HIGH LIMIT SWITCH (E.C.O.)
The top immersion well of the upper probe also contains the high limit (energy cutoff) sensor. The high limit switch interrupts the main burner gas flow should the water temperature reach approximately 199°F/93°C.
Should the high limit switch activate, it must be reset by cycling power to the unit. The water temperature must drop below 180°F/ 82°C before the controller can be reset.
Continued manual resetting of the high limit control, preceded by higher than usual water temperature is evidence of high limit switch operation. For example, a malfunction of the control system allowing the gas valve to stay open could cause water temperature to rise until the high limit switch opens. Contact your dealer or servicer if continued high limit switch operation occurs.
DISHWASHING MACHINE REQUIREMENT
All dishwashing machines meeting the National Sanitation Foundation requirements are designed to operate with water flow pressures between 15 and 25 pounds per square inch (103 kPa and 173 kPa). Flow pressures above 25 pounds per square inch (173 kPa), or below 15 pounds per square inch (103 kPa), will result in improperly sanitized dishes. Where pressures are high, a water pressure reducing or flow regulating control valve should be used in the 180°F (82°C) line to the dishwashing machine, and should be adjusted to deliver water between these limits.
The National Sanitation Foundation also recommends circulation of 180°F (82°C) water. Where this is done, the circulation should be very gentle so that it does not cause any unnecessary turbulence inside the water heater. The circulation should be just enough to provide 180°F (82°C) water at the point of take- off to the dishwashing machine. Adjust flow by means of the plug cock in the circulating line. (See INSTALLATION DIAGRAMS section.)
CIRCULATING PUMP
FIGURE 3
AUTOMATIC AIR BLEED VALVE
A circulating pump is used when a system requires a circulating loop or there is a storage tank used in conjunction with the heater. Refer to the piping diagrams at rear of manual for electrical hookup information and install in accordance with the current version of the National Electric Code NFPA No. 70.
All bronze circulators are recommended for use with commercial water heaters.
Although circulators are oiled and operated by the manufacturer some circulators must be oiled again before being operated. Please refer to manufacturer's instructions.
PLUMBING MANIFOLD ASSEMBLY
FLOW DIAGRAM
The plumbing manifold assembly is composed of several components with each having a unique function. Please see Figures 3, 5, and 6 to observe the water flow to the plumbing manifold assembly and the components that make it up.
The tank assembly utilizes an automatic air bleed valve. The purpose for this automatic air bleed valve is to allow air to escape the tank when the unit is filled with water. When the unit is drained, the opposite occurs with the valve allowing air to replace the drained water. It removes the pressure vacuum that occurs in the system causing incomplete drainage. This valve is automatic which allows it to sense when the tank assembly is filled with water, see Figure 4.
FIGURE 4
6