Lochinvar GAS HEATER FOR COMMERICAL POOL APPLICATIONS - Manual (Page 26)

IIN NS ST TA AL LL LA AT TIIO ON N Continued
* 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–H
Inlet Pressure
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).
Commercial Pool Heaters
26
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
TABLE-H
Outdoor Vent Cap Kits
Max. Min.
Nat. Gas 10.5" w.c. 4.5" w.c.
LP Gas 13" w.c. 8" w.c.
TABLE-I
Inlet Pressure