hydronic heating and cooling fan-coil systems. This switch features color-coded leads for straightforward installation and a sealed SL-8 thermostat for reliable performance.
This switch is ideal for HVAC professionals seeking a dependable solution for controlling climate systems efficiently.
We pulled together the parts most installs need for this unit, plus a few add-ons worth a look. Check what you need — nothing here blocks checkout.
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