Air conditioning feeders

[Tom G]

Can I put three sets of single phase 120/208 in a race way for three separate RTUs without creating heat if voltage drop is not an issue and pipe is sized probably? Iam trouble shooting a heat problem in an Hvac panel ! Breaker opens and all four Breaks are hot!?

 

[Dennis Alwon]

Sure you can as long as the conductors are sized properly but with heavy loads you will always have heat. That means you have 6 current carrying conductor's so you would have to de-rate 80% of the ampacity of the conductor.

You said 3 RTU's but then said 4 breakers???? How many are tripping, what size wire, and what is the mca of the units.

 

[Tom G]

Yes three sets in one pipe and a 4th in another! One breaker trips often and panel is really warm. Could be length or run. Possibly voltage drop problem.? 350 feet thank you for your reply!,

 

[ptonsparky]

Depends.

Were the wires sized correctly to begin with?

Temperature is subjective.
Could be improperly torque connections at the breaker.
Breaker stabs not making good contact.
Overload due to equipment malfunction.

 

[Dennis Alwon]

Yes three sets in one pipe and a 4th in another! One breaker trips often and panel is really warm. Could be length or run. Possibly voltage drop problem.? 350 feet thank you for your reply!,

350' is a very long distance. What size wire and what is the mca? You very well may have a VD problem...

 

[Tom G]

Depends.

Were the wires sized correctly to begin with?

Temperature is subjective.
Could be improperly torque connections at the breaker.
Breaker stabs not making good contact.
Overload due to equipment malfunction.

Depends.

Were the wires sized correctly to begin with?

Temperature is subjective.
Could be improperly torque connections at the breaker.
Breaker stabs not making good contact.
Overload due to equipment malfunction.

 

[Tom G]

Good suggestion in regards to torque connections. Going to look upon return visit. Thank you

 

[LarryFine]

Are the conductors heavy enough to be conducting heat from within the conduit to the breakers?

You never answered any of our questions about the units' numbers and the wire sizes.