automatic thermostat for steam heat

Mike Minnich

I recently replaced my old (merc switched) thermostat with a new programmable unit (Hunter), in an attempt to save money. I set the temp for 60 at night, and 67 for when we are home, etc, but only two programs per day so not to create too many temp changes. When using the old thermostat, and assuming an equivalent cold day, the system would seem to run every 15-20 minutes, but only for 3-4 minutes. Now, the system seems to run much longer, but not nearly as often. There is an internal adjustment on the old thermostat with numbers on it. Did that have something to do with it? It seems the water in the boiler obviously stayed hotter with the short cycle, but I am not sure which way is better. I may lower the span setting on the new unit to 1 degree instead of 2 to see what difference that makes. Do you think the short cycle is more effecient due to the water and radiators staying warmer? Are there special thermostats for one-pipe steam heat? Please advise. Thanks for the help. (Your book is on the way to my house right now)

thfurnitureguy_4

You want the longer run time. starting and stopping is not an efficient way for your boiler to run. I have the same stat and use the +1 degree setting. You would set the old one to run 1 cycle per hour.