Airflow Actuator problem w/ Diedrich IR-12

[reisengrindroaster]

Issue: The airflow actuator motor will intermittently fail to engage when switching from 0% to 50% airflow and also when switching from 50% to 100%. The PLC screen shows that the airflow has changed but I can tell it hasn't because 1) the exhaust temperature hasn't changed via cropster, and 2) I can open the compartment where the actuator motor is and see that the piston has not moved.

We have checked the wiring from the PLC unit to the computer/ modem inside the roaster and made sure the relay that controls the air is working. It all seems fine. Last course of action is to order a new motor from Diedrich, but without knowing that it will fix the problem, we are hesitant.

Lastly, the only pattern we have noticed is that when the actuator motor fails, if the gas level is brought to "0", we can get the motor to engage by toggling between 0 and 50% or 50% and 100%. I don't know how these two functions could be connected electronically at all.....

Has anyone else with an IR-12 experienced an airflow issue pertaining to the actuator motor failing to engage?

Thanks in advance for any light that can be shed on our problem.

 

[sae]

I suggest you call diedrich support. [email protected] or call 18772631276

 

[JohnD18]

I would say call Diedrich, too.
I do have a thought though, which came to me by you saying if you turn the gas all the way to 0, you can toggle it to get it to work...
Are all of the compartments tight, and is the vacuum sensor (the thermocouple back by the impeller is hollow and sometimes gets clogged) clear of debris? Also, make sure all the compartments are shut tight. If it senses a problem with airflow/vacuum I know the gas turns off, and I am wondering if its related to that somehow?

Just some thoughts.

 

[reisengrindroaster]

Thanks JohnD18 and sae for your input. We have checked all of those things and even did a thorough cleaning of the oxidizer this weekend including cleaning the catalyst. We thought there was a chance of some sort of back pressure issue affecting the motor if the roaster had weak airflow because of a dirty catalyst but still having the same electrical issue. Diedrich's closed vacuum system that the roaster operates on seems pretty solid and I can only deduce that this is an electronic issue somewhere between the PLC and the motor itself. I think we are at the point of ordering and new motor to the tune of $350 without really knowing if this will solve our problem.

Diedrich does not know what else to do for us....and them being in Idaho doesn't help our situation in California. Is there a known technician company that specializes in coffee roasters? I've been unable to find anything online.

Cheers!

 

[JohnD18]

Ask Diedrich in regards to the roaster tech companies. I had a problem early on when I first bought my Diedrich, and they sent out a technician in New York to help me. They should be able to give you some contacts on that.