LOW NOx Pool Heaters, Operation, Blower Adjustment

LOW NOx POOL HEATERS

The Low NOx pool heaters are certified and tested under the ANSI Z21.56/CSA 4.7 Standard for Gas- Fired Pool Heaters.

The heater should be installed to meet all local codes, and the latest editions of the National Fuel Gas Code Z223.1 and the National Electrical Code, ANSI/NFPA 70.

OPERATION

On call for heat, the ignition system, consisting of an electronic spark module, gas valve and pilot system, is energized. Providing the pilot is proven, the blower will start running, the main gas valve will open and the heater will operate. When the operating control is sat- isfied the heater will shut down.

START-UP PROCEDURES

1.Turn on power to the heater with gas supply off.

2.Turn on gas supply.

3.Set controller to call for heat.

4.System should start as follows:

a.Spark will turn on, pilot gas valve will open, and the blower will begin running.

b.Once the blower provides pressure, the main gas valve will open.

c.Heater will operate until call for heat is satisfied.

NOTE: Door must be in place for proper operation.

BLOWER ADJUSTMENT

This Low NOx pool heater is equipped with a combus- tion air plate (baffle) mounted on the air intake to the combustion air blower. The baffle has a hole that is uti- lized to control the air inlet to the blower.

When the combustion air setting is proper, there will be some lifting of the flames on some areas of the burner deck under cold-start conditions. After about five min- utes of operation, the flames should settle down and blue tips should become visible. Lifting of flames beyond five minutes would indicate too much combus- tion air.

VISUAL INSPECTION

Flames can be observed through the slot opening above the plenum. Flame color is blue and evenly spread on the top surface of the burner. At least every three months a visual inspection should be made of the burners.

ELECTRICAL

Be sure that electrical service to the heater has prop- er overload fuse or circuit breaker protection, wire size and connections which comply with all applicable codes.

FLAME ROLL-OUT SAFETY SWITCH

Low NOx heaters are equipped with (2) thermal cut-off devices to prevent flame roll-out in the event the heat exchanger becomes blocked. One is a "manual reset" type roll-out switch that must be reset by a service technician after any over-temperature conditions have been fixed. The second is an “auto reset” type roll-out switch that resets itself after a few minutes. Excessive restriction in the heat exchanger flue passage may cause any of the two switchs to disable the heater.

Manual Reset	Auto Reset
Switch	Switch
Fig.# 9412	Fig.# 9439