Metasys Unt1126-0 Help!

[Boiler Guy Ray]

Help I have a metasys unt control on a rooftop unit. It is suddenly having the first stage cooling running while heating is on. When I view it through the serial port, it has a MC to the left. We switched it with a spare and it did the same thing. Any help would be great thanks
Also, are there any places that have classes on the metays
Thanks

[Cagey57]

More details please.

You said "View it through the serial port" and refered to "MC". Is there a supervisory device in the mix like an N30 ?

Is this and OEM install or by a controls or Mechanical contractor ?

Does it happen to be a York unit ?

Like to help but.... more details please.

BTW do you have HVAC-Pro software ? (aka M-Tools)

The HVAC-Pro has a pretty good help section (that could be your training). There are classes but they are pricey (from JCI).

[Boiler Guy Ray]

Thanks
Yes there is a N30 on the facility and we use HVAC pro. The rep suggested that we connect through the serial port using telnet. The rep has since gone out of business
We are controlling an older Carrier rtu. The previous service company installed the metasys The building has 7 carrier rtus each with a unt1126-0 and several zones

[The Reaper]

MC means manual command from the N-30. You will need to release the override in the N-30.

[Boiler Guy Ray]

Thanks
I will try to figure out how to do that . I appreciate it

[The Reaper]

When you are hooked up with telnet, arrow down to the point, hit F2 for command, press the spacebar until it reads release all. Select present value and default and you're all set. If that doesn't work, select override release. I'm going from memory here but this should get you where you need to be. Good luck.

[Boiler Guy Ray]

Thanks You are the man It worked

[D'Laine]

Help I have a metasys unt control on a rooftop unit. It is suddenly having the first stage cooling running while heating is on. When I view it through the serial port, it has a MC to the left. We switched it with a spare and it did the same thing. Any help would be great thanks
Also, are there any places that have classes on the metays
Thanks

If this all started suddenly, then someone may have fudged the software. You've good info to release manual over rides. You can multiple levels of overides in place, good luck.
When I used to wire these controls to operating relays, I'd always electrically interlock the controls so that heat wouldn't run if the AC was on, or vica versa.

D.