Electronic Alarms and Home Security Devices - Ademco Vista 20P, Multi Zone HVAC and Relays

Thank you in advance to any who can help.

I have an Ademco 20P Hardwired with a 4229 Wired Expander including the relays.


I also have a Honeywell Troll-a-temp 4 zone controller for my HVAC system.

I would like to make the HVAC system more efficient by shutting down the appropriate HVAC zone when the windows/doors in a room(zone) are open.

There are commercial thermostats which do this -- but they are only available to hotel chains and are pricey.

I read in the Ademco manual under the *79 / *80 programming that you could program Zone Lists to activate the relay ?


So my questions are

1) Can 3 or 4 alarm zones be part of a Zone List, and when any of those zones fault it activates the relay on the 4229?


2) Given that windows can be left open or closed for weeks at a time (at least in my home) If a zone is faulted, and the relay on the 4229 is activated. Can that relay be active for weeks at a time without burning up ?



Any thoughts on this ?

Thanks you,

Dave B

The 20p has pretty flexible programming. You should be able to do what you are after. The relays operate at pretty low current on the activation coil. There should be no problem with the relay staying active for extended lengths of time.