Trane Voyager RT-SVX17C-EN, Установка, эксплуатация и обслуживание

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Service & Maintenance
Fan Belt Adjustment
The Supply Fan belts must be inspected periodically to as-
sure proper unit operation.
Replacement is necessary if the belts appear frayed or worn.
Units with dual belts require a matched set of belts to ensure
equal belt length. When installing new belts, do not stretch
them over the sheaves; instead, loosen the adjustable mo-
tor-mounting base.
Once the new belts are installed, adjust the belt tension us-
ing a Browning or Gates tension gauge (or equivalent) illus-
trated in Figure 16.
1. To determine the appropriate belt deflection:
a. Measure the center-to-center distance, in inches,
between the fan sheave and the motor sheave.
b. Divide the distance measured in Step 1a by
64; the resulting value represents the amount of
belt deflection for the proper belt tension.
2. Set the large O-ring on the belt tension gauge
at the deflection value determined in Step 1b.
3. Set the small O-ring at zero on the force scale
of the gauge.
4. Place the large end of the gauge on the belt at the cen-
ter of the belt span. Depress the gauge plunger until the
large O-ring is even with the of the second belt or even
with a straightedge placed across the sheaves.
5. Remove the tension gauge from the belt. Notice that the
small O-ring now indicates a value other than zero on the
force scale. This value represents the force (in pounds)
required to deflect the belt(s) the proper distance when
properly adjusted.
6. Compare the force scale reading in step 5 with the appro-
priate “force” value in Figure 17. If the force reading is
outside of the listed range for the type of belts used, ei-
ther readjust the belt tension or contact a qualified ser-
vice representative.
Figure 16
Typical Belt Tension Gauge
Note: The actual belt deflection force must not
exceed the maximum value shown in Figure 17.
7. Recheck the new belt's tension at least twice during the
first 2 to 3 days of operation. Readjust the belt tension as
necessary to correct for any stretching that may have oc-
curred. Until the new belts are “run in”, the belt tension will
decrease rapidly as they stretch.
See Supply Fan Sheave and Belt Table on the
following page.
Electric Heat Sequence Of Operation
When heat is required and the Fan selection switch is in the
“AUTO” position for constant volume applications, (fan runs
continuously on variable air volume applications), the
RTRM energizes the Fan coil approximately one second
before energizing the first stage electric heat contactor (AH).
A 10 second minimum "off" time delay must elapse before
the first stage heater is activated. When the heating cycle is
completed, the RTRM de-energizes the Fan and the heater
contactor (AH) at the same time.
The RTRM cycles the first stage of heat as required to main-
tain zone temperature or discharge air temperature, which-
ever is applicable. If the first stage cannot satisfy the heating
requirement, the RTRM energizes the second stage electric
heat contactors (BH) and (CH) providing first stage has
been on for at least 10 seconds or the second stage has
been off for at least 10 seconds. (CH contactor is used on
54KW and larger heaters.)
The RTRM cycles the second stage electric heat as re-
quired to maintain the zone temperature or the discharge
air temperature, whichever is applicable.