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Steam forced air/AC control scheme.

You can get both systems on one thermostat so long as the stat has both an R and RC terminal. If each system has its own transformer, remove the jumper between R and RC. I'm not so sure you want to mess with delaying the blower motor. That air is room temp, so not that cold. Yes, the high limit is a safety and is necessary. For schmeatics, try going to the manufacturer's website and entering the part numbers of the controls. I happen to know Honeywell's in case you have some of them--http://customer.honeywell.com. Scroll to the bottom right corner of the page and enter the part number, for example, TH6110.


  • Forrest
    Forrest Member Posts: 2
    Steam forced air/AC control scheme.

    I am working on cleaning up an old steam forced air/AC control system in a residence(15lb./250F-District Heating). The system uses two seperate thermostats as the AC was just added. I want to have one thermostat for both heating and cooling. Also I believe I should use a plenum control to start the blower motor when heating to prevent the blast of cold start up air. Also, is the high limit necessary to use? There is a newer five wire low voltage steam control valve being used. Where can I go to get a schematic that will work for this system, and recommended parts. Thanks, Forrest
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