I have 5 zones of baseboard heat, 3 of which were disabled due to the addition of a heat pump. The circuit panel is full and would like to restore the operation of the 3 zones of base boardheat.

I was planning on removing 3 double pole 20amp 240 volt circuits and installing 3 QUAD 20 amp double pole 240 volt circuits so that I can restore power to all 5 zones of base board heat. Only I need to order the QUAD circuit breakers and it will take a 1 week or more.

I talked to the local electrical guy at the home center and he said I don't need the QUAD circuits although that would work. Rather then the QUAD he recommended that I purchase 2 20AMP tandem single pole 120 volt circuit breakers for each QUAD that I needed. He said that I could tie them together to get the 20amp double pole that I need. Using this procedure takes 2 single pole breakers and makes them a double pole. But this is not a true double pole breaker. Will that work or should I stick with the QUAD breakers?

Also my base board circuits will need to be extended, I was planning on extending the wire with a wire nut and then taping any exposed copper wire. Is that the best thing to do to extend the wire in the circuit panel?

Do not use the tandem breakers. A true tandem is designed to plug onto only one busbar in the panel. You cannot get 240 volts using one breaker. If you do manage somehow to use two breakers and pull off one leg from each, then the intermnal common trip is non-existant.

Do not take advice from a hardware store clerk.

I know the "quad" breakers you are referring to. They are truly 2- 2 pole 240 volt breakers built into one 2 pole frame. That is the only type of breaker you should use.

Thanks very much for the quick response. I'm going to purchase the 3 quad breakers and go that route as you suggest since it is a pure dual 2 pole solution.