Installation and Service Manual
Combustion Air Fans
Both the 500,000 - 750,000 Btu/hr models and the 990,000 - 2,070,000 Btu/hr models use a
and the 990,000 - 2,070,000 Btu/hr models use two fans to supply combustion air to the burners.
Fan Cleaning
Check each combustion air fan every six months. Clean the fan as required when installed in a dusty or dirty location. Oiling is not required.
Combustion Air Fan Adjustment |
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The combustion air fans are factory |
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need adjustment in most cases. Follow the steps below to |
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adjust the fan if a continuous Low Air status code occurs. | Figure 53 – Loosening Fan Transition Box Screws |
Note: On the 500,000 - 750,000 Btu/hr models the air shutter is adjusted on the side of the fan duct as depicted in Figure 52. On the 990,000 - 2,070,000 Btu/hr models the air shutter is adjusted on the rear of the fan duct as depicted in Figure 54.
1. Check for proper installation and draft in the venting system. Correct as required.
2. The following pressure settings are for installations up to 4000 feet altitude. Contact the factory for high altitude air pressure settings.
Adjusting Differential Air Pressure
The following is a recommended method for setting the differential air pressure (P) for each fan.
LESS | AIR |
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EAIR
R
O
M
Figure 54 – Adjusting Air Shutter 990,000 - 2,070,000 Btu/hr Models
Set-Up Procedure
Beside the fan duct is an air pressure switch with a large and a small tube delivering pressure from points inside the pool heater (see Figure 55). The pressure in the large tube is the chamber pressure. The pressure in the small tube is the burner pressure. They act together to make the pressure switch. By disconnecting the caps from the tees in the pressure switch hoses and connecting them to either side of a manometer, you can read the differential pressure to the switch.
AIR SHUTTER
Figure 52 – Adjusting Air Shutter 500,000 - 750,000 Btu/hr
The left pressure tapping connection on the manometer connects to the tee in the tubing from the pool heater front chamber and the right pressure tapping connection on the manometer connects to the tee in the small tubing from the burner.
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