installing new HVAC system wiring

[Brandon]

I am having an HVAC upgrade done soon. My current electric forced air furnace is circa 1979. I am having a heat pump/air handler unit installed next month, and I am trying to save money by performing my own electrical work to install a service disconnect to the outside heat pump unit. It will be just on the outside wall adjacent to the existing furnace in the garage. The heat pump will require 40 amp service, so I had planned on running some 6/3 romex from the main breaker panel to the new service disconnect. the main panel is on the opposite wall of the garage (of course), and the walls are finished so this would require a 40 foot run of conduit to the location of the outside heat pump disconnect panel.
The existing furnace has two separate 60 amp circuits servicing what I am assuming are the fan and the heating elements. There are also two 60 amp breakers on the furnace panel functioning as the service disconnects. I think the new air handler unit will likely only take 40 amp service.
I was wondering if I could just "re-route" one of the 60 amp disconnects to make a short run (probably 6-8 feet max) for the outside disconnect panel for the heat pump (which only needs a 40 amp service). disclaimer: I'm a relative novice to electrical DIY, so I apologize if my terminology is incorrect. I've done my share of rewiring for outlets, lighting, and even a clothes dryer but nothing like this.
any input and guidance would be appreciated!
thanks,
Brandon

 

[user 4883]

Unfortunately, this is not a project where you will be able to save money by doing some work yourself.
The work you propose requires a permit and an inspection.
The work you propose is already part of all quotes you get for the install.
No licensed tradesperson will attach to your work as he doesn't know what was done and if correctly but, now must put your work under his license and warranty it.
NOT GONNA HAPPEN!

 

[hornetd]

You may be able to get a homeowners permit to do that work. Most localities that issue home owners permits; although certainly not all; would require that you pass a homeowners electrical examination so you would have to study up on the Electrical code for one and two family dwellings. The sizing of branch circuit conductors and Over Current Protective Devices (OCPD) for Heating Ventilating and Air Conditioning is different than many other loads. You could waste a lot of time effort and money installing markedly larger circuits than you actually need. You would need to know the OCPD size and the Branch-Circuit Selection Current (BCSC). for the new equipment in order to size the new circuits. Both of those values are found on the listing label of the equipment itself. If you can learn the manufacturer and the individual model numbers of the equipment to be used some manufacturers will have the information at their web site. No one here is going to be able to provide specific guidance without that information. It might be wise to decide this project is out of your depth and let the contractor do the installation. For your own safety insist that they post a copy of their electrical permit before work begins to make sure that they are not doing that portion of the work without a permit. In some places a mechanical permit is also required. If the system will include fuel gas installation they will also need either a plumbing permit or, in many places, a fuel gas fitting permit. Each of those may require a separate License in order to draw that permit. If you call your local code enforcement office they will tell you which permits have to be drawn for the work you are having done. I've never known code offices to ask your name or address before speaking to you but my experience is not likely to cover your locality. Good Luck with your project.

--
Tom Horne

 

[WyrTwister]

Sounds like your existing furnace was resistance heat only ? With 2 60 amp circuits .

Did you not have an A/C condenser ? If you did & you are not up existing equipment , the existing condenser circuit may be adequate for the new HP condenser .

Your new " furnace " will also likely come with electric heat strips for emergency heat and for use when the HP is in defrost mode . Find out what amperage electrical circuits are needed for the HP condenser & the furnace and then go from there . You may be good to go as is .

Wyr
God bless

 

[hornetd]

Unfortunately, this is not a project where you will be able to save money by doing some work yourself.
The work you propose requires a permit and an inspection.
The work you propose is already part of all quotes you get for the install.
No licensed tradesperson will attach to your work as he doesn't know what was done and if correctly but, now must put your work under his license and warranty it.
NOT GONNA HAPPEN!

If he were to get a Homeowner's Permit then they should be fine. Forcing a homeowner to purchase additional services from them would violate most States' Home Improvement Regulatory Acts.