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Finnigan GCQ GC question

Discussions about GC and other "gas phase" separation techniques.

6 posts Page 1 of 1
Hello,

i have a Finnigan GCQ and i have a "OVER TEMPERATURE" problem. Is very possible the company i bought it from wired it wrong inside, since i already corrected a problem with the heater. They connected it for 230V when the oven is on 110V. This made me think they connected wrong the fan also.

If you are an Finnigan GCQ owner, please be so kind and answer me these:

1. Is the heated air exhausted on the top hole or the bottom one ? You can easily check this by setting 100 degrees, then 50 degrees and while it is going from 100 to 50, put your hand behind and check if is the top one or the bottom one. There is no risk on burning at this temperature.

2. Is the fan rotating clockwise or anticlockwise ? You can easily check this by opening the door and watch the fan while it stops.

I will love a service manual, but it was impossible for me to find one. Actually i detected the wrong installed heating resistor with a Trace GC 2000 service manual. They are alike, but in this case, is impossible to figure out the jumpers.

So if it happens to have a service manual i will love to have it.

Thank you in advance,
Vlad Popovici
Hello,

if no one has a Service Manual for Finnigan GCQ, please anyone can make me some pictures of the PCB in the power area ?

I need to see how the fan is connected and configured, also how the heating part of the injector is connected. I need that from a 115V Finnigan GCQ GC, the oven not the MS detector.

Thank you a lot,
Vlad Popovici
I can possibly help you with this. Altho i dont know too much about what im talkin about... I am unable to take a photo or look at fan direction until tuesday. Have you measured the element resistance? I think the 110v is around 10ohm and the 230v is around 40ohm, but I can check next week for you. The main variation on the board for voltage change is the large jumper with looped wires all are white except one which is black. For 110v operation the black lead should be close to the PCB transformer. This big jumper modifies transformer taps and fan wiring. Additionally all the heating elements, including injector ports any FID etc need to be looked at, they should have voltage written on them, if you need 110v elements I could help you out. Also, the black cooling fan mounted to back panel must be checked for voltage.

Additionally look at J3 the jumper should be across pins 1 and 2 for 110v.
Also, take a photo of yr current GCQ voltage selection board.
Hello,

thank you for your help. Someone sent me some pictures and i was able to set it up correctly. But your words confirmed me i did good.

It was set for 230V so i had to change the voltage jumper jumper, the bended wires ruler (JP3) and set the heating element resistor as for 110V.

However after doing this i still had the overheating problem. I came to discover that the cooling fan in the back was malfunctioning. After 10-15 min that fan will stop and never start again unless you power off the system and let it that way 30 mins. I ordered a new one but meanwhile I opened that fan cleaned it and lubricated it. Also I noticed inside the fan a sensor for overheating, and that was guilty for stopping the fan after 10 mins.

All is working now.

I still wonder about the rotation direction of the inside fan, and if the top air vent is right one to exhaust the heat. If you can check that, would be awesome.

Thank you again,
Vlad Popovici
seen from the inside of the oven the fan of my thermo finnigan trace GC (and trace GC ultra) turns counter clockwise

regarding your exhaust-question, I don't think I'm able to help since at my GC's the fresh air intake seems to bee in between the exhaust (fitted with a chimney).
6 posts Page 1 of 1

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