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Short version: what circuit should I install in the US for a 240 volt, 15 amp appliance that requires a neutral, and what receptacle and cord should I use?

Long version: I currently have an old gas dryer and am thinking to replace it with a heat pump electric dryer. While some heat pump dryers run off 120 V, many require 240 V. Usually, the installation instructions assume that you have an existing outlet for a 30 amp electric dryer, but I don't and will have to install a new circuit for the dryer.

I could install a 30 amp circuit with a standard NEMA 14-30 receptacle, but the whole point of these heat pump dryers is that they use less power. For example, the spec sheet for the LG DLHC5502_ says that it only needs a 15 amp circuit, and this seems pretty standard for 240 V heat pump dryers.

Screen shot of electrical requirements from spec sheet

A 15 amp circuit would allow me to use smaller conductors and save some money on copper, so that's what I'd like to do. The installation instructions for the LG show that it uses a neutral, so I'd need a plug with a neutral. My first thought was to install a 15 amp circuit with a NEMA 14-15 receptacle and plug the dryer in to that. However, I can't even find a 14-15 receptacle for sale. I can find a 14-20 receptacle for sale, but I can't find a cord to connect the dryer to the receptacle (would need a 14-20 plug on one end and loop or fork terminals on the other).

What's the best solution here? Is it ok to install a 14-30 receptacle on a 15 amp circuit? Does a 14-15 or 14-20 appliance cord exist and I just can't find it?

(Some heat pump electric dryers don't need a neutral, which would make this much simpler because NEMA 6-15 receptacles and appliance cords are readily available. In fact, I think that the Bosch 500 comes with NEMA 6-15 cords.)

lnmaurer
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I don't like to make simple things complicated. Neither should you. As others stated, the difference in cost can be far outweighed by future headaches should you change to a standard dryer needing a 30 amp circuit. ( and current headaches in finding parts).

Since you can run a 15 amp appliance on a 30 amp circuit with 10-3 wiring, but cannot do the reverse, it makes sense to just go with a 30 amp circuit. Then you can use a 14-30 receptacle and cord that are readily available.

Time, trips to various stores, searching the internet and the ability to use a standard dryer is worth far more than the $20 or so you may save in cable.

Also think about what happens if you should try to sell your house. New buyer is looking at how many hundreds if not over a thousand dollars to get 30 amp service for a dryer. The result is they may pass over your home, or least they will discount far more than you may save on cable. Going with 12 or 14 cable is just not a good decision.

  1. update

The installation guide instructs the use of 4 wire #10 AWG cable minimum. See pages 18 and 19 Installation manual

RMDman
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I will try to answer part of my own question: "Is it ok to install a 14-30 receptacle on a 15 amp circuit?"

From what I've read, the answer is "yes". NEC 210.21(B)(1) states that

A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit.

It says "not less than", not "equal to". A 14-30 receptacle has an amperage rating of 30 amps. 30 is not less than 15. Therefore, installing a 14-30 receptacle on a 15 amp circuit seems to be allowed by code --- even if it would be unusual. As weird as it is, it wouldn't be unprecedented. Many electric ranges are on 40 amp circuits but use 14-50 outlets. Also, the specs of the outlet matter; the outlet may specify a minimum wire gauge.

That said, I'm not an expert, and maybe there's some other code requirement that would ban a 14-30 receptacle on a 15 amp circuit. If so, please provide a citation, and I'll update this answer to reflect that!

lnmaurer
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