I am not sure exactly how your theromstat is connected, but I suspect everytime your theromostat is calling for heat, the back up electric heat strips are turning on. Using the electric heat strips is much more expensive than the heat pump. This configuration should only be used as a temporary work around until the heat pump can be fixed.

Is the contractor who told you to rewire the theromstat the HVAC company who will service the heat pump? If not have you called a reputable HVAC service company?

It is the same contractor that told me this. I want a fix not a patch

He also suspects the thermostat is faultyfaultyfaulty...

It is possible but I’m skeptical it is the thermostat.

Could be the thermostat but more likely he wired it incorrectly. Note that some older thermostats require W1 and Y1 to be jumpered, but don't do this unless the instructions tell you to do so.

• Bosch BOVA Heat Pump Installation Instructions
• Bosch BC100 Thermostat Installation Guide

Pages 16+ shows how a thermostat can be wired to the BOVA. What terminal on the (a) thermostat and (b) BOVA is each colored wire attached to? Based on what you wrote, jumping W2 to W1 on the indoor unit allowed power to flow to W on the outdoor unit which is auxiliary heat. Seems odd that W1 wasn't wired while W2 was wired as W1 is first-stage auxiliary heat and W2 is second-stage auxiliary heat.

Power to Y1 and Y2 turns on the compressor for stage-1 and stage-2 heating, respectively. If the compressor isn't running even though heat is on, the outdoor unit will be quiet. Is that the case?