Lochinvar 502 - 2072, 402 - 2072 service manual Checking combustion air pressure

Copper-fin II/IIE Boiler, Water Heater and Pool Service Manual

2 Maintenance (continued)

Access to the burner will require the following steps:

1.Turn off main electrical power to the appliance.

2.Turn off main manual gas shutoff to the appliance.

3.Remove the lower outer front access door.

4.Disconnect the manifold(s) from the gas train using the union(s) just below each gas valve.

5.Disconnect the wiring to the hot surface igniter(s) and ground.

6.Disconnect burner pressure line at burner.

7.Remove the screws from the manifold mounting bracket(s) and remove the manifold(s).

8.Remove the screws from the burner mounting flanges and slide the burner(s) out toward the front of the unit. Use caution to prevent damage to the burners, refractory, hot surface igniter, and wiring.

9.Remove soot from the burners with a stiff bristle brush. Dirt may be removed from the burner ports by rinsing the burner thoroughly with water. Drain and dry burners before re-installing. Damaged burners must be replaced.

10.Reassemble in reverse order.

NOTICE	When installed in a dusty and dirty location,
	the burners may require cleaning on a 3 to 6
	month schedule or as needed, based on the
	severity of contamination. Contaminants
	can be drawn in with the combustion air.
	Non-combustible particulate matter such as
	dust, dirt, concrete dust, or drywall dust can
	bloc burner ports and cause non-warrantable
	failure. The standard inlet air filter will help
	eliminate dust and dirt from entering the
	unit.

Checking combustion air pressure

The combustion air fans are factory pre-set and should not require adjustment in most cases. Follow the steps in the Checking / Adjusting Combustion Air Pressure Section to adjust the fan if a continuous Low Air status code occurs.

NOTICE	On the 399,999 - 750,000 Btu/hr models,
	the air shutter is adjusted to the side of the
	fan as depicted in FIG. 2-2. On the 990,000
	- 2,070,000 Btu/hr models, the air shutter is
	adjusted by sliding the arm located on the
	front of the air box as depicted in FIG. 2-3.

Check for proper installation and draft in the venting system prior to any adjustments. Correct as needed.

Figure 2-2_Adjusting air shutter - 399,999 - 750,000 Btu/ hr Models

LESS AIR

MORE AIR

AIR SHUTTER

Figure 2-3_Adjusting air shutter - 990,000 - 2,070,000 Btu/hr Models

NOTICE

While burners are removed, check the heat exchanger surface for sooting. If present, the heat exchanger must be cleaned. Reference the Heat Exchanger Cleaning procedures in this manual.

MORE AIR

LESS AIR

AIR SHUTTER

ADJUSTING BRACKET

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