ERE
I'm using a 200a service entry switch with load shedding and want to connect a Daikin split system with two compressors and 4 inside units to the AC load shed contacts. The problem is that the Daikin units don't use a T-stat control system.. They have rf remote controls only. The only connections between the inside and outside units are three wires (plus a ground) that are not identified as to purpose. From the schematics I can find on the web, it appears that the inside unit is powered by the outside unit. They are inverter units to control fan and compressor speeds. Everything is on PCBs with no clue where functions live.

Anyone dealt with this problem before?
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Birken Vogt
I typed Daikin AC load shed into search and got a couple PDFs for some module. It might be an optional device but it definitely has a load shed input. No idea if it is the right thing or not. Take a look and see if it makes any sense to you.
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ERE
I've tried that and other search combinations on the web but no joy. I can pull up pdf files with installation manuals and repair manuels for the Daikin units, but I don';t see anything in them that helps.
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ERE
I just got off the line with Daikin and the tech people said that there isn't any way to do load shedding with contacts. I guess my option is to go to install a smm for each unit.
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78buckshot
The Daikin ductless splits don't have ac control signals, they have dc modulating controls and communicate between the indoor and outdoor unit. The same holds true for Sanyo, Mitsubishi, Carrier/Bryant, and probably the rest of similar units.
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patmurphey
What happens to the rest of the system if you just cut line voltage to the outdoor units? Then what happens when you restore it? SMMs can do up to 50amps.
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78buckshot
The SMM should work ok, as long as the "thermostat" is not a hard wired remote. Most of the residential units use a wireless remote control (thermostat) with batteries and that won't be affected by a utility loss. When utility is restored the outdoor and indoor units will re-establish communications and take a few minutes to think, they will then follow the command of the remote.
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