Fan/Limit Control - Rheem OBF Series Installation Instructions Manual

TABLE 8
DELAVAN
MODEL
NOZZLE
NUMBER
SIZES
-067 —
-0112 (1.0) -70°B
-150 (1.2, 1.35) -70°B
*Recommended temperature rise is the midpoint of the given range.
TRUE-SPOT
True-Spot smoke tester (see figure 23)
by Bacharach is used to check smoke
levels in flue products.
FIGURE 23
TRUE-SPOT
INSTRUCTIONS FOR USE:
1. Tear a sample strip of filter paper
along the perforation line; loosen
the clamp screw, insert the filter
paper strip in the slot and tighten
the clamp screw.
2. Insert the sampling tube into the
flue through a 1/4" diameter hole
between the draft regulator and
the furnace flue outlet (see
figure 24).
FIGURE 24
SMOKE SAMPLE
DEL-O-FLO TEMPERATURE RISE
NOZZLE RANGE*
SIZES (DEGREES F)
(.50, .65) -70°B 40 - 70
(.75, .85) -70°B 50 - 60
— 60 - 90
3. Pull the True Spot handle through
10 full pump strokes.
4. Remove the filter paper strip from
slot (see figure 25).
FIGURE 25
SMOKE SPOT
5. Match the smoke spot on the filter
paper to the closest color shade on
the Bacharach oil burner smoke
scale RR 776 (see figure 26).
FIGURE 26
SMOKE SCALE
6. To take additional samples clamp
the filter paper strip in the slot so
that the previous spot is visible.
SMOKE SCALE READINGS:
1. Excellent - Little, if any, sooting.
2. Good - May be slight sooting, with
little, if any, increase in flue gas
temperature.
3. Fair - Substantial sooting, but
rarely will require cleaning more
than once a year.
4. Poor - This is a borderline smoke
- some units may soot only moder-
ately, others may soot rapidly.
5 Very Poor - Heavy sooting in all
cases - may require cleaning
several times during a heating
season.
6 Extremely Poor - Severe and
rapid sooting - may result in dam-
age to the stack control and
reduce the overfire draft
dangerously.
TIPS FOR BETTER SMOKE
READINGS
1. Before using, tap the sampling
tube to loosen any soot or rust,
tighten the clamp screw without
any filter paper in the slot and
purge with several rapid pump
strokes of room air.
2. Warm the True-Spot to room
temperature before using.
3. In sampling, be sure to pull the
pump handle through 10 full
strokes and hold for several
seconds at the end of each pull
stroke. Use a steady pull motion
such that a full stroke is obtained
in 3 or 4 seconds.
4. Hold the smoke scale with the
filter paper at arm's length when
comparing the spot with the chart.
5. Take several readings.
6. Keep the Smoke Scale clean and
store in an envelope provided
when not in use.

FAN/LIMIT CONTROL

The high limit cut-off switch is factory
set to meet safety requirements. This
setting is not adjustable.
The fan is cycled by a solid state fan
timer control located in the blower
cavity (see figure 14).
19