Heater Sequence of Operation, Ignition Module

Heater Sequence of Operation

If all limits are satisfied and there is a call for heat:

1.The heater pump is powered and begins circulat- ing water through the heat exchanger.

2.The blower is powered and goes through a 15 sec- ond prepurge beginning when air flow is proven by closure of the blower suction air pressure switch.

3.The igniter is powered, and once proven, heats up for 20 seconds.

4.The gas valve is then energized for a 4 second trial for ignition period. Trial for ignition is fixed at 50% input. The heater is allowed to modulate once flame is proven and the firing rate will adjust to match the load based on the configuration and set- tings of the temperature control or external input.

5.Once the heat demand is satisfied the gas valve will close and the blower will run a 30 second post purge. The heater pump will continue to circulate water for 0 to 10 minutes depending on the pump delay setting on the Raypak modulating tempera- ture control.

Ignition Module

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

Fig. 37: Ignition Module

The optional single-try ignition module will lock out after failing to light one time. To reset it, press and release the small, recessed black push button located inside of the cut-out on the lower right-hand corner of the ignition module case. Turning off the power to the heater WILL NOT reset the ignition module.

	Code	Condition

	On	System OK; No faults present

	Off	Possible control fault; Check power

	1 Flash	Low air

	2 Flashes	Flame in combustion chamber;
	2 Flashes	No call for heat
		No call for heat

	3 Flashes	Ignition lockout

	4 Flashes	Low HSI current

	5 Flashes	Low 24 VAC

	6 Flashes	Internal fault; Replace control

Table S: Ignition Module Diagnostic LED Flash Codes

High Limit—Manual Reset

This heater is equipped with a fixed setting manual re- set high limit temperature device as standard or it may have an optional adjustable setting manual reset high temperature device.

The fixed setting manual reset high limit is located on the In/Out header of the heat exchanger on the right side of the heater (accessible through the front door for reset as necessary).

The optional adjustable manual reset high limit is lo- cated inside the heater junction box. Push the reset button and adjust the setting to approx. 40°F (20°C) above desired outlet temperature.

503-2003 specifications

The Raypak 503-2003 is a notable entry in the world of water heating solutions, renowned for its efficiency and reliability in both residential and commercial settings. This model is designed to provide exceptional performance while maintaining ease of use and minimization of environmental impact.

One of the standout features of the Raypak 503-2003 is its advanced heating technology. The unit utilizes a durable, copper heat exchanger which ensures quick and efficient heating of water. This heat exchanger is known for its ability to transfer heat effectively, leading to reduced energy consumption and lower utility bills. The design also allows for a seamless operation, ensuring that the system heats water swiftly without sacrificing performance.

In addition to its efficient heating capabilities, the Raypak 503-2003 is equipped with innovative controls. The digital control panel allows users to easily set and adjust the desired water temperature. This feature provides a level of convenience that simplifies operation while enhancing user experience. Furthermore, the smart technology employed in the unit ensures that it operates within optimal parameters, avoiding unnecessary energy expenditure.

Durability is another hallmark of the Raypak 503-2003. Built with heavy-duty components, this water heating solution is designed to withstand the rigors of continuous use. The rugged construction ensures longevity, making it a cost-effective investment for homeowners and businesses alike. Moreover, the unit is designed to be resistant to corrosion and wear, further extending its lifespan and reliability.

The energy efficiency of the Raypak 503-2003 is a crucial characteristic that sets it apart from competitors. Rated with a high efficiency score, this model contributes to lower emissions and is environmentally friendly. It adheres to various energy standards, making it a suitable choice for those looking to reduce their carbon footprint while enjoying reliable water heating.

Noise reduction is another important feature of the Raypak 503-2003. Designed with quiet operation in mind, the unit operates with minimal noise pollution, allowing for a pleasant environment in both residential and commercial spaces.

In summary, the Raypak 503-2003 combines advanced heating technology, user-friendly controls, durability, and energy efficiency into a robust water heating system. This makes it an excellent choice for those in need of dependable and sustainable heating solutions. Whether for daily home use or for larger commercial applications, the Raypak 503-2003 stands out as a leader in its class.