Oil Supply Line & Filter Connections; Leak Check - Lennox OHR23-105 Installation Instructions Manual

Use continuous lengths of heavy wall copper tubing or
steel pipe for oil supply pipe. Install oil supply pipe under
floor or near walls to protect it from damage. Avoid running
pipes along joists or reverberating surfaces. Always use
flare fittings. All fittings must be accessible. Do not use
compression fittings.
IMPORTANT
Both oil supply and return pipes must be sub-
merged in oil in the supply tank.
Two−Pipe Maximum Pipe Length (H + R)
3450 RPM − 3 GPH (11.4 LPH)
Lift H" Lift H"
3/8" (10mm) OD Tubing 1/2" (12mm) OD Tubing
1−Stage 2−Stage
0' (0.0m) 84' (25.6m) 93' (28.3 m)
2' (0.6m) 73' (22.3m) 85' (25.9 m)
4' (1.2m) 63' (19.2m) 77' (23.5 m)
6 ' (1.8m) 52' (15.8m) 69' (21.0 m)
8' (2.4m) 42' (12.8m) 60' (18.3 m)
10' (3.0m) 31' (9.4m) 52' (15.9 m)
12' (3.7m) 21' (6.4m) 44' (13.4 m)
14' (4.3m) −−− 36' (11.0 m)
16' (4.9m) −−− 27' (8.2 m)
18' (5.5m) −−− −−−
Oil Supply Line & Filter Connections
One−Pipe Systems
CAUTION
Do not install the bypass plug into the pump on one−
pipe systems.
The burner is shipped with fuel pump set for one−pipe op-
eration. For one−pipe systems, the oil supply pipe is con-
nected to the inlet tap on the pump. A one−pipe system
should only be used where there is gravity oil flow to the
pump and the pipe is not run at any point above the oil level
in the tank.
1. Connect the inlet pipe to the pump inlet. Start the burn-
er.
2. Arrange the primary burner control for continuous op-
eration during purging. See figure 16.
3. Turn the bleed valve one turn counterclockwise to
open.
4. Bleed the unit until all air bubbles disappear.
NOTE − Hurried bleeding will prevent the unit from op-
erating properly.
Table 5
1−Stage 2−Stage
100' (30.5m) 100' (30.5m)
100' (30.5m) 100' (30.5m)
100' (30.5m) 100' (30.5m)
100' (30.5m) 100' (30.5m)
100' (30.5m) 100' (30.5m)
100' (30.5m) 100' (30.5m)
83' (25.3m) 100' (30.5m)
41' (12.5m) 100' (30.5m)
−−− 100' (30.5m)
−−− 76' (23.2 m)
5. Tighten the bleed valve securely.
Two−Pipe Systems
If the installation requires a two−pipe operation, install the
bypass plug included in the bag which is attached to the
pump. To convert the pump, install the bypass plug accord-
ing to the provided pump instructions. Notice in the two-
pipe system the return pipe must terminate in the tank 3"
(76 mm) to 4" (102 mm) above the supply inlet. Ensure the
return pipe terminates at the correct measurement or air
may escape into the system. This could result in loss of
prime.
NOTE− If using an outside tank in cold climates a number one
fuel or an oil treatment is strongly recommended.
1. Remove 1/4" plug from return port.
2. Insert bypass plug and tighten it. See figure 17.
3. Attach the return and inlet pipes. Start the burner. Air
bleeding is automatic.
NOTE − If a faster bleed is necessary, open the bleed
valve.
4. The return pipe must terminate 3" to 4" above the sup-
ply pipe inlet. See figure 17.
NOTE − If the return pipe does not terminate where it
should, air may enter the system, and prime may be lost.
An oil filter is required for all models. Install filter inside
the building between the tank shut-off valve and the burn-
er. Locate filter close to burner for easy maintenance.
Table 6 lists the filters for the OHR23 furnace.
Installation Clearances inches (mm)
Oil Filters
10 micron filter (no mounting bracket)
10 micron filter (mounting bracket)
10 micron replacement cartridge for filter,
45 gph
Filter restriction indicator gauge
Consult burner manufacturer's instructions packaged with
unit for further details concerning oil supply pipe connec-
tions.

Leak Check

After oil piping is completed, carefully check all piping con-
nections (factory and field) for oil leaks.
Oil Line Heater (Optional)
An oil line heater is available for the burner nozzle. When
applied to units installed in cold areas, the heater warms
the oil line for start-up.
Page 13
Table 6
Cat.
Number
81P89
53P92
53P93
53P90