4.Proof of Air Pressure Switch - The control will look for a signal from the airflow-proving switch, indicating that the blower is operating:

a.When the airflow generated by the blower is sufficient to cause the differential air switch to close, the 15 - second pre-purge delay will start.

b.During this period any flue products or combustible gases which may have settled in the water heater are evacuated.

5.Heat-Up- Following the pre-purge delay, the hot surface igniter will be energized:

a.The flame control will monitor the current applied to the hot surface igniter.

b.If the flame control determines the proving current meets the threshold, a dwell time delay starts to assure the hot surface igniter has sufficient time to reach ignition temperature.

6.Ignition - When dwell time is completed a 4-second Trial for Ignition (TFI) period is initiated:

a.The Delay-On (Low Fire Hold) Relay and the Gas Safety Valves are energized.

b.During TFI the flame safeguard control will monitor the flame using flame rectification through the hot surface igniter.

c.If the flame control senses the presence of flame before the end of the TFI period, the igniter will be de- energized and the flame control will continue to monitor the flame, through the igniter, until the operating thermostat ends the call for heat condition.

7.Loss of Flame Signal:

a.If the igniter fails to sense flame at any time, the igniter and gas valve will be de-energized and the flame control will reset and begin the call-for-heat sequence again. This will occur 3 times (one time if CSD-1) before the flame control will lockout.

b.When the call for heat condition ends or flame failure occurs following the third TFI period (one time if CSD- 1), a 30-second post-purge period will begin. This period of blower operation will exhaust any remaining combustion products from the system.

8.Delay-On Relay - Once the Delay-On (Low Fire Hold) Relay has timed out, it energizes the Modulation Release Relay (SPDT) to enable the analog signal from the TempTrac to the VFD to regulate the speed of the blower.

a.The TempTrac will continue to monitor the stored water temperature in the tank.

b.When the setpoint temperature is reached the call-for-heat signal to the flame safeguard control is discontinued.

c.The flame safeguard control deenergizes the VFD blower system and the gas valve, thereby suspending burner operation.

d.As heat is transferred to the building, the water heater loop temperature will fall below the set point. The TempTrac will sense this condition and begin the call-for-heat sequence again.

9.Flame Safeguard LED Diagnostic Indicator - If the Fenwal Flame Safeguard Control at any time during the operating sequence senses an improper operating state and locks out, the diagnostic red LED located on the control board will flash to indicate one of the following conditions exist:

LED INDICATION

FAULT MODE

On

Normal Operation

OFF

Internal Control Failure – check power

1

Flash

Airflow Fault

 

 

 

2

Flashes

Erroneous Flame Signal

3

Flashes

Ignition Lockout

4

Flashes

Hot Surface Igniter Fault

 

 

 

5

Flashes

Low Voltage (24 VAC)

6

Flashes

Valve Relay Problem

 

 

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PV500-44U 06/12

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PVI Industries PV500-44U manual Loss of Flame Signal, LED Indication Fault Mode
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PV500-44U specifications

PVI Industries is a well-established name in the manufacturing of innovative water heating solutions, and one of its standout products is the PV500-44U. This commercial water heater is specifically designed to meet the demands of medium to large-scale facilities, ensuring efficient and reliable hot water delivery.

The PV500-44U is a high-capacity, gas-fired water heater, offering a remarkable output of up to 500,000 BTU per hour. This impressive capacity makes it suitable for a variety of applications, including hospitality, healthcare, and industrial washing. With such power, it provides continuous hot water, which is vital in settings that require consistent hot water availability.

One of the key features of the PV500-44U is its robust construction. The unit is designed with high-quality stainless steel, which provides durability and resistance against corrosion. This is crucial for maintaining long-term reliability, especially in environments where water quality may vary. Additionally, the water heater utilizes a sophisticated insulation system that minimizes heat loss, ensuring that energy consumption remains efficient.

The PV500-44U incorporates advanced technologies aimed at enhancing performance and user control. It features a state-of-the-art digital control system that allows for precise temperature settings and monitoring. This system not only ensures optimal performance but also enhances safety by providing alerts for any operational anomalies.

Another notable characteristic of the PV500-44U is its eco-friendly design. It is engineered to meet the latest environmental regulations, which helps reduce carbon emissions and energy consumption. The unit’s high thermal efficiency contributes to lower operating costs, making it an economical choice for businesses looking to manage their energy expenses effectively.

In terms of maintenance, the PV500-44U offers user-friendly access to components, simplifying routine servicing and repair tasks. This thoughtfully designed structure helps extend the lifespan of the unit and minimize downtime, which is critical for maintaining hot water availability in commercial settings.

Overall, the PVI Industries PV500-44U stands out as a reliable and efficient water heating solution that effectively meets the high demands of commercial applications. Its combination of powerful output, robust construction, advanced technology, and eco-friendly features makes it a premium choice for businesses seeking quality and efficiency in their hot water systems.
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