A.O. Smith HW 399 Specifications

11111PLACE THESE INSTRUCTIONS ADJACENT TO BOILER ANDNOTIFY OWNER TO KEEP FOR FUTURE REFERENCEA DIVISION OF A.O. SMITH CORPORATIONMC BEE, SC SEATTLE

1010101010 2A.SIZING GAS SUPPLY LINE (For single boiler installations andfor installations of multiples of two or three of same size boilers).Use tabl

1111111111• In table 6, select the row showing the distance to the mostremote outlet or the next longer distance if the table does notgive the exact l

12121212127. Set primary system temperature control dial (thermostat) todesired setting. WARNINGDO NOT INCREASE GAS PRESSURE ABOVE THAT SPECIFIEDON T

1313131313After it has been determined that each appliance remainingconnected to the common venting system properly vents whentested as outlined above

1414141414MODEL HW/HWB-610 BOILER Input: 610,000 Btuh Draft Hood Outlet 12"Required Connector or Smoke Pipe DiameterConnector Total Vent Heig

1515151515VENTING MAINTENANCE - STANDARD VENTINGIt is recommended that the heating surfaces and vent piping ofthe appliance be checked every six month

1616161616The storage tank temperature and pressure (T & P) relief valvemust comply with the applicable construction provisions of theStandard for

1717171717CONNECTION DIAGRAMHWB & HW-300, -399, -420, -500 & -610(NATURAL GAS)SINGLE STAGE I.I.D. - ROBERTSHAW® GAS VALVEHWB & HW-300, -39

1818181818CONNECTION DIAGRAMHWB, HW-420,-520, -610(PROPANE GAS)SINGLE STAGE PROPANE - ROBERTSHAW GAS VALVE24 VOLT -HW, HWB-420, -520, -610 CANADIAN MO

1919191919SINGLE STAGE PROPANE ROBERTSHAW GAS VALVE24 VOLT - HWB, HW-300, 399 CANADIAN MODELSFIGURE 11ACONNECTION DIAGRAM HWB & HW 300, 399(PROPAN

22222ROUGH-IN DIMENSIONS TABLE 2, SPECIFICATIONS - CANADIAN MODELS ONLYMaximumMaximum I.A.S. Maximum Max. Heat Transfer Max. Heat TransferModel Type

2020202020HW-300, HW-399, HW-420, HW-500 & HW-670(NATURAL GAS)SINGLE STAGE I.I.D. - ROBERTSHAW GAS VALVEHW-300, -399, -420, -520 & 670 (NATURA

2121212121HW-300, HW-399, HW-420, HW-500 & HW-670(PROPANE GAS)FIGURE 12SINGLE STAGE I.I.D. - ROBERTSHAW GAS VALVEHW-300, -399, -420, -520 & 67

22222222222.LINEAR-TEMP INSTALLATIONSControl for these systems is decided mainly by the type of buildingsystem controlling that is desired. A single

2323232323NOTE:1. Building temperature controls supply electric power to buildingcirculator.2. Main flow switch proves main water flow before energizi

2424242424NOTE:1. Building temperature controls supply electricpower to building circulator.2. Main flow switch proves main water flow beforeenergizin

2525252525CER-TEMP 80 - 1 UNIT INSTALLATION - FOR HOT WATER SUPPLY APPLICATIONCANADIAN MODELS, JUNCTION BOX W/6 TERMINALSFIGURE 17FIGURE 19CER-TEMP 80

2626262626CER-TEMP 80 - 2 OR 3 UNIT INSTALLATION - FOR HOT WATER SUPPLY APPLICATIONCANADIAN MODELS, JUNCTION BOX W/6 TERMINALSFIGURE 20

2727272727FIGURE 21SCHEMATICCANADIAN MODELS, JUNCTION BOX W/6 TERMINALS

2828282828CER-TEMP 80 - 2 OR 3 UNIT INSTALLATION CONNECTION DIAGRAM (FOR HOT WATER SUPPLY APPLICATION)U.S. MODELS, JUNCTION BOX W/4 TERMINALSFIGURE 22

2929292929CER-TEMP 80 - 2 OR 3 UNIT INSTALLATION SCHEMATIC DIAGRAM (FOR HOT WATER SUPPLY APPLICATION)U.S. MODELS, JUNCTION BOX W/4 TERMINALSFIGURE 23

33333 TABLE 3, RECOVERY CAPACITIES - CANADIAN MODELS ONLYInput Temp. (C) 11 17 22 26 33 39 44 50 56 61 67 72 78Model (Btu/Hr.) Rise (F) 20 30 40 50 60

3030303030FIGURE 24BOOSTER - RECOVERY WIRING DIAGRAMCANADIAN MODELS, JUNCTION BOX W/6 TERMINALSSHURE-TEMP BOOSTER - RECOVERY WIRING DIAGRAM(TWO TEMPER

