how do you remove (built-in) temp controller from chiller ?

[wizsmaster]

I'm looking to remove the temperature controller from my chiller, so it will always be on when power is on. I'd rather control the temperature with my AC3, than the built-in temp controller on my CW1000 chiller. This is a 120v 1HP chiller.

Can someone lead me in the right direction, or provide instructions on how to go about this?
There are 4 wires + temp sensor on the PCB.

Wire Color (Label on PCB) - Voltage (chiller state)
-----------------------------------------------------------
Black (AC_N) - 120v (OFF)
Gray (HEAT) - 120v (OFF)
White (on "COMP) 120v (OFF) / 2.9v (ON)
Blue (on "COMP") 120v (OFF) / 2.9v (ON)


Wire connect to
-------------------
Black -> Gray & white to fan
-> Blue to Starter (?)
-> "+" power in (positive)
Gray ->Heat Cutoff on copper?
Blue -> Blue on compressor
-> Black on Fan
White -> "-" on power in (negative)





here is the PCB

[wizsmaster]

any help would be appreciated!

Thanks,

marco

[checkinhawk]

cant you just plug it into the dc8,set the AC temps where you want then set the temp on the chiller lower than you want?that should use the AC to control the temp and not the chiller control.the AC will shut the chiller off at its set point and make the chillers stock controller moot i believe.

[wizsmaster]

i've had issues with the built in controllers - i've had one stay stuck on, not shut it off, which wouldn't be such a huge issue in this case, but i've also had one not turn on ... either way ... i'd prefer to bypass the built-in controller & use power to turn on/off the chiller.

[boydx6]

Marco, get with brucem, I think he has it set the way Chris just mentioned.

[ShawnJones]

Could you take another shot of the PCB to include the silkscreen on the lower right connector? I would say that since it looks to be about 22ga wire that it is probably the thermostat senor. If so I would look into putting a VOM across those leads (wire side, not PCB) and very the temp to see if there is a voltage swing. If there is I would either bridge the header pins or create a harness with the appropriate resistor.

Thats just my advise, don't kill yourself or burn down your house, any questions, just ask.

Shawn

[wizsmaster]

yes, the thin paired cable is the temp probe.

[ShawnJones]

Well it's probably a variable resistor, the resistance will either increase or decrease depending on the temprature. Unplug the chiller, put an ohm meter across the black leads (not the header pins) and measure the resistance on the lines, heat or cool the tank and measure the resistance. It should move one way or another. Once you establish the resistance direction based on temprature, create a harness with a fixed resistor from radio shack so the chiller thinks that the water is always hot. Plug your new harness on the header pins and allow the controller to supply power to the chiller as needed.

UNPLUG THE CHILLER FIRST

Hope it helps, let me know if you need any help.

Shawn

[ArminTamzarian]

Why not just set it to stupid cold and let the other controler have its way?

[ShawnJones]

That's what I was thinking but I think checkinhawk said it already. Of course that would be the easiest solution.