Thermostats for Baseboard Heat
Q: Do programmable thermostats work for hot-water baseboard heating?
I've heard that programmable thermostats aren't recommended for hot-water baseboard heating systems. Is that true?
—Stanley Plant, Franktown, Colo.
Richard Trethewey replies: Not anymore. A number of manufacturers make programmable thermostats—the kind that automatically turn the temperature down at night and up in the morning—that are compatible with hot-water hydronic systems. The key is to get a thermostat that works with your boiler's control wiring. A good heating contractor who's familiar with hydronic equipment can tell you what your options are.
Keep in mind that a boiler-based system won't respond as quickly as a forced-hot-air furnace when the temperature in your house changes. You'll probably have to set the thermostat to turn itself down at least an hour before you want a noticeable drop in temperature at nighttime. Likewise, set the thermostat to turn up the heat at least an hour before you get up in the morning. You may have to fiddle with the timing a few times before you determine how long it takes for your house to heat up and cool down.
By the way, these thermostats are not a good match with hydronic radiant-floor heating systems, which take even longer to warm up and cool down than baseboards. It's generally not worth programming a thermostat to raise and lower floor temperatures on a daily basis.