We recently renovated our condo and replaced the baseboard heaters. An licensed electrician did all of the electrical. Now, during a cold snap, the heaters on one thermostat are turning on and off, but the room is not reaching the temperature set on the thermostat. Currently, the thermostat is set to 30℃ yet the room temperature is below 20℃ (need to wear sweater). The baseboard heaters on that circuit will turn on and then turn off intermittently never getting the room to the temp. I would have expected them to run full on until the room was at the set temp.
Some details: We live in a condo which has 208v 3-phase service to the building, 208v single phase to units. The heaters are supposed to be 208v heaters (ordered special from Stelpro). I've verified that the two legs at the thermostat are 120v each. The thermostat is a very basic Stelpro mechanical thermostat.
There are two heaters (1x1500w, 1x1000w) on the same circuit. Prior to renovations, the circuit hosted 3 x ~1000watt heaters (I didn't check them, but they are smaller than the new 1500w heater so that's a guess).
Why would the heaters not stay on continuously till the room is warm enough?