SEDIMENT TRAPS

A sediment trap shall be installed as close to the inlet of the water heater as practical at the time of water heater installation. The sediment trap shall be either a tee fitting with a capped nipple in the bottom outlet or other device recognized as an effective sediment trap. If a tee fitting is used, it shall be installed in conformance with one of the methods of installation shown in Figures 27, 28 and 29.

FIGURE 27. GAS PIPING WITH FLEXIBLE CONNECTOR.

FIGURE 28. GAS PIPING WITH ALL

BLACK IRON PIPE TO GAS CONTROL.

FIGURE 29. ALTERNATIVE SEDIMENT TRAP LOCATION

Contaminants in the gas lines may cause improper operation of the gas control valve/thermostat that may result in fire or explosion. Before attaching the gas line be sure that all gas pipe is clean on the inside. To trap any dirt or foreign material in the gas supply line, a drip leg (sometimes called a sediment trap) must be incorporated in the piping. The drip leg must be readily accessible. Install in

accordance with the “Gas Piping” section. Refer to the current edition of the Natural Gas and Propane Installation Code (CAN/CSA B149.1-current edition).

FUEL CONVERSION INSTRUCTIONS

FROM NATURAL GAS TO PROPANE (L.P.) GAS

This water heater has been factory equipped to operate with the type gas indicated in the “EQUIPPED FOR” area of the model rating plate located near the gas control valve/thermostat. The indicated gas may be either Natural or Propane (L.P.). By following the conversion instructions in this manual or the instructions near the gas control valve/thermostat, the water heater must be converted if it is to be used with the opposite gas. DO NOT USE THIS WATER HEATER WITH ANY GAS OTHER THAN THE ONE LISTED ON THE MODEL RATING PLATE. Failure to use the correct gas can cause problems which can result in DEATH, SERIOUS BODILY INJURY, OR PROPERTY DAMAGE. If you have any questions or doubts consult your gas supplier or gas company.

Read and follow detailed conversion instructions located on the water heater and also in the instruction manual in their entirety before starting the conversion.

Conversion kit with necessary parts are in a bag attached to the drain valve.

FOR 30 GALLON HEATER:

Orifice size: #40 for Natural / #52 for Propane (L.P.),

if converted - Propane Rate: 30,000 BTU.

FOR 40 GALLON HEATER:

Orifice size: #38 for Natural / #51 for Propane (L.P.),

if converted - Propane Rate: 32,000 BTU.

FOR 50 GALLON HEATER:

Orifice size: #35 for Natural / #51 for Propane (L.P.),

if converted - Propane Rate: 38,000 BTU.

Step 1. Turn gas control knob “A” to “PILOT”. Depress and turn “OFF”, see Figure 30 page 19.

Step 2. Remove outer and inner access doors from water heater.

Step 3. Remove burner assembly from water heater control by first removing 6 screws holding inner door to heater, then loosening 3/4” nut “H” holding burner assembly to control, see figures 31 and 32. Loosen pilot tube nut “J” and thermocouple nut “K” at control. Disconnect wire to Piezo Igniter.

Step 4. Remove screws “D” disengaging manifold from burner, see Figure 33 page 19.

Step 5. Remove orifice “E”, see Figure 34 page 19 using 3/8” wrench. Install orifice marked “L.P.” found in the bag into manifold. Tighten securely. Secure burner to manifold with screws “D”.

Step 6. Loosen pilot tube nut “F”, see Figure 34 page 19. Remove orifice “G” and replace with red colored orifice found in bag. Reinstall nut “F” and tighten securely.

Step 7. Make sure all connections are tightened securely, and reinstall burner assembly into water heater. Position end of manifold inside bracket as shown in Figure 33 page

19.Reinstall manifold into control and tighten 3/4” nut (“H”) securely. Recheck to see that end of manifold is still inside bracket as shown in Figure 33 page 19. Reinstall pilot tubing and thermocouple into control, see Figure 31 page 19. Connect wire to Piezo Igniter. Reinstall inner door using the 6 screws removed in Step 3.

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A.O. Smith FMD 50, FMD 40, FMD 30 Sediment Traps, For 30 Gallon Heater, For 40 Gallon Heater, For 50 Gallon Heater
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FMD 40, FMD 50, 315795-000 MH, FMD 30 specifications

A.O. Smith is a renowned brand in the field of water heating solutions, offering a range of efficient and durable water heaters tailored to meet diverse consumer needs. Among its extensive lineup, the A.O. Smith FMD series showcases several commendable models, including the FMD 30, FMD 40, and FMD 50, each boasting unique features and advanced technologies.

The A.O. Smith FMD 30 is a compact water heater designed for smaller households or limited spaces. With a 30-gallon capacity, it is engineered to provide ample hot water for everyday needs such as bathing, washing dishes, and laundry. The heater employs advanced insulation technology, ensuring heat retention and energy efficiency. The thermostatic control system allows users to easily adjust the water temperature to their preference, ensuring comfort while promoting safety.

Moving to the A.O. Smith FMD 40, this model offers an increased capacity of 40 gallons, making it an ideal choice for medium-sized families. It incorporates A.O. Smith’s cutting-edge Durapower glass coating, which protects the tank from corrosion, ultimately extending its lifespan. The FMD 40 also features an enhanced heating element design that ensures rapid heating and consistent water temperature, making it perfect for bustling households.

The A.O. Smith FMD 50 takes things a step further, providing 50 gallons of hot water storage and designed for larger families or high-demand applications. This model integrates advanced technology features like a smart thermal control system that optimizes energy usage, ensuring that hot water is available when you need it without unnecessary power consumption. With robust construction materials, the FMD 50 is built to last, even in harsh conditions.

All models in the A.O. Smith FMD series prioritize user convenience. They come equipped with easy-to-read digital displays for monitoring temperature and status, along with built-in safety features such as automatic shut-off mechanisms. Installation is straightforward, and each unit adheres to energy efficiency standards, which help reduce utility bills while being environmentally friendly.

In summary, the A.O. Smith FMD series, including the FMD 30, FMD 40, and FMD 50, represents a commitment to quality and innovation. With their varying capacities and advanced technologies, these water heaters cater to a wide range of household needs, delivering reliable hot water solutions while maintaining energy efficiency and durability. Investing in an A.O. Smith FMD water heater not only guarantees comfort but also highlights a commitment to sustainability.
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