I currently Have one Honeywell programmable thermostat, two wire hooked up to two baseboard heaters that are 240 V. The thermostat controlling these two baseboard heaters equals 3500 W max now what I am looking at trying to do is also install a fan forced heater which I would have set for 700 W going on the same 12 gauge wire Now the thermostat that would be powering the fan forced heater would have to be pigtailed or daisy-chained chain.

The breaker is 20 double pole. The 2 baseboard heaters are 6’ 1500 each.

  • 1
    What size is the breaker - 15A or 20A or more? What size are the existing baseboard heaters? (Watt or Amp rating - no other measurements really matter. If you can't find a Watt or Amp rating on the heaters or model #s then there are ways to figure it out with a multimeter.) Dec 3, 2023 at 3:01
  • Hello the breaker is 20 double pole the 2 baseboard heaters are 6’ 1500 each the new fan forced heater is set for 700w that I would install a 2000w max thermostat to. and they all would be on 12-2 wire so I’m trying to figure out if this 2000w stat daisy-chained will work or is there going to be too much current on it
    – Bryan
    Dec 3, 2023 at 5:22

1 Answer 1


A 20A 240V circuit can provide 4,800W of power. However for continuous use such as heaters it is derated to 3,840W (80 %).

With 2 x 1,500W = 3,000W that leaves 840W available. A 700W heater fits, with very little room to spare.

  • That is correct but if I have 2 - wall thermastats (on the same power feed) side by side one maxed at 3500w connected to the baseboard heaters and another one pigtailed to another box with a thermostat that is rated for 2000w and then to the wall heater? - would there be 3700w current flowing to both thermostats or because they are pigtailed it would only be the wall heaters current flowing through?
    – Bryan
    Dec 3, 2023 at 16:05
  • Assuming everything is wired correctly, each thermostat will only carry the power needed for the heaters it controls. In fact, if it is wired incorrectly so that thermostat A controls heaters A and heaters B then thermostat B will not function as expected. The thermostat rating is similar to the breaker rating - a maximum. But a breaker actually uses very little power itself (none for a plain breaker and milliamps for a GFCI or AFCI breaker) and a thermostat uses very little power itself (none for a bimetal thermostat, milliamps for a electronic or smart thermostat). TL;DR no problem. Dec 3, 2023 at 16:10

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.