Q: I have a 433 HC with the following problem: When the steam boiler starts to fill, the height probe stops and the contactor is energized and starts to heat up. At this point, everything works normal. The problem starts a few minutes after when suddenly the “FAULT” LED in the control board of the boiler lights up and turns off the contactor. Next, the light goes off and the contactor is energized, and then the FAULT LED lights up and cuts off the contactor. The situation goes on and the steam is not produced. What do you think the problem is?
A: Try disconnecting the leak detection probe from the board and see if it clears the issue.
Reply: The leak detection probe, is that what the service manual calls a spill probe? The one that is connected to the pan, or is the lowest probe which is connected to the little board? The steam boiler is a CAS 30 (the one with the vertical water deposit).
A: Yes, the short probe mounted just above the drip pan. It is there to detect a leak and shut down to prevent flooding. I’ve had them short in the wiring or have a piece of the foil insulation ground out the probe and cause the fault light.
Q: “NO WATER ERROR” keeps popping up once out of five cycles. I checked the electrode. It still keeps popping up and tech support said to replace the electrode. I did, so this is a new electrode. Now, the tech says to replace the pump, but the pump is working.
A: If this error occurs within the first few minutes, it means that the water level sensor did not detect water within the first three minutes of beginning pump activity. This could be due to a lack of water delivery to the chamber from the reservoir or a leak (such as an incomplete door closure). It could also mean that there is an obstruction in the water delivery path, such as an occlusion at the white filter located between the reservoir and the pump or at the strainer at the rear of the unit. Another possibility might be if the solenoid located at the back of the reservoir does not open/energize during the filling process, then the unit is attempting to pump water into the chamber against a backpressure. Finally, if the unit is being “short cycled” ie: beginning a new cycle within 20 minutes of a prior cycle completion, then it is possible to overheat the water pump (due to pumping hot water from the reservoir as a result of the heating effect of the condensing coil from the prior cycle) and cause intermittent failure and/or water pump damage.
The foregoing assumes that you have the unit properly levelled, the correct water inlet time programmed and the door closing device tightened sufficiently.
If the error occurs during the heating or sterilizing part of the cycle, you have a different issue: whatever water was correctly dispensed from the reservoir into the chamber was either refluxed through a leaky solenoid back to the reservoir, the door bellows is leaking or, most commonly (especially with multiple operators), the door closing device is insufficiently tightened allowing steam to escape (subtle) and stop the pressure rise prior to reaching the set point.
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