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seascott
02-03-2010, 07:10 PM
Here's an odd one that I havent been to resolve so far. No one seems to know the answer or have ever heard of this errorwithout a corresponding mechanical failure or configuration error. It is detailed in the IOM as being exactly what it describes. My Intellipak is a SFHFC755HV77C and I have a constant Automatic reset diagnostic of "Unocc Cool Setpoint Fail""Unocc Heat Setpoint Fail" I've been doing what I consider to be a thorough job of maintaining the units and over the years have seen my share of faults where one failing component precipitates an error message for something unrelated. This does not seem to be the case here, I have been all through the programming and configuration. The units is configured the same as the other five on the roof and this is the only diagnostic that I have not been able to root out. It has survived a bcu replacement and tracer upgrades both of which required me to review the configuration thoroughly. Custom programming is minimal. It causes no problems, the unit maintains temperatures day and night but it irks me to see it year after year. Any ideas?
jayguy
02-03-2010, 08:27 PM
just so that we are all on the same page:
the diagnostic: Unoccupied Zone Cool Setpoint Failure
has a description of: The input designated as Unoccupied Zone Cooling setpoint source is out of range (Temperature < 45 F or Temperature > 94 F).
so what is your 'designated input'? gbas? you did say tracer (but you never know)
the only thing that comes to mind is wiring issues (not termination issues). check for high voltage wiring near by (even inside of the control cabinet) as well as ANY CHASES. nothing is too small or 'not likely'. why would it affect only these 2 diagnostics? who knows. but i would start with this.
seascott
02-04-2010, 06:39 PM
No GBAS here,and tracer is configured identically for every unit on the roof. I'm going to take a run through the wiring again, my strangest Intellipak problems have been partially rubbed through wiring or dying actuators sucking juice from the system and throwing up unrelated errors.
Octopus
02-04-2010, 07:31 PM
I get that when the control company holds out cool between the signal and relay. It just means the unit didn't satisfy during the unoccupied period. Energy management company involved?
seascott
02-04-2010, 07:41 PM
Nope nobody here but me. I've had the trane controls tech$ here when we upgraded the bcu but nobody had any ideas. It's not causing problems, my trends show that temperature is being maintained even when I trend the same points that Tracer is monitoring to generate this error. Ghost in the machine I suppose, it's been 8 years but im too stubborn ignore my only unresolvable diagnostic.
StayinCool
02-04-2010, 11:47 PM
Sounds to me as if Tracer has been given some unocc settings by mistake and no zone sensor is installed for reference. Also try a clear ram and reset on tracer, it could have erratica.
tipsrfine
02-05-2010, 09:59 AM
I'm guessing we're talking dc voltage so I'll go with Jayguy's advice about wiring except I'd also check every connection for tightness and/or corrosion on terminals. Had 2 similar issues in past, one was just a loose connection and the other was corroded terminals on RTU-just cleaned it with wire brush and snipped back wires to expose clean copper & no more problem.
Allen
02-05-2010, 06:40 PM
Hi Seascott,
Since the unit is saying "Unocc Heat Setpoint Failure," I would check in the Setpoint Source Selection menu. Find the "Unocc Heat Setpoint" to see what it is set to, it should be "Keypad" or "Default" because you have Summit. A setting of anything else will give you the diagnostic that you are receiving.
Good Luck,
Allen
seascott
07-06-2010, 06:21 PM
Absolutely correct, I finally got around to taking another run at this and the HI was configured to look for a sensor. I never thought to check the configuration at the panel since Tracer controls everything and the unit doesn't take over unless the BCU is down.
Healey Nut
07-06-2010, 09:15 PM
I have a solution ......... its called a 24 and "if it aint broke dont fix it"
Yes its irritating but thats what the beers for after a 24 its way less irritating and it will help you forget all about that ghostly diagnostic ........ Cheers
redfive
07-08-2010, 04:47 PM
I have a 75 ton Pack that does the same thing. It was installed in 2006. I just have gotten to were I sort of like the red light flashing. Its when its not flashing now that I get worried. I spent a hot texas summer on that inset, hot rock, no air flow roof. The only water up there, they tapped off the Larrs boiler. 160 dergrees. So with that said, if it cools who cares. I called trane on it and they said "We dont know". Good enough for me.
Redfive
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