y fine on power up but become erratic after operation 11
Controller resets itself during cycles .... 11
Display blanking out .. 11
No display at all . 12
Programming malfunctions .... 12
Button or buttons dont operate . 12

Vacuum Related Malfunctions
Pump wont turn on . 13
Pump wont turn off 14
Intermittent pump operation ... 14
Solenoid wont open or close .. 15

Technical Data Sheet
Heater resistance ... 16
Parallel combination of heaters .... 16
Sensor resistance at various temperatures .... 17
Solid-state relay operational voltages ... 17

Picture References
Control Panel . 6
Solid-state relay ... 18
View of access panel ... 18
Power Board 19


2 OVERVIEW


Please read the entire owners manual and fully understand the proper operating
procedures before continuing the trouble-shooting guide.

Each Bienfang
®
Vacuum Press is fully assembled, calibrated, and tested at the factory to
pull a high level of vacuum in a minimum amount of time. Once passed by the Quality
Control Department, the completely tested press and pump are packaged and shipped
together to ensure that each customer receives a complete and tested unit.

However, during shipping and uncrating, the alignment of the top and the base of the
press may be altered. To ensure proper alignment of the press, refer to page 5 of the
Owners Manual for instructions.

If problems persist, or questions arise after referring to this guide, please contact
Bienfangs Technical Service Department at 1-888-240-6021.


















3 HEAT RELATED MALFUNCTIONS


Run Away Heat Condition With Heat Control Off
Possible Causes:
- Sensor or sensor assembly
- Solid-state relay
- Mis-wired power board assembly (if new installation)
- Mis-wired control board assembly (if new installation)

This section is to be used in the case of presses that experience a severe runaway heat
condition. Use this section ONLY if the press continues to heat up even with the heat
control indicator OFF.

A faulty sensor or a sensor that is pulled away from the platen would cause a run away
condition, however, the rate of change indicated on the temperature display can provide
clues as to whether or not a sensor has pulled away. The display would still indicate
rising temperature although not as intensely.

A bad solid-state relay would also cause the heat to run away. The type of relays used in
the Vacuum Presses normally fail in the on state. The inline heater thermostat switches
will break the heater connection after 350
°F is reached, but then reset after the
temperature drops.

The power board receives an on signal from the controller that turns on the solid-state
relay with 1 transistor. If this transistor is bad, it is possible that the relay will always be
on, however, this transistor would normally fail in the off state leaving the power board
as an unlikely cause of failure in most cases.

The controller measures the temperature from the sensor, then decides if the heaters need
to be on or off based on the set temperature when in heat control mode. If the sensor
input circuitry is faulty it can be diagnosed by disconnecting the sensor and reading the
display as indicated below. The controller sends 1 signal to the power board to turn on
and off the heaters. If this signal is faulty, it can be diagnosed by disconnecting the
controller altogether as outlined.

Non Intrusive Actions:
1.

Power up cold press.
2.

Press heat off button.
3.

Verify heat control led is off.
4.

Does the temperature read out indicate room temperature, then increase at a very
slow rate as compared to the actual platen temperature?
If yes- refer to Press runs hotter than set temperature section
If no- continue


4

5
Does the temperature read out indicate room temperature then follow rising
temperature rapidly?

If yes- sensor is OK.

If no- proceed to Intrusive Actions, Step 5.

Intrusive Actions:
5.

With power off, remove control panel from housing.
6.

Disconnect ribbon cable from control panel assembly.
7.

Power up press.
8.

Does press heat up?
If yes- control panel is OK, proceed to Step 9.
If no- control panel or ribbon cable is faulty, replace both.
9.

With power off, reconnect ribbon cable.
10.

Disconnect sensor harness from back of controller assembly.
11.

Turn power on.
12.

Use a paper clip or a piece of metal to short the two pins on the controller sensor
connector together.
13.

Does the display read less than 50
°F when shorted and over 300°F when opened?
If yes- if sensor was OK from step 5, then continue. Otherwise, stop and
check or replace sensor assembly.
If no- replace control panel assembly.
14.

With power off, disconnect the wire from power board labeled Coil+
15.

Turn power on.
16.

Does press still heat up?
If yes- solid-state relay is faulty, replace.
If no- power board or ribbon cable is faulty, replace both.
17.

With power off, reconnect Coil+ wire.
Press Runs Hotter Than Set Temperature
Possible causes:
-Sensor or sensor assembly
-Control board assembly

This section is to used for presses that experience hotter than normal operating
temperatures. DO NOT use this section for run-away temperature conditions.

A faulty sensor, or a sensor that has pulled away from the platen will cause the
temperature to run higher than normal. If the sensor is not firmly mounted to the platen,
the press will run hot. A controller with a bad sensor input circuit will also cause faulty
temperature control.

Non-Intrusive Actions:
1.

Power up cold press.
2.

Press heat on button and set temperature for 200
°F.
3.

Does the temperature read out indicate room temperature, then increase at a very
slow rate as compared to the actual platen temperature?
If yes- proceed to Step 4.

Does the temperature read out indicate room temperature, then follow rising
temperature
rapidly?


If yes- sensor is probably OK.


If no- proceed to Step 4.

Intrusive Actions:
4.

With power off, remove control panel from housing.
5.

Disconnect sensor harness from back of controller assembly.
6.

Turn power on.
7.

Use a paper clip, or a piece of metal to short the two pins on the controller sensor
connector together.
8.

Does display read less than 50
°F when shorted and over 300°F when opened?
If yes- if sensor was Ok from Step 4, then continue. Otherwise, stop and
check or replace sensor assembly.
If no- replace control panel assembly.


Pictured above is the control panel. The hose goes into the bottom valve.
The sensor and the ribbon cable are also pictured.


6

7
No Heat Or Press Runs Cold

Possible Causes:
-Sensor or sensor assembly
-Control board assembly
-Power board assembly
-Mis-wired (only if new installation)
-Solid-state relay
-Heater safety thermostats

This section is to be used for presses that will not heat up after the heat on indicator
has been verified on and a valid set temperature has been entered.

A faulty sensor or sensor harness that has become opened will cause the controller to
think that the press is too hot, therefore, never turning on the heaters. This can be easily
diagnosed by interpreting the temperature display.

A controller with a bad sensor input circuit or a bad heater control output circuit will also
cause faulty or no temperature control.

The inline heater thermostats may be stuck open not allowing any power to the heaters if
they are wired in series. If they are wired in parallel, then only ½ of the press will get
hot.

Intrusive Actions:
1.

With power off, remove control panel from housing.
2.

Disconnect sensor harness from back of controller assembly.
3.

Turn power on.
4.

Use paper clip or a piece of metal to short the two pins on the controller sensor
connector together.
5.

Does display read less than 50
°F when shorted and over 300°F when opened?
If yes- continue to Step 6.
If no- replace control panel assembly.
6.

With the sensor connected, does the display read room temperature at cold start?
If yes- continue to Step 7.
If no- check and/or replace sensor assembly.
7.

Turn power to the press off and replace the control panel assembly.
8.

Disconnect Coil- wire and connect it to extra ground lug on power board, using
tacking iron ground lug if necessary.
9.

Turn power on.
10.

Does press get hot?
If yes- the heaters and the solid-state relay are good. Replace power board
or control panel and/or ribbon cable.
If no- most likely the solid-state relay is bad. Replace it. There is still
however a chance that the heater have an open thermostat.

8
Temperature Readout Always Reads 35-50 deg F

Possible Causes:
-Sensor or sensor assembly
-Control board assembly

A shorted sensor or sensor harness will always cause this malfunction. A faulty
controller may also cause this problem but can be easily and safely diagnosed.

Intrusive Actions:
1.

Remove control panel from housing. With power off.
2.

Disconnect sensor harness from back of controller assembly.
3.

Turn power on.
4.

Use paper clip or a piece of metal to short the two pins on the controller sensor
connector together.
5.

Do