HVAC condenser not wired properly?


Old 01-13-13, 02:49 PM
Thread Starter
Join Date: Jun 2012
Posts: 37
Received 0 Votes on 0 Posts
HVAC condenser not wired properly?


I had an electrician come out to inspect my panel and provide an estimate for some additional circuits. He noticed that the HVAC condenser was connected to a 40A two-pole breaker with #10 wire (2x#10 w/G).
He stated that #10 wiring should be protected by 30A breakers, that a 40A circuit should use #8 wire, and that the present condenser wiring may be dangerous and a serious violation of the NEC.
The HVAC system is a recent upgrade/replacement for a 33-year-old system. The original condenser wiring was used to connect the new condenser. Sometimes the original 30A breaker has tripped.
The installer sent out a service technician who replaced the original 30A breaker with the current 40A breaker. It has not tripped.
The electrician recommended that I have another HVAC company inspect the HVAC wiring and determine what should be done. He would then be happy to provide an estimate of the cost to repair any sub-standard wiring.
The identification sheet on the condenser shows the following information:
LENNOX M/N: XC17-048-230-03
Electrical Rating: 1 PH, 60 HZ
Nominal Volts: 208/230 Min 197 Max 253
Compressor PH: 1, RLA: 21.8, LRA: 117
Fan Motor PH: 1, FLA: 2, HP: 1/4
Min. Ckt. Ampacity Amperage Minimum: 29.3
Max Fuse or Ckt. Bkr. Fusible/Coupe Circuit (HACR per NEC): 50
Can anyone determine from the above information if the condenser is not properly wired and/or not wired to Code?
Thank you for your time and expertise,
Sponsored Links
Old 01-13-13, 03:51 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: Twin Cities, MN
Posts: 12,933
Received 54 Votes on 47 Posts
#10 wire should not be on a 40 amp breaker. Changing out the breaker from a 30a to a 40a should not have been done without increasing the wire size.

As you can see by the Min Ckt Amps the circuit is undersized. It should be a 40 or 50 amp circuit. Replacing the wire is the best course of action here. If it is conduit, this would be rather easy as you would need 2 - #8THHN and 1 #10 ground. If it is cable, you would need to replace the cable.
Old 01-13-13, 05:43 PM
hvactechfw's Avatar
Join Date: Jan 2011
Posts: 6,245
Received 0 Votes on 0 Posts
agreed! ^^WHAT HE SAID^^

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes
Ask a Question
Question Title:
Your question will be posted in: