Lochinvar 000, 1 H. Lubrication, I. Combustion And Ventilation Air, J. Control Circuit Voltage

9.Carefully reinstall the heat exchanger if removed from the appliance.

10.Reinstall inner rear jacket panels, bypass piping

and condensate hoses. Use new gasket material to ensure a proper air seal.

11.Reassemble all water piping. Test for leaks.

12.Reassemble rear outer jacket panels.

13.Cycle unit and check for proper operation.

H. LUBRICATION

Combustion Air Blower: Each combustion air blower should be checked every 6 months. Clean internal filter to blower as required when installed in a dust or dirt contaminated location. See Combustion Air Blower in the component section for cleaning procedure. The motor and bearings on the combustion air blower are sealed and permanently lubricated requiring no addition of oil or lubricants.

Water Circulating Pump: Inspect pump every 6 months and oil as necessary. Use SAE 30 non-detergent oil or lubricant specified by pump manufacturer.

I. COMBUSTION AND VENTILATION AIR

Check frequently to be sure the flow of combustion and ventilation air to the boiler is not obstructed. Combustion and ventilation air must be provided to the mechanical room with openings sized per the requirements of the National Fuel Gas Code when the appliance is installed with a standard Category IV vent system. The optional Direct-Vent and Intelli-Vent systems use a separate combustion air pipe to bring in combustion air from the outdoors directly to the appliance. Ensure that the construction air filter is NOT used for continuous service after the construction phase.

J. CONTROL CIRCUIT VOLTAGE

This appliance uses a transformer to supply a low voltage control circuit. The voltage on the secondary side should be 24 to 28 VAC when measured with a voltmeter. A secondary voltage of 18 VAC or less supplied to 24 VAC components may cause operational problems. A 5 AMP circuit breaker is provided on the secondary side of the transformer. The circuit breaker is located on the left front control panel. A tripped circuit breaker indicates a short in the 24 VAC controls that must be corrected.

			ORIFICE
		GAS		BLOWER
			AIR BOX
			(FRONT VIEW)
			GAS
				AIR
				GAS
	GAS			3.5" W.C. = Pair
GAS	AIR	AIR
GAS VALVE				BURNER
(TOP VIEW)
				MANIFOLD AIR PRESSURE
		– – – – = FIELD CONNECTED

FIG. 79 Measuring Combustion Air Pressure Differential to Ratio Gas Valve

K. COMBUSTION AIR MEASUREMENT

This appliance uses a variable speed combustion air blower to operate the combustion process and venting system. A single combustion air blower is used to supply combustion air to the burner. The discharge air from the blower is factory pre-set and is not field adjustable. The blower and transition are mounted on the top of the burner. The blower is enclosed inside of the top chamber.

There is a pressure test tree located in the top chamber of the appliance. This pressure test point tree can be accessed by swinging out the front control panel. The pressure test tree is mounted on the front edge of the combustion air blower. It consists of an angle support and four labeled test cocks. There is one cock for + air and one for - air, one cock for + gas and one for - gas. Differential air pressure measurement at the combustion air blower will utilize both the + air and - air test points.

1.Open the front control panel and swing the controls out. Locate the pressure test tree on the front edge of the combustion air blower. The + and - air pressure terminals will be used to check differential air pressure from the blower discharge to the burner inlet. Each air pressure connection point will have a small manual cock to attach a hose.

2.Connect a hose from the + air and the - air to each of the two sides of a manometer. This will allow the two pressure points to be measured at the same time. Open the two air pressure test point cocks.

3.Set the Command Display to a set point which will fire the burner at 100% of rated input.

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