Factory-Mounted Unit Options
RT-SVX26R-EN
33
4. Slide one 2” piece of the vinyl tubing provided onto the
short smoke detector inlet tube which protrudes out of
the back side of the smoke detector. Push this piece of
vinyl tubing onto the inlet tube until it contacts the end
of the plastic extension on the backside of the smoke
detector.
5. Slide the long piece of vinyl tubing provided onto one
leg of the plastic barbed elbow provided. Slide the
other end of this piece of vinyl tubing with the elbow
attached approximately 1” onto the end of the copper
sampling tube installed in the unit’s return air opening.
Position the leg of elbow without the vinyl tubing such
that it points toward the front side of the unit (directly
out of the unit toward the filter access panel).
6. Mount the smoke detector assembly into the unit.
Align the smoke detector (exhaust tube down) with the
holes in the outer panel of the barometric relief hood
and position the smoke detector flush on the panel.
Note:
On all units there is a hole with a plastic snap
bushing located on the inner vertical side of the
barometric relief hood that the long exhaust tube
must pass through. Be sure that the exhaust tube is
aligned with this hole before positioning the smoke
detector flush on the outer panel of the barometric
relief hood.
7. Secure the smoke detector to the hood with two #10-16
x 3/4’ sheet metal screws provided.
Note:
In order to perform the last part of this operation, it
will be necessary to remove the barometric relief
filter, open the barometric relief damper, and reach
inside through the barometric relief outlet to
access and connect the copper exhaust elbow to
the smoke detector exhaust tube.
8. Connect the leg of the plastic elbow without the vinyl
tubing attached that was installed in
to the
smoke detector inlet tube pushing it onto the piece of
vinyl tubing attached to the inlet tube.
9. Refer to
for wire connections of return
air smoke detector to the unit wiring harness.
10. This completes the installation of the return air smoke
detector. If the unit’s air filter(s) and/or barometric relief
filter were removed to ease installation of the smoke
detector, they need to be replaced at this time.
Airflow and Sampling
Refer to the instructions provided below regarding unit
airflow to assure that the return air smoke detector will
function properly.
Important:
The return air smoke detector is designed to
shut off the unit if smoke is sensed in the
return air stream. This function is
performed by sampling the airflow entering
the unit at the return air opening. Observe
the following instructions to assure the
airflow through the unit is sufficient for
adequate sampling. Failure to follow these
instructions will prevent the smoke detector
from performing its design function.
In order for the return air smoke detector to properly sense
smoke in the return air stream, the air velocity entering the
Figure 24.
Return air smoke detector for downflow units
SMOKE DETECTOR
COPPER TUBE
(FACTORY INSTALLED)
PLASTIC ELBOW
VINYL TUBES (7-3/4 INCHES LONG)
THREE PIECE HOOD
METAL INTAKE TUBE
METAL EXHAUST TUBE
(16.34 INCHES LONG)
VINYL TUBES (2 INCHES LONG)
TUBES INSTALL FROM BOTTOM,
TOP DOES NOT NEED TO BE
REMOVED FROM SMOKE DETECTOR
