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[sesheely]

I am integrating into the VT7200 BACnet thermostat.  I have one on a network in our office, just trying to get a feel for it, modifying programming etc.  I have the sequence of operation set to heating only (2 - MV:39), I can set the limit of the heating setpoint (AV:27), but when I try to set the cooling limit (AV:28), it will not allow a limit.  It will adjust on the VT7200 all the way down to 40degF.  I know it is a heating only mode, but shouldnt the limit still work?

Thanks in advance!

[Zinc22]

Nope 

The limit are designed to limit energy usage.

Not to prevent shutting down the equip.

The High heat limit will prevent the heating setpoint only from being raised above X
The Low cool limit will prevent the cooling setpoint only from being lowered below Y

Remember that these devices have 4 independent setpoints.

In the case of your application, only the heating setpoints are used, thus only heating limit has effect.

The stat will prevent users to hit 90F for a heating call, but wil let them freeze out if they wich to lower it to 50F.

You may also totally lock out user adjustments by using the lockout parameter or make any user local setpoint changes be temporary ( they revert to the network values after TOccTime expire ) by setting your setpoints to Temporary. Then any adjustments made by the user are non permenent ones.

Michel