Lochinvar GAS HEATER FOR COMMERICAL POOL APPLICATIONS Combustion Air Fan Adjustment for startup

Commercial Pool Heaters

INSTALLATION Continued

TABLE-H

Outdoor Vent Cap Kits

Input	Outdoor Vent Kit*
Btu/hr
500,000	ODK3075
650,000	ODK3076
750,000	ODK3076
990,000	ODK3077
1,260,000	ODK3078
1,440,000	ODK3079
1,800,000	ODK3080
2,070,000	ODK3080

* These kits include an outdoor vent cap and gasket.

Flue gas condensate can freeze on exterior walls or on the vent cap. Frozen condensate on the vent cap can result in a blocked flue condition. Some discoloration to exterior building or pool heater surfaces can be expected. Adjacent brick or masonry surfaces should be protected with a rust resistant sheet metal plate.

The Outdoor Vent Cap Kit

The optional outdoor vent cap kit is available from the pool heater manufacturer. The outdoor cap part numbers are listed by input size. See TABLE–H for kit numbers.

Install the outdoor vent cap on the rear of the pool heater, see Figure 27.

The air filter bracket will need to be rotated as shown in Figure 27 to allow proper access to the filters with the outdoor vent cap in place.

The 3-Way Valve Cover Installation

The 3-way bypass valve requires a cover for outdoor use. This cover is provided with the outdoor vent kits listed in Table-H. See page 31 for 3-way valve cover installation instructions.

Combustion Air Fan Adjustment (for startup)

For startup, the combustion air fan shutter may require adjustment. Should the combustion air fan shutter need adjusting refer to the Adjusting Differential Air Pressure instructions located under the Cleaning and Maintenance section on page 49 of this manual.

Note: The manifold gas pressure can affect the differential air pressure. Once the combustion air fan shutter has been adjusted, confirm manifold gas pressure as described in the Gas Manifold Pressure Adjustment section on page 30 of this manual.

Figure 27 – Outdoor Vent Cap Installed on Rear of Pool Heater

CONNECTING TO GAS SUPPLY

Only supply gas type specified on the pool heater’s rating plate. This pool heater is orificed for operation up to 2000 feet altitude. If installing above 2000 feet elevation, consult the pool heater manufacturer.

INLET PRESSURE: Measure inlet pressure at the inlet pressure tap located upstream of the combination gas valve(s).

See TABLE–I for maximum and minimum inlet pressures. Do not exceed the maximum. Minimum inlet pressure is for the purposes of input adjustment.

	TABLE-I
	Inlet Pressure
	Max.	Min.	TABLE–H
			Inlet Pressure
Nat. Gas	10.5" w.c.	4.5" w.c.
LP Gas	13" w.c.	8" w.c.

MANIFOLD PRESSURE: Measure manifold pressure at the pressure tap on the downstream side of the combination gas valves. The gas regulator on the pool heater’s combination gas valves is preset at the factory to supply proper manifold pressure for normal operation. See TABLE–L, page 31 for net manifold pressure settings.

If you must adjust regulator pressure, follow the instructions under Gas Manifold Pressure Adjustment, page 30. Do not increase regulator pressure beyond specified pressure setting.

Gas Pressure Test

1.Disconnect the unit from the gas supply piping system during any piping system pressure testing greater than 1/2 PSIG (3.5kPa).

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