Tane Absorption Chiller "Starter did not transition"

[sdmtl]

There are two Absorption Chillers manufactured by Trane Company, the model is ABSC-075 (abs-m-4_02231994.pdf) with 750 Nominal Tonnage each. The two units are operated by us for 12 years.
The Chillers have been utilized for the annual cycle at the beginning of this summer. After the automatic start, we realized that one of these units is not working properly. The problem is that when the improper one starts and passes the prestart steps, this is the time for the Pump to activate but in this step, after 3-5 seconds (just before the display indicates – Unit is Running: SOFTLOADING) the unit get shut down.
During this time a message is shown in the operator interface of the unit and in the diagnostic section which is “Starter did not transition”, since the message is not mentioned in the Operation Manual at all.
According to the mentioned message, there are some important points which come into our mind and are listed below:
- We would know from the Auxiliary Water Valve that one of the pump seals is malfunctioned.
- Since the working time of the unit is above 15000 hours, the pump should be serviced and we are sure that we will do so, but since, during these three seconds the current draw of the solution pump motor (1T1, 1T2, and 1T3) does not exceed 16 Amps. Therefore the pump is working in a proper way, and there is not any possibility for a problem in solution pump except the seal failure.
Thus, is it possible that the message does not relate to the Pump failure and relate to the starter module of the unit?
It is worth to mention that since the Trane Company does not have any representative in Iran, we are not able to use the maintenance services here.

Thanks in advance for your consideration,
Best regard,
Saeed Babaei
Executive director of Takro Iran Company

(takroiranco@gmail.com)

[goshen]

Hi what type of controller do you have on the unit?
if it is a ucp2 then check for the corect configuration.
any way this fault is usualy generated when the controller doesnt get a closed contact from the starter contactor which would mean check all your contacts !!

[BekTek]

There will be a pair of wires from starter that feedback to the UCP.
Some of the Cutler Hammer contactors needed to have the auxiliary switch shimmed a bit to make better contact.
Like the previous poster had said the configuration might need to be checked but I don't remember seen a Trane absorber with a Wye Delta starter on it due to the low amp draw on the motor(s) so you shouldn't have a transition failure.
Check the wiring diagram to see where the aux contact feed to/from and check if there is anything in between.