Circuit Breaker for your 240vac heat pump

Xringer · 12-22-16, 08:44 PM

When I look at the diagram below, (bottom sensor loop) and see the
overload OLR and the high pressure switch controlling the Power Relay,
(upper right). I see only one side of the 240 vac line is switched..

If the high pressure switch opens, the Power Relay opens only one side
of the 240 vac. Black, ACin1 is opened, but ACin2 is still connected.
I know that 120 volts is still on the main board (relative to chassis ground).

My question is, do we really need a pair of 240 breakers that are mechanically coupled?
I know they make it safer to work on the Outdoor unit,
but I don't think anyone is going to poke around inside an outdoor unit,
without pulling the disconnect hanging on the wall, right next to the outdoor unit..

Besides the safety aspect, is there any other reason to have a mech-coupled breaker pair?
Can't two non-coupled breakers do the job just as well?

12-22-16, 08:44 PM	#1
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Circuit Breaker for your 240vac heat pump When I look at the diagram below, (bottom sensor loop) and see the overload OLR and the high pressure switch controlling the Power Relay, (upper right). I see only one side of the 240 vac line is switched.. If the high pressure switch opens, the Power Relay opens only one side of the 240 vac. Black, ACin1 is opened, but ACin2 is still connected. I know that 120 volts is still on the main board (relative to chassis ground). My question is, do we really need a pair of 240 breakers that are mechanically coupled? I know they make it safer to work on the Outdoor unit, but I don't think anyone is going to poke around inside an outdoor unit, without pulling the disconnect hanging on the wall, right next to the outdoor unit.. Besides the safety aspect, is there any other reason to have a mech-coupled breaker pair? Can't two non-coupled breakers do the job just as well? __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..