Berner International B-22, B-24 Maintenance, XI. Troubleshooting, Burner Adjustment See Operation

(F)Fan Starter: Although not normally considered a safety device, the fan starter is wired so that its 13-14 interlock powers the control system. Thus the main fan must be energized before the gas system can be pow- ered. This provides one more assurance, in addition to the Airflow Switch, that the fan is operating before heat comes on.

(G)Secondary Safety** and Bleed Valves (or “Block & Vent Valves): A second main line gas valve is installed downstream of the primary safety valve. A vent line with an electrically operated normally-open valve takes off lat- erally between the two main line valves. This vent line must be piped to atmosphere outside the building, by the customer on installation (See Suggestions for Regulator.)

IX. O P E R ATION

G A S		MODEL B-22, 6500 CFM
SUPPLY
	1000’S		RISE	FINAL TEMP.
PRESSURE
(in.w.g.)	BTU/HR		(ºF)	(ºF)*
5”	700		99	169
6”	765		109	179
7”	820		117	187
8”		7” MAX. RECOMMENDED
G A S		MODEL B-24, 7900 CFM
SUPPLY
	1000’S		RISE	FINAL TEMP.
PRESSURE
(in.w.g.)	BTU/HR		(ºF)	(ºF)*
5”	790		92	162
6”	865		101	171
7”	930		109	179
8”	990		116	186

*Based on 70º F. inlet temperature.

(A)Gas Adjustment: Heat output is adjusted by varying the outlet pressure of the regulator (see Gas Pressure Regulator). A pressure gage may be attached to the pip- ing at a leak-test connection. Table 1 shows performance at various inlet pressures.

(B)Pilot Adjustment: This heater is equipped with inter- ruptedpilot;i.e.,aftermainburnerignites,pilotiscutoff. Scanner then senses main flame only. Pilot flame was properly adjusted at the factory.Field adjustment is pos- sible by removing the protective cap and using a screw- driver with a small bit.

X.MAINTENANCE

(Note: See wiring diagram for part number and manufacturer of any control component. See manufacturer’s instruction sheets for more information.)

(A)Fan Motor Bearings: Refer to green sheet on mainte- nance of direct-connected fans. Most fan motors have a 1/8" NPT pipe at each bearing, which may be removed for lubrication, in the event lube tubes were not factory- installed.

(B)Burner: Side plates and their air holes should be checked periodically, to be sure these parts are not fouled or plugged.

(C)Burner Adjustment: (See Operation).

(D)Fireye: The UVM-IF utilizes solid state components. The only required maintenance is on its external compo- nents; i.e., the Flame Rod and the Ultra -Violet Scanner. See “Maintenance” in manufacturer’s bulletin C-400.

(E)Scanner: Remove scanner occasionally,cleanlens, and be sure that mounting pipe nipple is clear of insects and dirt.

(F)Spark Ignitor: Ignition takes place by means of a spark jumping from the ignitor to the side plate of the burner. The spark gap should be 1/8" to 3/16" (. 12" -. 19"), and located downstream of an air mixing hole, so that there is a gas-air mixture to be ignited. Check for carbon “bridge” between electrode and burner which may short out spark and prevent ignition.

XI. TROUBLESHOOTING

First check for loose wiring connections.

Then check the following for specific symptom:

(A)Fan Won’t Start -

(1)Selector in “OFF” position.

(2)Check 3-phase line leads for power across all 3 phases, if one line is dead, check fuses or breaker in main disconnect.

(3)Check fuse on control circuit transformer.

(4)Try “SUM” setting. If fan runs, but won’t run on “@”, check 1T’HS outdoor thermostat (if used) for open R-B contact; check limit switch on door for open-contact.

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