Re: heat detector compatibility question with Radionics panel

[Nomen Nescio <nobody@xxxxxxxxx>]

gjertsen said:

>I have an old timey D8112 Radionics panel at my new house and want to
>replace the original heat detectors and smoke detectors. I don't want
>to replace the security panel at this time given that it works OK.

As others have pointed out, heat detectors are just normally open switches,
and so there are no compatibility issues.  Two-wire smokes draw power, and
create an alarm over the same wires that deliver power, hence the
compatibility concerns.  System Sensor smokes will work fine, so long as
you don't use two wire smokes with internal sounders and expect them all to
sound at once.

However, your heat and smoke detectors should not be wired directly to the
8112.   They should be wired to a D125 or D129 module, which is attached to
the side of the 8112 cabinet.  The D125 is mandatory if you are using two
wire smokes.  There is no reason you can't mix heat detectors and smokes on
the same zone, although you might want to know where the fire is.

Smoke detector reset is done from terminal 8, as I recall, and requires the
installation of an extra relay in order for the reset code, command-47, to
work.  The relay plugs into the circuit  board underneath the sheet metal
cover.

- badenov