Hi,
I've just moved into a redone house and am now noticing a lot of issues. There are two electric baseboard heaters only one of which is wired to a 20 amp breaker. Both heaters are toast. I just bought 2 new heaters, one being an 8 foot 240 volt 8.3 amp baseboard, the other being a wall mounted forced air heater 240 volt 12.5 amp. The wattage of both combined is 5000 watts. My problem is there is only enough room in my breaker box for 1 double pole breaker and my main breaker is only 100 amps. I have little to no electrical know-how, so how do wire and install these two heaters with out tripping my main?

Any help would greatly appreciated. Thank You.

Your main will not be tripping but your 20 amp breaker will. You need a smaller heater or run a new circuit for the second heater.

So even if I up the my breaker to a 30 amp double pole it still won't be enough to power all 5000 watts? I was under the impresion that 30 amps x 240 volts = 7200 watts... and me needing only 5000 watts that would work... is that wrong?

What size wire do you have attached to that 20 amp breaker?

Well the dumbass who wired it the first time ran 14/2, but I got 12/2 to rerun with... I also picked up 10/2 just in case because I wasn't sure..

This might be something you want to save. Wire sizes, gauges, for breakers (http://www.greatinspector.com/faq-elec-wiresize.html)

Well by looking at that (thank you by the way) I'm thinking if I up it to a 30 amp breaker then I definitely need to run with the 10/2 wire. And since the added amperage of both heaters is 20.8 amps that means a 30 amp breaker. My other concern is that the one circuit won't be able to carry the whole load but I don't have any more room for more circuits in the panel. Should the 30 amp breaker with the 10/2 wire be good?

"My other concern is that the one circuit won't be able to carry the whole load " it will carry the load if you have a 30 amp breaker and #10 wire. Were you thinking of something else?

No no just me not knowing much I wasn't sure if that was the correct way of going about it. But I will go with the 30 amp and #10 wire, thank you for your assistance I really do appreciate it.

You may want to wait for Tkrussell to look at this later today, he may have better suggestions or send him a PM