INSTRUCTIONS CONVERSION FROM FAHRENHEIT TO CELSIUS ON DIFFERENTIAL CONTROL MODELS

Transcription

1 Buy Winston service parts online! Factory direct at I N D U S T R I E S INSTRUCTIONS CONVERSION FROM FAHRENHEIT TO CELSIUS ON DIFFERENTIAL CONTROL MODELS All HA4 Series holding cabinets are shipped with the controls set to display degrees in Fahrenheit. This instruction explains the procedure for changing the default temperature display from Fahrenheit to Celsius. TOOLS NEEDED: Phillips Head Screwdriver #2 Small flat blade screwdriver 11/32 Nut Driver 9/16 Nut Driver PROCEDURE: Save all screws, nuts, and spacers removed. They will be re-used. 1. Disconnect all power to unit before attempting to service. If you are unsure how to disconnect unit consult a qualified electrician. 2. Unscrew the control panel from the cabinet (4 screws). MAKE SURE YOU HAVE GROUNDED YOURSELF TO REMOVE ANY STATIC ELECTRICITY FROM YOUR BODY BEFORE TOUCHING ANY CIRCUIT BOARDS. 3. Pull the control panel out from the cabinet being careful not to pull too far. Rest the control panel's lower edge on the cabinet. Disconnect the 2 probes from the rear of the control panel by pulling the white connectors apart (2 connectors). BE SURE TO GRAB THE CONNECTOR ONLY - DO NOT PULL BY THE WIRES. Page 1 of 5

2 4. Disconnect the large black wire connector from the rear of the control panel by pulling the connector apart. BE SURE TO GRAB THE CONNECTOR ONLY - DO NOT PULL BY THE WIRES. 5. Using 11/32" nut driver, disconnect green and yellow ground wire. 6. Take the knobs (2) off of the front of the control panel by undoing the screws on the knobs. Use a small flat blade screwdriver (a calibration screwdriver works well) to loosen the screw on the side of each knob. Page 2 of 5

3 7. Using the 11/32" nut driver, remove the nuts (4) that secure the power board to the control panel. 8. Make sure you have grounded yourself to remove any static electricity from your body before touching the circuit board. Carefully grab the power board by the sides and lift up. Be careful not to bend the metal pins located under the connector as shown. Lay the circuit board aside on a static-free surface. BE CAREFUL NOT TO BEND PINS UNDER CONNECTOR. 9. Remove the aluminum tube spacers that are on the studs (4) and set aside. Remove the aluminum cover. Page 3 of 5

4 10. Remove the spacers that were left on the studs under the aluminum cover and set aside. Remove the control knob retainer nuts using the 9/16" nut driver. 11. Make sure you have grounded yourself to remove any static electricity from your body before touching the circuit board. Remove the main circuit board. Be careful not to touch components on the board. Lay it aside on a static-free surface. 12. Install the micro-shunt (jumper - part number 09059S01) as shown. It fits over the first two pins (pin #1 is identified on the circuit board). The shunt only fits one way (with the gold colored metal piece facing up) so be careful not to force it. INSTALL MICRO- SHUNT ON FIRST TWO PINS. Page 4 of 5

5 13. Re-assemble the control panel by following the above steps in reverse order. Before performing step #11, place spacers on the control panel studs as shown. HOLE LONG SPACERS SHORT SPACERS 14. As part of the re-assembly process, remember to re-install short spacers on the studs on top of the aluminum cover in step #8 before re-installing the power circuit board. Also in step #8, be careful to position the connector over the pins and press down gently to seat the board in place. 15. As part of the re-assembly process (step #3 above), hook the probes back up to their terminals as shown below. The probes are marked 'A' for air and 'W' for water on connectors inside the cabinet. As you are facing the cabinet, the 'A' Air probe connects to the far right terminal and the 'W' Water probe connects to the middle terminal. The far left terminal is not used. EMPTY 16. Check all terminal connections and make sure all screws have been tightened. END Page 5 of 5