Low Pressure Cutout Switch or Suction Transducer Configuration

These units could have either a Low Pressure Cutout switch or a Suction Transducer installed.

The Low Pressure Cutout Switch or Suction Transducer will have the same function, since the unit only has one fitting on the suction tube, the unit can have either a Low Pressure Cutout Switch or Suction Transducer but not both.

The following procedure is to replace a Low Pressure Cutout Switch (LPCO) with a Suction Transducer. To replace a Suction Transducer with a Low Pressure Cutout Switch follow instructions in reverse.

1. Remove LPCO switch from suction tube. Fitting on the suction tube has a Schrader valve in it, unscrew the LPCO.

2. Disconnect the LPCO wires from J9 pins 5 and 6, remove switch and harness from unit.

3. Install a jumper wire on J9 pins 5 to 6.

4. Screw the Suction Transducer on the fitting on the suction tube.

5. Route wire harness into control box.

6. Connect wires to J1 pins 7, 8, 9.

   1. White wire to pin 7.

   2. Red wire to pin 8.

   3. Black wire to pin 9.

7. Secure harness.

Alarm 31 LOW PRESS CUTOUT OOCL only, logged in the data logger

Alarm 120 SUCTION PRESSURE SENSOR ERROR output of sensor outside limits

Alarm 136 TRANSDUCER CIRCUIT ERROR detects no 12V output to sensor

Message 32 LOW PRESS CUTOUT- PLEASE WAIT Suction pressure < 5-11 in. vacuum Message 33 LPCO TIMER HOLD – PLEASE WAIT Suction pressure > 4-7 psig with 30 second delay

If no LPCO or transducer is available for repair, add jumper wire for LPCO or configure transducer NONE.