Need 2nd Opinion

[Chamuit]

I'm helping my BiL.

He's trying to hook up a 3P A/C and the L1,L2,L3 aren't clearly marked.

From the picture he sent me here I am guessing that the lugs on the top of the right hand contactor are where his wires are to go. He'll double check with the wiring diagram when he gets back there but would like some additional educated guesses.

The unit is a York ZH150N15 if you are familiar with York.

 

[norcal]

My guess also that the line leads would go on the contactor on the right, otherwise you have multiple conductors under 1 lug, factory wiring as shown does not count IMO. What does the wiring diagram say?

 

[JES2727]

Yes, I would agree that the supply wiring is to terminate on the lugs on the top of the contactor on the right.

 

[ty]

Yes, I would agree that the supply wiring is to terminate on the lugs on the top of the contactor on the right.

another vote for contactor on right.

 

[eric9822]

Are the contactors upside down or is the picture upside down?

 

[KP2]

I vote top right as well.

 

[LarryFine]

Are the contactors upside down or is the picture upside down?

If it's the latter, I vote for the bottom-left terminals.

 

[220/221]

L1,L2,L3 aren't clearly marked.

Thery are surely marked on the diagram.

It looks like the 3 open lugs would be the obvious choice.


When he turn the unit on, have him listen closely to it. A 3phse compressor makes a lot of noise when it runs backwards :roll: A few seconds won't kill it but it won't help it any.

 

[TOOL_5150]

I vote top right, with orange being L1

~Matt

 

[LarryFine]

A 3phse compressor makes a lot of noise when it runs backwards.

From what I've heard, AC compressors aren't phase-direction-sensitive, although ancillary equipment may be.

 

[JLCELEC]

I agree they should be wired to the contactor on the right. My guess is that this is a start run contact for a motor of some sort.

 

[e57]

I would read the schematic on the door and identify the component where they would go... Then again - I'm an 'lectrician... And depending on your point of veiw - a qualified people.

 

[ceb58]

From what I've heard, AC compressors aren't phase-direction-sensitive, although ancillary equipment may be.

Scroll compressors usually dont care on rotation. A rotary compressor is directionally sensitive. But as you said the ancillary equipment may be.

 

[R Bob]

From what I've heard, AC compressors aren't phase-direction-sensitive, although ancillary equipment may be.

For the most part, and in this application, that is true.
A more critical check of phase rotation is to make sure the blower and condenser fans are turning in the correct direction.

 

[R Bob]

Scroll compressors usually dont care on rotation. A rotary compressor is directionally sensitive. But as you said the ancillary equipment may be.

Scroll compressors are rotation sensitive.
Most of the large ones have phase monitoring and lockout, otherwise, the only reliable way to postively confirm rotation is to make sure that the suction pressure is dropping and the discharge pressure is increasing on start up.

 

[DavidA]

Yeah, right hand contactor with L1 - L3 right to left.