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  3. Water Heater
  4. 400 Series
  5. Instruction Manual

A.O. Smith 400 Series Instruction Manual

Manual is about: Genesis Water Heater

Summary of 400 Series

  • Page 1

    1 printed in u.S.A. 0906 copper boilers for hydronic heating and hot water supply caution text printed or outlined in red contains information relative to your safety. Please read thoroughly before installing and using this appliance. 212511-000 mc bee, sc., renton, wa., stratford-ontario, veldhoven...

  • Page 2: Dimensions/capacities Data

    2 dimensions/capacities data figure 1. Important! Refer to "installation clearances" section of manual (page 7) for recommended service clearances prior to boiler placement. Top view left side table 2. Dimensional data a b c d e f model inches c m inches c m inches c m inches c m inches c m inches c...

  • Page 3

    3 dimensions data for outdoor configuration figure 2. Table 3. Dimensional data a b c d e f g h j model inches cm inches cm inches cm inches cm inches cm inches cm inches cm inches cm inches cm gbo/gwo-1000 14 35.5 31.6 80.3 71.8 182.4 15.5 39.4 39.75 101 58.25 148 15.9 40.83 16 40.64 46.8 118.9 gbo...

  • Page 4: Foreword

    4 table 5: pumping performance guide table 4: recovery capacities temperature rise - degrees °f (°c) input rating water 40°f 50°f 60°f 70°f 80°f 90°f 100°f 110°f 120°f 130°f model btu/hr. (kw) flow (22.2°) (27.7°) (33.3°) (38.8°) (44.4°) (50°) (55.5°) (61.1°) (66.7°) (72.2°) gw - 1000 990,000 (290.1...

  • Page 5: Features/controls

    5 at times you may not be able to smell an lp gas leak. One cause is odor fade, which is a loss of the chemical odorant that gives lp gas its distinctive smell. Another cause can be your physical condition, such as having a cold or diminishing sense of smell with age. For these reasons, the use of a...

  • Page 6

    6 differential pressure switch the differential pressure switch ensures that a sufficient differential exists between the air pressure in the pre-mix chamber and the inlet of the burner for safe, combustion and proper low nox emission. The switch has two pressure taps marked "+" (positive) and "-" (...

  • Page 7: Installation Instructions

    7 drain valve (not supplied) additional drain valves must be obtained and installed on each boiler and tank for draining purposes. Safety relief valves your local code authority may have other specific relief valve requirements not covered below. Warning the purpose of a safety relief valve is to av...

  • Page 8

    8 the authority having jurisdiction, must be provided with a low water cutoff device either as a part of the boiler or at the time of boiler installation. Warning under no circumstances should the equipment room where the boiler is installed ever be under negative pressure. Particular care must be t...

  • Page 9: Venting

    9 see figure 6). At least type b venting must be used with the standard venting option (thru-the-roof) using the national fuel gas code vent tables. Type b vent pipe cannot be used if the boiler is vented horizontally or as a direct vent (see pages 12 through 15). All local utility, state/ provincia...

  • Page 10

    10 power vent (optional) the length of vent used in horizontally vented installations can be extended beyond the lengths shown in tables 11 and 13 by implementing the kits listed below: table 9: power vent kits. Connecting boiler to a common vent do not connect the boiler to a common vent or chimney...

  • Page 11: System Installation

    11 figure 5. Vent termination installation clearances caution direct venting into dead air spaces such as alleys, atriums and inside corners can cause recirculation of flue gases. Recirculation of flue gases will cause sooting, premature failure of the heat exchanger and icing of the combustion air ...

  • Page 12

    12 standard vent - vertical (category i) important! Vent pressure must be maintained between -0.02" w.C. And -0.04" w.C. At 24" (61.0 cm) above boiler collar. • connection for the appliance exhaust vent to the stack must be as direct as possible. Maximum and minimum venting length for category i app...

  • Page 13

    13 table 11. Standard horizontal venting (category iii) standard vent - horizontal (category iii) warning: no substitutions of flue pipe or vent cap material are allowed. Such substitutions would jeopardize the safety and health of inhabitants. • a maximum of two elbows can be used on inlet and outl...

