Raypak 302A-902A manual Ignition Module, Code, Condition

36.Once the pressure switch signal is received at the ignition module the hot surface igniter is energized by a 120 VAC signal from S-1 on the ignition mod- ule. (The hot surface igniter must draw greater than 3.1 amps while being energized or ignition lockout will occur after three tries.)

37.Once the ignition module determines that the hot surface igniter amp draw is within specs and oper- ating properly, a 24 VAC signal is output from pin GV on the module.

38.24 VAC signal is received to gas valve 1 thus ener- gizing it.

39.The stage 1 LED on the diagnostics display board is now illuminated.

40.The coil of relay K-2 (N.O.) is now energized with the (K-2) contacts closing downstream of the stage 2 connections.

41.The gas coming through the burners should ignite from the heat of the hot surface igniter and the flame should carry over from one burner to the other burners of stage 1. The remote sensor is now trying to sense the flame. If the flame is not sensed within 4 seconds, the ignition module will shut down the gas valve and retry the hot surface igniter. During ignition retry the heater must per- form a 15-second pre-purge and an approximate- ly 30-second igniter warm-up before opening gas valve 1 again. The standard ignition module will attempt ignition a maximum of three times prior to ignition lockout.

42.(Models 302A-402A only) 24 VAC is now waiting at pin 3 of the stage 2 connection on the CPW board.

43.(Models 502A-902A only) After gas valve 1 opens and flame rectification is received, time delay relay 1 (TD-1) starts a 5-second countdown.

44.(Models 502A-902A only) After the 5 second countdown from TD-1, 24 VAC is waiting at pin 3 of the stage 2 connection on the CPW board.

45.After closure of the stage 2 contacts Gas valve 2 in energized.

46.The stage 2 LED on the diagnostics display board is now illuminated.

47.The heater is now operating at full fire.

Ignition Module

When additional heat is needed, the combustion air blower starts to purge air from the combustion cham- ber for about 15 seconds. On proof-of-air flow, the air-

Fig. 29: Ignition Module

proving switch closes and the igniter is energized. To ensure safe operation, the gas valve cannot open until the igniter is verified. The main burner is automatically lit when the device is powered and pre-purged. The heater performs its own safety check and opens the main valve only after the igniter is proven to be capa- ble of ignition.

The standard ignition module will attempt to light three times before locking out. To reset it, turn off power to the heater, wait 30 seconds and re-apply power.

Code	Condition
On	System OK;
	No faults present
Off	Possible control fault;
	Check power
1 Flash	Low air pressure, brief flash-
	ing normal on start-up
2 Flashes	Flame in combustion
	chamber; No call for heat
3 Flashes	Ignition lockout
4 Flashes	Low igniter current
5 Flashes	Low 24VAC, check control
	supply voltage
6 Flashes	Internal fault;
	Replace control

Table O: Ignition Module

Diagnostic LED Codes

36