START UP/ FLAME RECOVERY/ SAFETY LOCKOUT

START UP - HEAT MODE

When a call for heat is received from the thermostat supplying 24 volts to to UGB J5.6, the UGB will enable blower run at prepurge speed, which will cause the blower prover switch closing, and allow 24vac power from the T-stat to TH/W terminal of the control module. The control will reset, perform a self check routine, flash the diagnostic LED once in the first two seconds, and a pre-purge delay begins. 20 seconds after high speed prepurge, UGB will send a ignition low speed PWM to blower for preparing the ignition sequence. Following the 30 seconds pre-purge period, the gas valve is energized and sparks commence for the trial for ignition period.

When flame is detected during the trial for ignition, the sparking process is terminated and the UGB high speed signal is energized after a 5 second dwell period and the heater will run at the rated fire rate. The thermostat and burner flame are constantly monitored to assure the system continues to operate properly. When the thermostat is satisfied and the demand for heat ends, the gas valve and UGB speed signals are de-energized immediately.

FAILURE TO LIGHT - LOCKOUT

MULTI TRIAL CONTROL

Should the burner fail to light, or if flame is not detected during the first trial for ignition period, the gas valve is de-energized. The control then goes through an interpurge delay before another ignition attempt. The control will attempt two additional ignition trials before going into lockout and the valve relay will be de-energized immediately. This ignition control has an automatic reset. If the thermostat is still calling for heat after 15 minutes the control will automatically reset and attempt to ignite the burner.

FLAME FAILURE- RECYCLE MODE

This control has the "recycle after loss of flame" function, upon loss of an established burner flame, the gas valve is de-energized and the control proceeds to interpurge before attempting to relight the burner. The ignition control will allow three tries for ignition including inter-purges. If the burner relights, normal operation resumes. If the burner does not relight, the control will go into lockout as described in "failure to light".

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Servicing should only be performed by a Qualified Service Technician

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American Water Heater ULTRA LOW NOx SERIES 104, BCL manual Start UP/ Flame RECOVERY/ Safety Lockout, Start UP Heat Mode
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381T1546NOX, 395T1996NOX, BCL, 381T1206NOX, 395T2506NOX specifications

The American Water Heater Ultra Low NOx Series represents a significant advancement in water heating technology, aiming to meet stringent environmental regulations while delivering reliable hot water for residential applications. Models such as the 104,395T1806NOX, 395T2506NOX, 381T1206NOX, and BCL are designed to prioritize efficiency, performance, and compliance with the latest emission standards.

One of the defining features of the Ultra Low NOx Series is its innovative combustion technology. These water heaters utilize a state-of-the-art gas burner that dramatically reduces nitrogen oxide (NOx) emissions, ensuring compliance with local and federal regulations. This technology not only benefits the environment but also contributes to improved indoor air quality.

Efficiency is a hallmark of the Ultra Low NOx Series, with models designed to maximize energy savings while delivering consistent hot water. They feature a user-friendly, adjustable thermostat, providing homeowners with the ability to set their desired water temperature for optimal comfort. In addition, the insulation on these water heaters is designed to minimize heat loss, ensuring that energy consumption is kept to a minimum.

The Ultra Low NOx models are equipped with an easy-to-use digital control panel that allows homeowners to monitor and adjust settings with ease. This convenience is enhanced by advanced diagnostics, which provide real-time alerts regarding system performance and maintenance needs. This proactive approach helps extend the lifespan of the unit and enhances reliability.

Safety is another crucial characteristic of the Ultra Low NOx Series. Each model is equipped with safety features such as a flame rollout switch and a fully automatic gas shut-off, which ensure that the system operates safely under various conditions.

In terms of installation and maintenance, these models are designed with user-friendly features, making the process simpler for technicians. The compact design allows for flexible installation options, even in tighter spaces.

Overall, the American Water Heater Ultra Low NOx Series, including the 104,395T1806NOX, 395T2506NOX, 381T1206NOX, and BCL models, represents an excellent choice for homeowners seeking an efficient, reliable, and environmentally responsible water heating solution. With a focus on reducing emissions and enhancing performance, these models are built to meet the demands of today's conscientious consumers.
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