  • Page 14

    14 direct vent - vertical (category i) table 12. Direct vent (vertical exhaust configurations) • connection for the appliance exhaust vent to the stack must be as direct as possible. Maximum and minimum venting length for category i appliances shall be determined per the latest edition of the nation...

  • Page 15

    15 direct vent - horizontal (category iii) warning: no substitutions of flue pipe or vent cap material are allowed. Such substitutions would jeopardize the safety and health of inhabitants. • a maximum of two elbows can be used on inlet and outlet vent piping respectively. Each elbow is equal to 10 ...

  • Page 16: Hydronic Installation

    16 hydronic installation the following is a brief description of the equipment required for installations noted in figure 10. All installations must comply with local codes. Table 14: installation items no. Suggested items for installation 1. Pair of short pipe nipples, pair of boiler loop tees and ...

  • Page 17

    17 large systems with multiple boilers should include main water temperature controls (with or without outdoor reset) to sequence the boiler on and off, in relation to the load on the system. 24 vac system controller (optional) gb models require a field supplied 24vac operating control to be install...

  • Page 18

    18 related to approximate water volume of the system. The system should be turned on to circulate water mix for about one hour and then flush clean with fresh water. Before operating the boiler, the entire system must be filled with water, purged of air and checked for leaks. Do not use stop leak or...

  • Page 19

    19 one genesis (model gw) hot water supply boiler with horizontal tank figure 12. Tank probe installation. Pressure relief valve rating should not exceed pressure capacity of any component in the system. Piping should conform to local codes. Ball valves are shown for servicing boiler. However, local...

  • Page 20

    20 one genesis (model gw) hot water supply boiler with vertical tank figure 13. Single boiler with vertical tank. Pressure relief valve rating should not exceed pressure capacity of any component in the system. Piping should conform to local codes. Ball valves are shown for servicing boiler. However...

  • Page 21

    21 t able 15. Suggested pipe size for multiple gas appliances (natural) t able 16. Suggested pipe size for multiple gas appliances (prop ane gas) length of pipe in feet (metres) maximum cap acity of pipe in btu/hr and kw for gas pressures of 14 in. W .C. (0.5 p si) or less and a pressure drop of 0.5...

  • Page 22

    22 where it is necessary to use more than the average number of pipe fittings i.E. Elbows, tees, and valves in gas supply line, use a pipe larger than specified to compensate for increased pressure drop. Gas control trains are unique for each genesis ii unit. Stages one, two and three run sequential...

  • Page 23

    23 gb/gw 2100 gb/gw 2500 gb/gw 1000 - 1500 gas manifold assembly gb/gw 1850 figure 14. Gb/gw 1000 - 2500 gas manifold assembly diagrams..

  • Page 24

    24 genesis gb/gw 1000-2500 series 400 wiring diagram figure 15..

  • Page 25

    25.

  • Page 26

    26 genesis gb/gw 1000-2500 series 400 schema tic diagram figure 16..

  • Page 27

    27.

  • Page 28

    28 figure 17. Ccb central control board.

  • Page 29

    29 figure 18. Fcb flame control board diagram.

  • Page 30

    30 figure 19. Pdb power distribution board diagram.

  • Page 31: Operation

    31 fuse protection the 24vac circuitry is protected with a 3 amp fuse on the flame control boards (fcb) and a 7.5 amp fuse on the central control board. If the fuse opens, a red led located near the fuse will light. See figures 17 and 18. If the red led is illuminated, replace the fuse. Repeated fai...

  • Page 32: Operating Instructions

    32 lighting instructions for the g(b/w) 1000 through 2500 models a. This appliance does not have a pilot. It is equipped with an ignition device which automatically lights the burner. Do not try to light the burner by hand. B. Before operating: smell all around the appli- ance area for gas. Be sure ...

  • Page 33: Operating Instructions

    33 lighting instructions for the g(b/w) 1000 through 2500 models for your safety read before operating operating instructions to turn off gas to appliance warning: if you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or loss of life...

