Heat Pump Overcurrent Protection Proper


To All,

I have a quick question about the overcurrent protection regarding the condenser unit. The unit outside is listed for 35 amp max. and the breaker at the main panel is a 30 amp breaker. The service switch/ safety switch near the outdoor unit is a 40 amp breaker. Is this correct for the switch to be rated higher than the in-panel breaker? I believe it is since it should only be used as a service switch for repairs/ replacement. I am just looking for confirmation to my initial thoughts.

Thanks in advance!

What you are calling a service switch is simply a disconnect around here. Regardless the lower rated breaker (main panel) will trip first. Rating of the disconnect is insignificant unless it is lower than the breaker in the main panel.

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Thank you Sir. I was thinking that, but wanted to make sure.

Related to this; I am calling out Larger than recommended Breakers on at least 1/3 of my reports. (and yes I check both the breaker at the panel and also if it has a breaker at the Equip. Disconnect.) Our local “code inspectors” started checking this on final inspection only about 3 years ago because there have been fires associated with this.

Very common here on any home older than three years. The reason is (New Const.) the electrician has no idea what the condenser is going to call for as the Max, so a 50amp is their best guess, and he is done…The Condenser is the last component to be installed and in Utah an HVAC Tech can’t change out a breaker at the panel unless also a licenced electrician. On replacement units most use way less energy than the OEM and Max breaker again is not changed out by the HVAC guy in most cases.

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Yes, the lowest rated breaker is the one to pay attention to. Sometimes the difference in breaker ratings is due to the exterior coil being changed out because of age related failure.