Reznor ADFH Unit Installation Manual - Manual (Page 25)

Form I-ADF, P/N 131805 R5, Page 25
If the slope gauge reading is greater than -.25" (such as -.10"
w.c.), adjust the drive to increase the blower speed.
(1) Turn disconnect switch OFF.
(2) For systems with smaller than 7-1/2 HP motor
(a) Loosen belt tension and remove belt.
(b) Loosen the set screw on the side of the pulley away from
the motor.
(c) Turn adjustable half of the pulley inward to increase
blower speed. One turn of the pulley will change speed 8
to 10%.
(d) Tighten the set screw on the flat portion of the pulley
shaft.
For systems with 7-1/2 HP and larger motor
(a) Slack off all belt tension by moving the motor toward
driven shaft until the belts are free of grooves. For easiest
adjustment, remove the belts from the grooves.
(b) On the outer locking ring, locate the two locking screws
that are directly across from each other. Loosen, but do
not remove, those two screws. Do not loosen any other
screws.
(c) Adjust sheave to desired pitch diameter by turning the
outer locking ring. One complete turn of the outer lock-
ing ring will result in .233" change in pitch diameter. To
increase blower speed, decrease diameter.
CAUTION: Do not adjust sheaves in either direction to
the point where moveable and stationary flanges are in
contact.
(d) Re-tighten the locking screws.
All Motor Sizes - Replace the belts and check belt tension. Be
sure that belts are aligned in the pulley grooves and are not
angled from pulley to pulley.
If the slope gauge reading is less than -.75" (such as -1.0"
w.c.), adjust the drive to decrease the blower speed.
(1) Turn disconnect switch OFF.
(2) For systems with smaller than 7-1/2 HP motor
(a) Loosen belt tension and remove the belt.
(b) Loosen the set screw on the side of the pulley away from
the motor.
(c) Turn the adjustable half of the pulley outward to
decrease blower speed. One turn of the pulley will
change speed 8% to 10%.
(d) Tighten the set screw on the flat portion of the pulley
shaft.
For systems with 7-1/2 HP and larger motor
(a) Slack off all belt tension by moving the motor toward
driven shaft until the belts are free of grooves. For easiest
adjustment, remove the belts from the grooves.
(b) On the outer locking ring, locate the two locking screws
that are directly across from each other. Loosen, but do
not remove, those two screws. Do not loosen any other
screws.
(c) Adjust sheave to desired pitch diameter by turning the
outer locking ring. One complete turn of the outer lock-
ing ring will result in .233" change in pitch diameter. To
decrease blower speed, increase diameter.
CAUTION: Do not adjust sheaves in either direction to
the point where moveable and stationary flanges are in
contact.
(d) Re-tighten the locking screws.
All Motor Sizes - Replace the belts and check belt tension. Be
sure that belts are aligned in the pulley grooves and are not
angled from pulley to pulley.
 (C) Turn ON the disconnect switch and re-check the slope gauge. If air pressure differential is within the limits of
.25" to .75" w.c., no further adjustment is required. If the air pressure differential is not within the limits, re-adjust the
blower speed.
 (D) When the differential air pressure is within the limits, check the motor amp draw with an ammeter to be sure that
the motor is not overloaded. Amps are shown on the motor nameplate.
 (E) If an inlet or outlet duct system is attached to the heater, run the blower to purge the volume of air from the duct
system with at least four air changes.
 (F) If the system includes an optional dirty filter light, while the blower continues to operate, set the switch so that
the indicator light (on the remote console) will activate at approximately 50% filter blockage. Calibrate the switch to
this measurement by turning the set screw on the switch clockwise until the filter light is energized or the screw is
bottomed out. At that point, adjust the set screw three full turns counterclockwise or until the screw is top ended. At
this setting the contacts will close causing the light to signal that the filters require cleaning at approximately 50%
blockage.
 (G) Turn the disconnect switch OFF. Disconnect the manometer and the slope gauge. Replace caps removed to
connect the slope gauge and the plug in the gas pressure tap.
5. Check pilot and burner ignition --

Turn the disconnect switch ON. (Lights as explained in Startup Steps 2 and 3 should be energized). Put the burner
switch (on the electronic circuit board) in TEST position. After 15-20 seconds, the "Pilot Valve" light will light to
signal the pilot ignition, followed by the "Main Valve" light signaling main burner operation. All lights should be lit
except "System Switch" (12 lights total).
 With both the burner and blower operating, measure the gas pressure at the burner. Gas pressure should match
the required manifold pressure listed on the rating plate. (If pressure does not match the required pressure, further
testing is required in Step 7.) Remove the manometer.
 Leak test all connections in the pilot and main burner supply lines. WARNING: DO NOT TEST WITH OPEN
FLAME.
 Turn OFF the manual gas valve. Wait 30 seconds for unit to cool. Return both burner and blower switch to OFF
position. Turn OFF disconnect switch.