  • Page 34: Control System

    34 table 20. Risk of scalds. Temperature time to produce 2nd & 3rd setting degree burns on adult skin over 170°f (77°c) nearly instantaneous 160°f (71°c) about 1/2 second 150°f (66°c) about 1-1/2 seconds 140°f (60°c) less than 5 seconds 130°f (54°c) about 30 seconds 120°f (49°c) or less more than 5 ...

  • Page 35

    35 required): the ccb accepts analog temperature inputs from up to three sensors (inlet, outlet and tank). • eco input (ccb - required): the eco (energy cut off) is a hi-limit switch, which is located inside the outlet probe. It is a normally closed switch that opens if the probe is exposed to a tem...

  • Page 36

    36 ccb - three position dipswitch (flame control section) sw2: this dipswitch is similar to the fcb dipswitches described below, but with only three switches being used: the number of blower speeds (switch #3), hi gas option (switch #2) and a spare (switch #1). Only the blower speed and hi gas optio...

  • Page 37

    37 operating sequence note: the following sequence is based on a three-stage system. 1. The emc 5000 controller has four modes of operation: initialization, standby, running, and service. The internal ccb and fcb micros control these modes through a sequence of steps (or states) which are further de...

  • Page 38

    38 followed by 15-second inter-purge period, then the system returns to step 7, if the "trial for ignition" dipswitch is set for three (3) tries. If the dipswitch is set for one (1) trial, the system will declare an error and boiler will require resetting the control. 10. If a flame is detected, sta...

  • Page 39

    39 • menu screen: displayed when the user presses the "menu" key. This screen is the selection point for the other 9 screens. • temperature screen: displays the sensed temperatures of the outlet, inlet, and tank probes. Also displayed is the calculated delta t (outlet minus inlet) for the system. Sh...

  • Page 40

    40 • soft fault state: (see "fault description" section for list of soft and auto reset faults.) the ccb turns off the powered vent and the iri gas. The pump remains on for the selected post-circulate time to cycle the hot water out of the boiler. The fcb's are commanded to shut down and the alarm o...

  • Page 41

    41 6. Use the up or down key to select the value you wish to enter. 7. Touch the select key to accept and store the new value. • operating differential setpoints: each of the two stages has an independent operating differential setpoint. Operating differential setpoint adjustment procedure each of t...

  • Page 42

    42 when an error is detected. It will also go to this screen upon power-up if an error was still valid when power was turned off. Note: errors are cleared from this screen by pressing the "select" key. • error history screen: this screen displays a list of the last 9 errors (with time stamps) that h...

  • Page 43

    43 “low 24vac” voltage from transformer less than 18 vac continuous auto reset check transformer output. Should be over 24vac. May be caused by excessive current drain or a faulty transformer “brown out reset” indicates a brown out reset occurred - - - - none caused by a momentary dip in voltage on ...

  • Page 44

    44 preventative maintenance this is an induced burner and the flame is not supposed to be directly on the burner. The flame should be just above the burner deck approximately 1/8” and blue in color. See figure 22. Visually check flame characteristics through the view port located under the left-hand...

  • Page 45

    45 after placing the boiler in operation, check the ignition system safety shut-off devices for proper operation. To accomplish this with the main burners operating, close the valve on the manifold. Within four seconds the main burners should extinguish. If this does not occur immediately, discontin...

  • Page 46

    46 all of the hardness (lime). For this reason it is recommended that a regular schedule for deliming be maintained. The time between cleaning will vary from two to six months depending upon water conditions and usage. A change of approximately 5 o f (3°c) in the normal temperature rise through the ...

  • Page 47

    47 new boiler limited warranty a. O. Smith corporation, the warrantor, extends the following limited warranty to the owner of this hydronic boiler: 1. If within ten years after initial installation of the boiler, the heat exchanger shall prove upon examination by the warrantor to be defective in mat...

  • Page 48

    48 500 tennessee waltz parkway, ashland city, tn 37015 phone: 800-433-2545 www.Hotwater.Com e-mail: parts@hotwater.Com.