Keeping steam heat and AC on separate thermostat?

SteamworkS

I thought this discussion had been addressed in the past but couldn't find it in past posts.

I have a one-pipe gas fired steam system for my heat and am getting a Unico small duct high velocity AC system (cooling only) installed. I currently have a Nest controlling my steam boiler. The HVAC contractor would like to have a single Honeywell thermostat control both the steam heat and cooling. Am I correct in remembering that problems can arise when you ask a single thermostat to control two very different methods of heating and cooling? What kind of problems are they and are they usually associated with an electrician who isn't experienced with linking two systems?

Thanks.

Paul S_3

Any capable heating and air conditioning contractor should be a to connect the 2...on the same thermostat ....why not just keep them seperate?

nicholas bonham-carter

The Honeywell Visionpro should be separately configurable for heating and cooling cycles, and would certainly do a better job on the steam control.--NBC

SteamworkS

Thanks guys! I'll go with the Visionpro to see if I can play with the CPH. Does anyone know how that works - would the Visionpro figure out how long it would take to bring the space up to temp and divide that out so that it doesn't satisfy the thermostat too early leaving the homeowner cold waiting for the next hour to begin?

ratio

I had found a tech doc that describes the operation of the VisionPRO stat.