ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals

>> Home   >> Electrical-Photos   >> Classifieds   >> Subscribe to Newsletter   >> Store  
 

Photo of the Week:

100 Year old Lightbulb
100 Year old Bulb

Advertisement:-Left
Recent Gallery Topics:
What in Tarnation?
What in Tarnation?
by timmp, September 10
Plumber meets Electrician
Plumber meets Electrician
by timmp, September 10
Who's Online Now
0 members (), 163 guests, and 24 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#222376 10/19/23 02:52 PM
Joined: Oct 2023
Posts: 1
A
New Member
Hi! Would love your input.

We recently renovated a condo. The condo building main breaker panel is 150 amps, the panel in the condo unit is 200 amps. The electrician who installed it didn't think that was an issue, but there was a 2 stage HVAC system installed. He only hooked up one stage because he was worried that if the 200 amp panel tripped it would trip the system for the whole building. The heat hasn't been keeping up in the winter because the other stage isn't hooked up. The new electrician thinks he can hook up the second stage without the breaker being tripped.

I can't find the code section that would relate to connecting a 200 amp panel to a 150 amp panel. Are there any code issues here or things we need to worry about?

Thanks

Last edited by A_Boardwalk; 10/19/23 02:52 PM.
Horizontal Ad
Joined: Jul 2004
Posts: 10,008
Likes: 37
G
Member
The real issue is the load calculation. The 150a will be the one that trips and the 200 in your sub panel is just going to be a disconnect.. I am guessing the conductors in the feeder are sized to the 150a breaker in the up stream panel. The 200 should be swapped for a 150 to avoid confusion
BTW I doubt the whole condo is on 150a, that is probably just the feeder to your unit unless this is a fairly small building.
I think it is time that you had a more in depth conversation with your electrician to see what is really going on. The second stage (the toaster wire heater) is probably 10kw or 15kw if this is a large unit. What size is the breaker going to the air handler? If it is 60a, a 10kw heater is likely. (assuming the condenser is another breaker)
Your electrician should be able to sort all of this out. It is probably beyond what you can trust an HVAC contractor to know. (Not really their field).


Greg Fretwell

Link Copied to Clipboard
Advertisement:-Right


Tools for Electricians
Tools for Electricians
 

* * * * * * *
2023 National Electrical Code (NEC)
2023 NEC + Exam Prep Study Guides Now Available!
 

Member Spotlight
electure
electure
Fullerton, CA USA
Posts: 4,295
Joined: December 2000
Top Posters(30 Days)
Popular Topics(Views)
340,808 Are you busy
266,179 Re: Forum
247,119 Need opinion
New Page 2
Powered by UBB.threads™ PHP Forum Software 7.7.5