Pairing a oil hydronic system with a 2 stage heat pump

Dave_130

We are replacing an existing AC system with with a new TRANE 2 stage heat pump. The customer currently has a oil hydronic baseboard system and is looking for another choice of heating, hence the 2 stage heat pump. He would still like to use his hydronic heat for the very cold days (20 degrees and below?)and his domestic water heating. We are using a TRANE comfortlink system with a thermostat that is simular to the Honeywell Visionpro. We would have the capability to use the oil heat as the third stage and possibly lock it out at a specific outdoor ambient temperature. The hydronic system, is zoned in 3 zones so I am considering possibly using digital stats to simply control the baseboard heat off of those thermostats and set them a few degrees lower to conterol comfort individually in each area instead of running the total hydronic heat from the main thermostat. Does anyone have any experinece on this application, just wanted some feedback, We had did this before like this but I just thought I would ask. Thanks for your opinion.

Tom Hopkins

Seems like a simple approach.

Rich L.

Outdoor temp sensor

How about using an electronic temperature control like a Ranco ETC112000 to monitor outdoor temperature and lock out the boiler above your 20 degree setting? This way no matter the t'stat setting the boiler wouldn't come on unless it was below the outdoor set point.

Ranco: http://www.myjohnstone.com/ProductDetails.asp?StockNum=L38-383

I've used these before on water to water heat pumps to control an auxilary boiler. We just wanted the boiler to supplement the Geo and not come on until the temps outside dropped below 0. Works great.

Good luck, Rich L