HVAC equipment wiring issue.

Originally Posted By: dandersen
This post was automatically imported from our archived forum.



http://www.nachi.org/bbsystem/usrimages/D/DSC03633.JPG ]


My problem is that there are breaker knockouts on the front cover of the air handling unit but there is no place to install circuit breakers. Normally, a heat pump has separate circuits for the heat kit and the control/fan circuits. This unit has a 30 amp, 240 V breaker on the other side of the house which will unlikely trip in the event of motor failure.

[ Image: http://www.nachi.org/bbsystem/usrimages/D/DSC03636.JPG ]

Is this an equipment designed flaw?

There is a terminal block on the heater kit and all lower amperage circuits come off this terminal block and there is no way to seperate these circuits from seperate pulls from the disconnect box.

What are your interpetations of this wiring and equipment configuration?


Originally Posted By: Greg Fretwell
This post was automatically imported from our archived forum.



It’s a Junkatrol, big surprise.


You can probably find the breakers that fit those knockouts. They will be wired via screw terminals in the back.


A lot of stuff goes on under the covers of listed equipment that you couldn't do yourself. If it doesn't catch fire during the test in the lab it is OK.

IBM 3803 M2s have 14ga cables that run around under the floor with a 100a O/C device as the first means of protection. Stupid, but listed.