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Disconnector for Air Condition

Disconnector for Air Condition

Disconnector for Air Condition

(OP)
Hello,

I'm talking about a normal 12,000 BTU air condition fed from one single phase circuit breaker in a panel board several rooms away.

The NEC (?) state that there shall be a nearby (line of sight And less than 15m) disconnect switch for this kind of deivces.

The Australian / NewZealand code state that this 2 pole disconnect switch can be removed if the breaker feeding the appliance can be secured in the Off position.

I follow all codes at the same time and i have 2 questions:

1. The breaker is a normal miniature 32A, can you please point out one type pf those that can be secured in position? The only ones i know are moulded case type.

2. The HVAC guy tells me Thank you for paying for this to protect me but i don't need it. I ask why and he has a point: he says that the split AC is made of 2 units, one indoor and one outdoor, and i'm installing this near the indoor one so he says when he goes outside to service the radiator, someone might trip this 2 pole disconnect switch inside the room and he will still get electrocuted. So either i install yet a second one for him outside, or forget this idea.

I agree with him and feel that this article is for "window" units. The project is a hospital and we have a whole bunch of those so the savings from taking them out is not negligible.

I would like to ask what do you think? Can a "letter" from the HVAC guy be shown if the "Inspector" comes and asks why doesn't these units have a DP switch (by the way does it Have to be two-pole or just disconnecting the phase is enough, same for 3~, shall it be 3P or 4P for a Y system? I know i can call the Inspector and ask but i want ot know Internationally how ths goes. Thank you.






RE: Disconnector for Air Condition

I'm not sure about codes in New Zeleand or Austrailia. It sounds as though the code is similar to the U.S. National Electrical Code which requires a local disconnect within sight of and reaily accessible from all air conditioning equipment. That includes indoor and outdoor equipment. There is an exception for remote lockable disconnects, only where "the refrigerating or air-conditioning equipment is essential to an industrial process in a facility where the conditions of maintenance and the supervision ensure that only qualified persons service the equipment...". If the equipment is cord and plug connected, the plug may serve as the disconnect.

A letter from the HVAC guy does not satisfy the intent of the code, or protect you from responsibility if someone is hurt. Many types of air conditioning equipment can be obtained with built-in disconnects, but they usually must be specified at the time of purchase.

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