CONFINED SPACE

When drawing combustion and dilution air from inside a conventionally constructed building to a confined space, such a space shall be provided with two permanent openings. ONE WITHIN 12 INCHES OF THE ENCLOSURE TOP AND ONE WITHIN 12 INCHES OF THE ENCLOSURE BOTTOM. Each opening shall have a free area of one square inch per 1000 Btuh of the total input of all appliances in the enclosure, but not less than 100 square inches.

If the confined space is within a building of tight construction, air for combustion, ventilation and power venter dilution must be obtained from outdoors. When directly communicating with the outdoors or communicating through vertical ducts, two permanent openings, located in the above manner, shall be provided. Each opening shall have a free area of not less than one square inch per 4000 Btuh of the total input of all appliances in the enclosure. If horizontal ducts are used, each opening shall have a free area of not less than one square inch per 2000 Btuh of the total input of all appliances in the enclosure.

3.This unit may NEVER be connected to any existing heating system or component(s) previously used with a non-potable water heating appliance.

4.When the system requires water for space heating at temperatures higher than required for domestic water purposes, a tempering valve must be installed. Please refer to Fig. 2 for suggested piping arrangement.

WATER CONNECTIONS

Refer to figure 1 for typical installation. A suitable pipe thread sealant must be used to prevent leakage.

WATER (POTABLE) HEATING AND SPACE HEATING

1.All piping components connected to this unit for space heating applications shall be suitable for use with potable water.

2.Toxic chemicals, such as those used for boiler treatment, shall NEVER be introduced into this system.

FIGURE2

CLOSED WATER SYSTEM

A closed system will exist if a back-flow preventer (check valve), pressure reducing valve, or other similar device is installed in the cold water line between the water heater and the street main (or well). Excessive pressure may develop due to the thermal expansion of heated water causing premature tank failure or intermittent relief valve operation. This type of failure is not covered by the limited warranty. An expansion tank may be necessary in the cold water supply to alleviate this situation, see Fig. 1. Contact the local plumbing authority.

If the temperature and pressure relief valve on the appliance discharges periodically, this may be due to thermal expansion in a closed water supply system. Contact the water supplier or local plumbing inspector on how to correct situation. DO NOT PLUG THE TEMPERATURE AND PRESSURE RELIEF VALVE.

GAS CONNECTIONS

The minimum gas supply pressure for input adjustment is 5.0" W.C. for natural gas (11.0" W.C. for propane).

THE HEATER IS NOT INTENDED FOR OPERATION AT HIGHER THAN 14" WATER COLUMN SUPPLY PRESSURE. EXPOSURE TO HIGHER GAS SUPPLY PRESSURE MAY CAUSE DAMAGE TO THE CONTROL WHICH COULD RESULT IN FIRE OR EXPLOSION. If overpressure has occurred such as through improper testing of gas lines or emergency malfunction of the supply system, the control must be checked for safe operation. Make sure that the outside vents on the supply regulators and the safety vent valves are protected against blockage. These are parts of the gas supply system not the heater. Vent blockage may occur during ice storms.

IT IS IMPORTANT TO GUARD AGAINST CONTROL FOULING FROM CONTAMINANTS IN THE GAS WAYS. SUCH FOULING MAY CAUSE IMPROPER OPERATION, FIRE OR EXPLOSION.

All piping must comply with local codes and ordinances or with the National Fuel Gas Code (ANSI Z223.1 NFPA-54) whichever applies.

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A.O. Smith FPSH - 75 Confined Space, Water Connections, Water Potable Heating and Space Heating, Closed Water System
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FPSH - 75 specifications

The A.O. Smith FPSH-75 is a prominent model in the lineup of water heaters offered by A.O. Smith, a company renowned for its innovative approach to water heating solutions. This residential water heater is designed to meet the demands for both efficiency and performance, making it a popular choice for households seeking reliable hot water supply.

One of the standout features of the FPSH-75 is its impressive 75-gallon capacity, which is suitable for larger households or properties that require high volumes of hot water. This feature ensures that multiple fixtures can be used simultaneously without the worry of running out of hot water. Additionally, the unit is equipped with a powerful heating element that provides rapid heating, making it efficient for quick recovery times even during peak usage.

The FPSH-75 utilizes advanced insulation technology to minimize heat loss, which enhances energy efficiency. This means that the water heater can maintain the desired water temperature while consuming less energy. As a result, homeowners can enjoy significant savings on their energy bills, all while benefiting from consistent hot water availability.

This model is also designed with user-friendly controls, allowing homeowners to set and adjust their water temperature preferences easily. The intuitive interface ensures that users can operate the unit without hassle, optimizing their water heating experience.

Safety is also a critical consideration in the design of the FPSH-75. It comes with built-in safety features, including a temperature and pressure relief valve, which helps prevent potential hazards associated with overheating and excessive pressure buildup. Moreover, the durable construction of the tank is engineered to withstand corrosion, extending the lifespan of the water heater.

Installation is made convenient with the FPSH-75, as it is compatible with various plumbing setups, making it adaptable for a range of home designs. The model has been certified for meeting the industry standards, ensuring reliability and peace of mind for end-users.

In summary, the A.O. Smith FPSH-75 is an exceptional water heating solution, ideal for families and homes needing robust hot water delivery. Its combination of high capacity, energy efficiency, user-friendly controls, and safety features make it a top contender among residential water heaters, ensuring that homeowners can enjoy comfort and convenience without compromise.
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