We have a dimplex baseboard electric heater. Double pole, series DTK-DP.
Installed by an electrician.

We have it to heat the main room always on high, (except at night) we set it lower.

It worked well for a month or so then it started heating not so well. Seems as if when we put it on high it heats as if it is on medium.

We thought it was the thermostat that was defect so we changed it and it worked well for a short while and now is doing the same thing. Only heating as if on medium setting even though we have it on high setting.

I hope someone can solve this problem.
Thank you!
Louise