Older dryers not needing a neutral?

[sw_ross]

I’m assuming old dryers have always needed a neutral? Isn’t the motor 120v even if there aren’t any fancy controls.

Had a customer that had an older dryer that went bad. The landlord chose to replace the old dryer with new.
The new dryer wouldn’t work when plugged in so they had an appliance repair person come check the new dryer. He said there’s an issue with the circuit/receptacle.
I went a checked it out and it appears that there is no neutral/ground (older 3-wire). The landlord is wondering what changed with the circuit and how/why did it coincide with getting the new dryer?

I had wondered if the old dryer (they said it was really old!) didn’t need the neutral? Maybe the circuit was like this for awhile? But now I’m thinking that the neutral was gradually lost and that’s why the old dryer stopped working.
The circuit is run in 1/2” EMT for a long run. It only has 2 hots, using the conduit for the ground/neutral. I’m thinking maybe a coupling or something gradually loosened up?
Im planning on pulling a 3rd conductor through the conduit for a ground/neutral.

 

[qcroanoke]

I’m assuming old dryers have always needed a neutral? Isn’t the motor 120v even if there aren’t any fancy controls.

Had a customer that had an older dryer that went bad. The landlord chose to replace the old dryer with new.
The new dryer wouldn’t work when plugged in so they had an appliance repair person come check the new dryer. He said there’s an issue with the circuit/receptacle.
I went a checked it out and it appears that there is no neutral/ground (older 3-wire). The landlord is wondering what changed with the circuit and how/why did it coincide with getting the new dryer?

I had wondered if the old dryer (they said it was really old!) didn’t need the neutral? Maybe the circuit was like this for awhile? But now I’m thinking that the neutral was gradually lost and that’s why the old dryer stopped working.
The circuit is run in 1/2” EMT for a long run. It only has 2 hots, using the conduit for the ground/neutral. I’m thinking maybe a coupling or something gradually loosened up?
Im planning on pulling a 3rd conductor through the conduit for a ground/neutral.

By code you need to pull a neutral and use the emt as the ground if it's continuous. Change it to a 4 wire receptacle, 4 wire cord and remove the jumper bettween the frame ground and neutral. All code requirements.
The old dryer probably worked because it was all mechanical and was getting enough of a neutral reference through the emt to work.

 

[ptonsparky]

The conduit continuity is already suspect. Pull 4 wires.

 

[LarryFine]

The circuit is run in 1/2” EMT for a long run. It only has 2 hots, using the conduit for the ground/neutral.

That was never okay! The old three-wire major-appliance circuit allowed the neutral to do double-duty as the equipment grounding, and not the other way around. Thus, a conduit alone was never allowed to be used as a neutral conductor.

With a break in the conduit, the dryer's cabinet and the conduit on the load side of the break are both energized. You need to add an insulated neutral, and either keep the three-wire circuit or re-wire it for four, and repair the conduit break.

 

[qcroanoke]

The conduit continuity is already suspect. Pull 4 wires.

Will 4 10's fit in 1/2? If It's legal I wouldn't want to pull it.

 

[Dennis Alwon]

Will 4 10's fit in 1/2? If It's legal I wouldn't want to pull it.

Yes it will--I wonder whether the conduit is complete. OP, did you test continuity on the ground. Did you test your voltages anywhere? If the raceway is solid then I would run 3 #10 and use the raceway as an equipment grounding conductor.

Before doing all that make sure the breaker is putting out 240V across the hots and check the conduit for continuity as I stated earlier

 

[ptonsparky]

Will 4 10's fit in 1/2? If It's legal I wouldn't want to pull it.

I never checked, but I would be using stranded and lube with a healthy helper pulling, if it did.

 

[ActionDave]

Four 10AWG thhn will pull in 1/2" emt just fine, it's only 28% fill.

 

[qcroanoke]

Four 10AWG thhn will pull in 1/2" emt just fine, it's only 28% fill.

Definitely would pull 2 out and 4 In. Or run 10-3 w/g if possible.

 

[ptonsparky]

It might be wise to pull one conductor out, examine it for heat damage and see if you can locate the area on the conduit...make sure it doesn't have some rough spots in it.