I need an opinion from a HVAC tech.

If you're a HVAC tech please chime in.

I have a central air with heat and ac that is on a wi-fi thermostat. I like the convenience that can adjust the setting if needed from my phone or pc.

I have a 25 PDVC that I've just installed a programmable thermostat. I used this stove a lot to supplement my central heat.

I would like to intall a wi-fi thermostat on it as well but I don't have a common wire from the stove.

Can I tap the common wire from my central air?

I was thinking until just a moment ago that it could be done, though counter indicated, but now I'm against it. It could be done by bringing both neutral and common, then running neutral and a switch to the new furnace, but there are ground loops and possible differences in phase and whatnot. I wouldn't do it.
Btw, I'm not an hvac or anything, I'm a mechanical engineer (jack of all trades).

Problem solved. I just found out that Hunter wi-fi thermostat does not need a C wire, it's battery powered.