I wrote Mrcool for tech support on fused vs non-fused disconnects...and why their UL placard says 'fuse' in the power supply:
Rick Castleberry (MRCOOL)
Jul 29, 15:57 -05
fuses are very much still in style.it is just a form of a way for better protection especially with HVAC equipment.
If you use an HVAC rated breaker in the house panel you can use just a non fused disconnect switch if your local code allows it. Both meet the NEC but the "Authority having Jurisdiction" is the final word.
EDIT: Now what is really interesting is that the HACR rating is no longer required by NEC for breakers used in HVAC equipment: https://iaeimagazine.org/magazine/2006/11/16/what-do-the-markings-on-circuit-breakers-mean/
Here is another document from Schnieder Electric on the HACR breaker rating (no longer required for HVAC equipment - all breakers meet the original requirement)
https://www.schneider-electric.com/...239.790740779.1564436231-241394369.1564436231
Only the 12K BTU MrCool DIY unit is 110-125v, the other three larger capacity models require 220/240.
If you review electrical code for your locale it's highly likely a dedicated 20a circuit is required, and also a disconnect within reach of the unit for servicing.
We are seeing now that a fuse somewhere in the circuit, or HVAC rated breakers in the panel for said circuit or disconnect box, is required.
Rick Castleberry (MRCOOL)
Jul 29, 15:57 -05
fuses are very much still in style.it is just a form of a way for better protection especially with HVAC equipment.
If you use an HVAC rated breaker in the house panel you can use just a non fused disconnect switch if your local code allows it. Both meet the NEC but the "Authority having Jurisdiction" is the final word.
EDIT: Now what is really interesting is that the HACR rating is no longer required by NEC for breakers used in HVAC equipment: https://iaeimagazine.org/magazine/2006/11/16/what-do-the-markings-on-circuit-breakers-mean/
HACR type –This marking indicates the circuit breaker is suitable for use with the group motor installations typically found in heating, air conditioning and refrigeration equipment. TheNEC2005 no longer has this marking requirement. The electrical industry determined that circuit breakers are considered suitable for use with such equipment without any further testing, therefore, the HACR marking is no longer required on air conditioning and refrigeration equipment or on circuit breakers for use in these applications. The requirement for this marking has also been removed from the UL 1995 product standard for HVAC equipment (see item 3 in photo 1).
Here is another document from Schnieder Electric on the HACR breaker rating (no longer required for HVAC equipment - all breakers meet the original requirement)
https://www.schneider-electric.com/...239.790740779.1564436231-241394369.1564436231
I have two Frederich Breeze models that do not require an electrical box on the outside of the home for power to the unit. The power comes from the inside unit, which is plugged into a wall outlet and travels down with the refrigerant and drain lines in a plastic sheath. I want to add another unit but the Breeze units are not sold anymore and I was wondering if anyone has run wire to their Mr Cool outside unit in the above fashion. I cannot run wire to an outside box without major work I was told by a couple of experts but wall plugs are everywhere.
Only the 12K BTU MrCool DIY unit is 110-125v, the other three larger capacity models require 220/240.
If you review electrical code for your locale it's highly likely a dedicated 20a circuit is required, and also a disconnect within reach of the unit for servicing.
We are seeing now that a fuse somewhere in the circuit, or HVAC rated breakers in the panel for said circuit or disconnect box, is required.
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