HVAC disconnect question

   / HVAC disconnect question #21  
Here we go, over thinking again. The old adage KISS applies here!
 
   / HVAC disconnect question #22  
Well, ive been doing commercial and industrial electrical for 35 years. All our motors have a fused disconnect. And all motor control panels have multiple fuse protection devices along with heaters . Breakers are always rated 125% over motor loads. Offer limited protection .


but i digress from OP. The states i work in require that we follow nameplate on device. For instance my AC unit has a nameplate that states minimum fuse size. I HAVE to use fuse. If label says minimum OCPD (over current protective device) then you can use a breaker. All this is superseded by whatever manufacturer requires. Most A/C Manufacturers install paperwork i used to read REQUIRED a fused disconnect, so it was never an issue.
 
Last edited:
   / HVAC disconnect question #23  
Well, ive been doing commercial and industrial electrical for 35 years. All our motors have a fused disconnect. And all motor control panels have multiple fuse protection devices along with heaters . Breakers are always rated 125% over motor loads. Offer limited protection .


but i digress from OP. The states i work in require that we follow nameplate on device. For instance my AC unit has a nameplate that states minimum fuse size. I HAVE to use fuse. If label says minimum OCPD (over current protective device) then you can use a breaker. All this is superseded by whatever manufacturer requires. Most A/C Manufacturers install paperwork i used to read REQUIRED a fused disconnect, so it was never an issue.
I have had a number of corrections (from inspectors) due to the manufacturers label saying minimum fuse size, and then being required to install a fused disconnect to pass inspection.
If it states minimum OCPD (overcurrent protection device), then a breaker in the panel can be the protective device and non-fused cheap disconnect can be installed next to the HVAC unit.
 

Tractor & Equipment Auctions

MURRAY PUSH MOWER (A53843)
MURRAY PUSH MOWER...
2018 GENIE GTH-636 TELESCOPIC FORKLIFT (A52706)
2018 GENIE GTH-636...
2024 JOHN DEERE 8R 280 LOT NUMBER 8 (A53084)
2024 JOHN DEERE 8R...
EXCAVATOR GRAPPLE (A53843)
EXCAVATOR GRAPPLE...
Blue Concrete Test Shed (A52377)
Blue Concrete Test...
2016 CATERPILLAR 730C2 OFF ROAD DUMP (A51246)
2016 CATERPILLAR...
 
Top