Compu-Brew, how to calibrate?

I have acquired a Compu-Brew brewing system made by Advanced Brewing Technologies (sample image here: http://www.homebrewchatter.com/home2/galleries/169/motorcycles1_05 018.jpg). ABT is apparently no longer in business. I am trying to figure out how to calibrate the temperature sensor/controller. I figured out during my brew session this morning that the system is about 20 degrees low; set the system for 150, checked my mash with a good thermometer about 20 mins after the system said I hit my temp, and the mash was only at 130. Anyone have any instructions on how to calibrate this system? Thanks much in advance.

I ran into your post as I was looking for the instructions on how to do exactly that. turns out I had them but lost them and need them as well.

So I messed around and figured it out on my own, so here is the procedure

Unplug the control box.
open the control box and locate the two dip switches on the back side of the circuit board.
in 'run' position, both dip switches should be depressed on the hinge side of the switch (hinge of the control box door).
Flip both switches to the outside.
remove the thermocouple from the mash tun and plug it into the control unit.
close the control box and plug in.
turn the power on and you should see 50.0 degrees on the temp set side and -- on the time side LED displays.
Press the temp set button one time, and the time side will display 'LO'.
Insert the thermocouple into a glass of ice water and stir it around until the temperature stabilizes...it may not be 32 degrees, mine settled at 34.6 today.
Press the temperature set button once more.
The time display will show, 'HI'.
Now put the thermocouple in a pan of boiling water and keep it there until the temperature stabilizes, again it may not be 212, mine settled in at 214.5 today.
(in both cases the lo and hi portion of the work, the stabilized temp will still go up and down a few tenths of a degree, but what you are watching for is the temp to stop going down with the ice and stop going up with the boiling water)
Now press the temp control again and it will say 'CL' which means 'calibrate'.
Press the temp control one more time and it returns to '--'.
Turn the power off.
open the control box and set both dip switches back to the run position (lowered on the hinge side of the door).
Now you can test the temp reading by using the ice and boiling water again to verify that your system is reading properly.
(mine read ice water as 31.8 degrees and boiling water as 213.1, close enough as the system is really intended to be most accurate at the mash temps around 150 degrees.)

hope this helps.

I should mention, I have been using this system since 2000 some time and there have been many mashes over the last 12 years. The reason I had to calibrate, was my heating element became a dead short last time I brewed and it kicked off the circuit breaker. right in the middle of a brew of course! I found that the heating element had overheated and melted the foam insulation on the outside of the heater tube!

Fortunately, I had long ago rigged the system with two valves on the outflow side, one to take samples to test for conversion and the other to control the flow into the mash tun. I also used the 'test valve' as my exit valve when sparging. I used an old brew kettle and routed the outflow into the kettle which was mounted at an elevation slightly above the mash tun and ran a hose from the kettle back into the mash tun. then I lit a small flame under the kettle to use that to warm my mash. I have to now manually watch the temperature and turn the gas on the kettle on and off as needed. Until I get a fix for the heating circuit, I am afraid this is what I will be doing. I still like the fact that the Compu-brew can read the temps for me and run the mash paddle to keep the mash from sticking. I may spend the $575 to get the Blichmann tower of power controller to run the gas flame and just forgo the electric heating all together....I haven't decided yet. that may be the best solution in the end if the electronics are fried and I can't find replacements.

I should mention, I have been using this system since 2000 some time and there have been many mashes over the last 12 years. The reason I had to calibrate, was my heating element became a dead short last time I brewed and it kicked off the circuit breaker. right in the middle of a brew of course! I found that the heating element had overheated and melted the foam insulation on the outside of the heater tube!

Fortunately, I had long ago rigged the system with two valves on the outflow side, one to take samples to test for conversion and the other to control the flow into the mash tun. I also used the 'test valve' as my exit valve when sparging. I used an old brew kettle and routed the outflow into the kettle which was mounted at an elevation slightly above the mash tun and ran a hose from the kettle back into the mash tun. then I lit a small flame under the kettle to use that to warm my mash. I have to now manually watch the temperature and turn the gas on the kettle on and off as needed. Until I get a fix for the heating circuit, I am afraid this is what I will be doing. I still like the fact that the Compu-brew can read the temps for me and run the mash paddle to keep the mash from sticking. I may spend the $575 to get the Blichmann tower of power controller to run the gas flame and just forgo the electric heating all together....I haven't decided yet. that may be the best solution in the end if the electronics are fried and I can't find replacements.