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lilquiz
01-15-2005, 05:24 AM
working on a HONEYWELL W7751E vav controller. looks like i inhertied this from another company who had knowledge problems as well (blind leading the blind) any-hoo... i arrived to find a regular clicks-on t-stat instead of the t-stat specified. ordered and installed a T7750C. the controller is giving a fast blink, which indicates alam for some thing. checked mall store next door it is also giving alam but is working .the system after a long time delay shut damper and energized heat stips .i tried to recycle unit, but damper did not open to cool when t-stat was turned down...nor did it energize heat again, when damper was already closed... how and what do i need to for diagnsis...do i need to access and re-program the controller... and what computer link or program is needed? would really appreciate any help you could muster on this. THANKS

sysint
01-15-2005, 07:47 AM
Question 1: Is there wire connected to the LON?

If YES, then find out what software is running the system. Follow the comm. It may lead to an SLTA and a modem but find out.

If NO, and this is a standalone box then you probably should get any LNS based software or a Honeywell program like LONspec. Circon NI or VI, Lonmaker, Lonwatcher, etc...

Plugins are available on the web for this device. (Free)

ross
01-15-2005, 07:48 AM
You will need the honeywell program Care I think, You did say this was in a mall right? It has been some time that I did mall work but most of the time I noticed that if a system like that is in a store the frontend is controled by the mall they tell the box what to do. This would be overkill for a stand alone unit. Go to maintance they should be able to pull up the box. Good luck

sysint
01-15-2005, 08:42 AM
Not necessarily CARE. It would be E-vision which is now rolled into the latest CARE. If it's standalone, (even if it's not) you can use any of the programs previously stated. They all work.

Anyway, it's entirely possible that this is standalone floating.... These controllers are relatively cheap-(inexpensive)

The old stat, where exactly on the controller was it hooked up to?

lilquiz
01-15-2005, 09:21 AM
old stat was disconnected but was not the right type...where would i aquire software and comunication linkage...web based if possible..or form # 74-2968 apendix c

sysint
01-15-2005, 11:03 AM
I understand what you are saying about the old thermostat. Which terminals was it hooked up to?

Again, it will be problematic if this is hooked up to a commm to just slap on a server and go....

lilquiz
01-15-2005, 08:16 PM
it was not hooked up at the controller but three of the wires were stripped like it had been

marvintm
01-25-2005, 09:25 PM
The fast blink can occur
1) If the controller has an alarm like room freeze alarm or low airflow (all controls being functional)
2) If the controller is not seeing a sensor it was programmed for (ie wall sensor)
3) Any number of communication faults including missing sending or recieving bindings from other controllers, or front end.
4) There was an old "issue" or "feature" from controllers date coded somewhere in the 2000 - 2002 era (i think) where a component marked C58 (a SMD capacitor), shorts and causes the controller to do funny things including the fast blink. If you disasseble it far enough, you can find and cut (or crush) it off of the board leaving an open circuit behind and it will be fixed forever. This was an actual repair method listed by Honeywell.
5) Someone "decommissioned" the controller completely. Get programming tools, and start over.

Either way, you MUST have the database and software used originally on the job if boxes are networked together. You pretty much cannot upload an existing controller without the original database. If you ignore this warning, you will have two controller number "1"'s onsite and all heck breaks loose on the rest of the bus.

sysint
01-26-2005, 07:31 AM
I was waiting to see if that conventional stat was simply going to a DI and utilizing a low temp to activate nviManOcc.

Anyway, yes you will have a problem with not having the database. Although, I have run H-well in contiguous database with Circon with no problems in the past.