twinning and smoke detector

[yooper]

Doing a remodel and installed a new split system. There is an existing split system twinned together (Heil). I need to install smoke detector in RA plenum in old units to bring up to code. No problem except they are not twinned together properly. I need to fix that problem before my detectors will work. I never twinned units before, but I know this was not done properly. Units do crazy things. detector is a Innovair dh100aacdclwp and want to insrall it using 24 volts.
Thanks

[qtip]

The PDF file on that detector does not show a wiring diagram but looks similar to ones I have used.
Power the detector with 24v and then with the multiple contacts provided (N.C.) wire the control voltage power supply through the detector. If the smoke detector senses smoke it will open the control circuit to the units and shut them down.

Oh yea Yooper are you from the U.P.????

[gbfromsd]

You can use a Firex brand, but an invensys has an extra set of contacts, enough for both units.

[yooper]

I don't have a problem wiring the detector, but the units aren't wired correctly together. Our main supplier is a heil dealer so I will just go there and get the proper kit. Thanks everyone.
Ya a yooper but live in TN now. I try to get back to big snow country in the summer mostly now.

[Carnak]

Add a relay.

I am guessing you have a normally closed contact on the detector.

Put the 24V of the first unit through the contact and wire the first unit accordingly. Also tap off after the duct detector contact and power the coil of a relay. Control power from the first unit powers the relay coil as long as the duct detector is not in alarm.

Wire the control voltage of the second unit through the normally open contact of this relay.