Surge protection for minisplit compressor

[scanchain]

I have a minisplit unit for my basement with a disconnect for the outside compressor unit. The outside unit is serviced by 10/2 NM wire.

I want to add some kind of surge protection (SPD) for the outside unit. Maybe like the Eaton CHSPT2SURGE or a plug-in surge breaker. I would need to replace the fused disconnect box with something that can accommodate the SPD (like a 4-space small breaker box).

My question -- the SPDs I looked at all require a connection to the neutral wire, which I don't have in the current disconnect box (since I only ran 10/2 wire, not 10/3 wire).

Any suggestions for me to add surge protection close to the compressor? Thank you.

 

[u2slow]

In what circumstances do you believe the compressor will be closest to the source of a potential surge?

I prefer the whole-house type installed in the main panel.

 

[scanchain]

I already have one SPD in the main panel. I am thinking of adding one at the compressor, it being outside and all.

 

[sberry]

Not sure why you would send it to neutral especially if it's fed from s sub?

 

[scanchain]

Not sure why you would send it to neutral especially if it's fed from s sub?

The SPD has a wire that needs to be connected to neutral. But there is no neutral wire in the exterior disconnect. What should I do with the neutral wire from the SPD? Leave it disconnected?

 

[wyliesdiesels]

Cant say ive ever seen surge protection on an air conditioning compressor

Why do you think you need one when the main panel already has one?

Also, do you get lightning in your area?

 

[scanchain]

Frequent lightning in my area. A google search of "surge protection aircon compressor" will yield many links to recommendations to put SPD on the A/C compressor.

 

[scanchain]

I guess I can buy one of these and I don't need to replace the disconnect. The online image says to connect neutral/white wire from the device to ground. Any comments?

https://www.amazon.com/dp/B008VM6MXI/?tag=atomicindus08-20

 

[Chuckster in NJ]

I have installed several Intermatic COMPRESSOR DEFENDERS and they also protect against brown outs and short cycling. www.supplyhouse.com has them along with other surge protectors.
Protection against "brown outs" was my main concern.

 

[Norcal]

It is the electronics in modern equipment that cause problems, loose a board & the equipment is dead, compressor issues are less likely, although if the compressor craps out, it’s just as dead.

 

[rlitman]

I guess I can buy one of these and I don't need to replace the disconnect. The online image says to connect neutral/white wire from the device to ground. Any comments?

https://www.amazon.com/dp/B008VM6MXI/?tag=atomicindus08-20

I have something like that. Since your AC doesn't use a neutral, it doesn't benefit from N-G protection, so yes, it would make sense to connect the white and green wires from the SPD to the ground in your case.

I have installed several Intermatic COMPRESSOR DEFENDERS and they also protect against brown outs and short cycling. www.supplyhouse.com has them along with other surge protectors.
Protection against "brown outs" was my main concern.

I'm not sure how much inverter compressors need brown out protection. I'd hope it was already engineered in there, but I guess it couldn't hurt.

For my parent's central air, I replaced their contactors with smart ones that have brownout and short cycle protection, and feel that it is certainly worthwhile.

 

[scanchain]

It is the electronics in modern equipment that cause problems, loose a board & the equipment is dead, compressor issues are less likely, although if the compressor craps out, it’s just as dead.

That's the thing. One of the HVAC tech commented that there is more electronics in the minisplit exterior unit versus a regular A/C compressor. That got me on the path to get a SPD for the exterior unit.