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6890 inlet cooling fan

Posted: Tue Jun 26, 2018 4:21 am
by LALman
My 6890 inlet cooling fan is not operating and swapping in a new fan was not a fix. Does anybody know if this fan is toggled in either chemstation or somewhere on the front panel?

Re: 6890 inlet cooling fan

Posted: Tue Jun 26, 2018 7:54 am
by dblux_
AFAIK it can't be toggled in front panel, nor in ChemStation.
It is "Off" when both inlet heaters are "Off" otherwise it is "On".
Have you checked new fan before mounting in GC ?
Are operating voltages same for an old and the new fan ?

BTW - tower fan can be switched on and off from the front panel.

Re: 6890 inlet cooling fan

Posted: Tue Jun 26, 2018 7:56 pm
by LALman
Its a 24V Panflo fan. I just went through and verified the fan works (with a portable 12V DC supply) and that there is nothing wrong with the cable bundle all the way to the terminating pins. Nothing looks wonky at the main board where it plugs in above the three big blue caps. Seeing 0.576 V to ground from one wire. Not enough to run a 24V fan. So, something is wrong on the main board. Maybe the best fix for now is to get a 12V or 24V DC supply for that fan.

Re: 6890 inlet cooling fan

Posted: Tue Jun 26, 2018 8:16 pm
by uzman
It is a three cable fan , two cables for power and the one for speed monitor , the supply voltage changes depending on the temperature , so you must not apply a fixed voltage on it , otherwise it gives a thermal shutdown error.

Re: 6890 inlet cooling fan

Posted: Tue Jun 26, 2018 8:24 pm
by dblux_
Yes, an independent power supply to the fan will be the cheapest solution.

Re: 6890 inlet cooling fan

Posted: Tue Jun 26, 2018 8:24 pm
by LALman
This is the fan that sits back by the split vent trap and pulls air from the front to back via the holes of the two inlets. Its a two wire fan on both my 6890 and my 6890N.

My worry is that I'm running my inlet at 280C for DRO and its hot enough that the high temp thermoplastic around the inlet is starting to melt.

Re: 6890 inlet cooling fan

Posted: Tue Jun 26, 2018 8:26 pm
by LALman
dblux_ wrote:
Yes, an independent power supply to the fan will be the cheapest solution.

OK, I'll go with that unless my tech support tells me its a specific fault that I can take action on here at my lab.

Re: 6890 inlet cooling fan

Posted: Fri Jan 11, 2019 7:35 pm
by Jackryaan
Had the same problem a year ago, Googled it up and found some tower fans on http://www.time4buying.com. I just got them and used them with my PC instead