3-Way 24 Hour Timer–Damper Control
Easy to Follow Installation Instructions for the
HMI
HOYME
Adaptor TMADP-0240-3WS
A Forced Air Heating System having a Fresh Air Intake Duct leading into the return plenum
is often equipped with a
P
ower
O
pen Damper. Usually the thermostat causes the damper
to open for fresh air during furnace firing and allows the Damper to close when the fire
stops. To open the Fresh Air Damper at times when the furnace is not firing requires the
use of a 3-way switch (SPDT).
This Timer/Adaptor, however, has been designed to
override the normal operation of a fresh air damper to remain closed at certain
intervals of the day due to the reoccurrence of foul outside air.
Purchasing a 3-way switch and the necessary extras can be time consuming. By
purchasing this Ready Mounted 3-way switch with an interval timer,
TMADP-0240-3WS,
you have eliminated the trouble of buying a 3-way switch, an interval timer, an
electrical enclosure, all separately plus making the necessary connections and the
problems of assembly.
This adaptor comes completely assembled with simple, easy-to-
follow installation instructions which follow:
1. Mount the Adaptor
TMADP-0240-3WS
in a convenient place to
operate the timer on or around the furnace area with two screws
supplied.
2. Inside the adaptor are terminals
“W”, “C”
and
“R”
which are to
be connected to corresponding terminals inside your furnace. Use
3-C 18Ga. thermostat wire.
3. Connect adaptor terminals “
#2
” and
#4
to the two wires on the
motor of the Hoyme
Damper (Power Open Only).
*Automatic Setting:
When the
Adaptor
switch is in the
“Automatic”
position, the thermostat will operate normally which will cause the
damper to
open
during the heating cycle and will allow the damper to
close
when the fire stops.
*Manual Setting:
In the
“Manual”
position, the switch will override the
thermostat and will power the damper to remain in the
open
position.
*NOTE: Engaging the Timer by positioning the white pins outward overrides both the
“Automatic/Manual” settings of the 3-way switch and the thermostat to
keep the fresh air
damper closed during times of foul outside air.
See
“Interval Timer”
page 2.
This Schematic Wiring Diagram in also on the Inside Cover of the Adaptor
1015-ld Printed in Canada
