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 All this is superseded by whatever manufacturer requires.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 All this is superseded by whatever manufacturer requires.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

2011 DODGE CARAVAN (INOPERABLE) (A53843)
2011 DODGE CARAVAN...
2014 FREIGHTLINER  CASCADIA (INOPERABLE) (A53843)
2014 FREIGHTLINER...
2001 J ODell 16ft Enclosed T/A Trailer (A51691)
2001 J ODell 16ft...
2010 Ford Edge SE SUV (A51694)
2010 Ford Edge SE...
2008 FORD F450 SERVICE TRUCK (A54607)
2008 FORD F450...
500 BBL FRAC TANK (A53843)
500 BBL FRAC TANK...
 
Top