Replacing thermostat for baseboard heaters

Bchavez

First off nothing is wrong with the current dial knob tstat but I am needing or wanting something more accurate and keeps a more constant temp. (5 degree drop between turn ons are getting old) I have three baseboard heaters hooked up to one tstat. Single stage, 4000 watts total. What do you all suggest and is it as simple as turning the power off and taking the old one off/putting the new one up just like the old? I considered calling an electrician because of a comment the electrician made when the house was built 5 years ago. He says that it takes a certain tstat not just any tstat. Also we have a 2 1500 watt and a 1000 watt heater connected but on 1- 1500 and the 1000 watt heater come on at any given set temp and the 3 rd heater will join in when the tstat is set to a temp of 68 or above. It then will shut off before the other 2, it sure heats up the room really fast but I rarely set it that high because it heats up to 73 with the 5 degree variation. See my dilemma/concerns? Thank you!