Mini-split systems

[JDB3]

When connecting for a mini-split system ( a heat pump system, where one unit is outside & another is typically on the wall inside) most of the time, I connect the outside unit & the a/c guy runs his power/control wire (consisting of a 14/3 w/g cable) to the inside unit, what if any type of disconnecting means could be installed inside ? Thanks.

 

[shortcircuit2]

Put in a toggle switch for a disconnect.

 

[Gregg Harris]

Put in a toggle switch for a disconnect.

Look at the manufacturer's accessories and you should find a three pole toggle switch to use as a disconnect.

 

[augie47]

Locally, most of the E/Cs use a two pole standard wall switch,
It's a whole another for discussion, but you might check the type cable run between the units.
TC, NM, and SO are common, each bringing into play a whole list of possible violations.

 

[SmithBuilt]

Here's what I use. The hvac contractor supplies it as his supply house carries them.

http://www.leviton.com/OA_HTML/ProductDetail.jsp?partnumber=MS303-DSS&section=40132&minisite=10251


I put it in a deep wire panduit plastic box as close as possible to the indoor unit. Sometimes cut it in.

I sometimes wonder if a 3 pole is required as one of the conductors is used for 24 volts only.

 

[Hendrix]

When connecting for a mini-split system ( a heat pump system, where one unit is outside & another is typically on the wall inside) most of the time, I connect the outside unit & the a/c guy runs his power/control wire (consisting of a 14/3 w/g cable) to the inside unit, what if any type of disconnecting means could be installed inside ? Thanks.

Is this resi?

 

[Hendrix]

When connecting for a mini-split system ( a heat pump system, where one unit is outside & another is typically on the wall inside) most of the time, I connect the outside unit & the a/c guy runs his power/control wire (consisting of a 14/3 w/g cable) to the inside unit, what if any type of disconnecting means could be installed inside ? Thanks.

Some will say that if you can loc-out the disco on the outside, then you dont need a
switch on the inside. That leaves the whole "in sight" issue up for discussion.:?

 

[SmithBuilt]

Some will say that if you can loc-out the disco on the outside, then you dont need a
switch on the inside. That leaves the whole "in sight" issue up for discussion.:?

I can't find a code citation to support that method. Although I see some inspectors allow it.

 

[__dan]

In case it has not been mentioned, an inside disconnect for the inside fan must also open the compressor control circuit and disable it. If the compressor runs with the DX coil fan off, liquid refrigerant could pass through the DX coil and end up at the suction side of the compressor, where it could break the compressor when it tries to compress liquid.

Verify this with the manufacturer.

 

[Gregg Harris]

I can't find a code citation to support that method. Although I see some inspectors allow it.

Some locations do allow it, there is no code article to support it.

Depending on the brand of mini split some are wired with catagory 3 and are required to have a three pole HP rated togle switch to break S1,S2, and S3 for both line and control voltage.