3131313131BOOSTER - RECOVERY WIRING DIAGRAMU.S. MODELS, JUNCTION BOX W/4 TERMINALSFIGURE 26SHURE - TEMP BOOSTER - RECOVERY WIRING DIAGRAMTWO-TEMPERATU

3232323232WATER LINE CONNECTIONSThis section provides detailed installation diagrams for typicalmethods of application for the unit using a Cer-Temp 8

3333333333USE ANTI-SCALD VALVE(S) in the hot water system to reduce therisks of scalds at points of use such as lavatories, sinks andbathing facilitie

3434343434FIGURE 29IMPORTANTTHE INSTALLATION OF SAFETY FLOW SWITCH AS SHOWNIS REQUIRED TO PROTECT THE BOILER IN CASE OF WATERSERVICE INTERRUPTION OR C

3535353535FIGURE 30ONE HW-300, HW-399, HW-420, HW-520, HW-610 OR ONE HW-670 UP-FLOW MODELCOMMERCIAL BOILER WITH HORIZONTAL TANKWIRING - FIGURES 17, 1

3636363636TWO HW-399's, HW-420's, HW-520's, HW-610's or HW-670's UP-FLOW MODELCOMMERCIAL BOILER WITH VERTICAL TANK, CER-TEMP

3737373737FIGURE 32TWO HW-300's, HW-399's, HW-420's, HW-520's, HW-610's OR HW-670's UP-FLOW MODELCOMMERCIAL BOILER WITH

3838383838THREE HW-520's, HW-610's OR HW-670's UP-FLOW MODELCOMMERCIAL BOILER WITH VERTICAL TANK, CER-TEMP 80IMPORTANTTHE INSTALLATION

3939393939THREE HW-520's, HW-610's OR HW-670's UP-FLOW MODELCOMMERCIAL BOILER WITH HORIZONTAL TANK, CER-TEMP 80IMPORTANTTHE INSTALLATIO

44444 CAUTIONTEXT PRINTED OR OUTLINED IN RED CONTAINS INFORMATION RELATIVETO YOUR SAFETY. PLEASE READ THOROUGHLY BEFORE USINGAPPLIANCE.Detailed insta

4040404040FIGURE 35WIRING - FIGURE 25 OR 27INSTALL IN ACCORDANCEWITH ALL LOCAL CODESBOOSTER RECOVERY SYSTEM (PATENTED)TWO TEMPERATURE SYSTEM WITHOUT R

4141414141FIGURE 36BOOSTER RECOVERY SYSTEM (PATENTED)TWO TEMPERATURE SYSTEM WITHOUT RECIRCULATIONONE HW-300, HW-399, HW-420, HW-520, HW-610 OR HW-670

4242424242FIGURE 37BOOSTER RECOVERY SYSTEM (PATENTED) - TWO TEMPERATURE SYSTEM WITHOUT RECIRCULATIONONE HW-300, HW-399, HW-420, HW-520, HW-610 OR HW-6

43434343434 FLOW REGULATING PLUG COCK(For Boiler Flow Rate Adjustment)A slight closing of this valve may be necessary to set properwater flow rate for

4444444444FIGURE 39WITH TWO VERTICAL TANKSWITH THREE VERTICAL TANKS DANGERTEMPERATURE SETTING SHOULD NOTEXCEED SAFE USE TEMPERATURE ATFIXTURES. SEE T

4545454545TWO HORIZONTAL TANK INSTALLATIONTHREE HORIZONTAL TANK INSTALLATIONFIGURE 40 DANGERTEMPERATURE SETTING SHOULD NOT EXCEED SAFEUSE TEMPERATURE

4646464646IMPORTANTIT IS RECOMMENDED THAT A QUALIFIED PERSON PERFORMTHE INITIAL FIRING OF THE BOILER. AT THIS TIME THE USERSHOULD NOT HESITATE TO ASK

4747474747LIGHTING AND OPERATING INSTRUCTIONS (NATURAL AND PROPANE GAS WITH I.I.D.) WARNING: HOT WATER CAN PRODUCE 3rd DEGREEBURNS IN 6 SECONDS AT 14

4848484848LIGHTING AND OPERATING INSTRUCTIONS PROPANE (LP) STANDING PILOT MODELS WARNING: HOT WATER CAN PRODUCE 3rd DEGREEBURNS IN 6 SECONDS AT 140° F

49494949494. Adjust pilot flame.To adjust the pilot flame, remove the cap screw from thepilot adjusting valve and turn to deliver a sufficient flameat

55555LOCATIONWhen installing the boiler, consideration must be given to properlocation. Location selected should be as close to the stack orchimney a

5050505050FIGURE 43DThe purpose of checking the current ahead and after the protectorswitch is to measure the millivolt drop across the contacts. This

5151515151• If lamp does not light when reset button is depressed, attach the test flashlight leads to the protector switch terminals. If lamp d

5252525252NORMAL OPERATING SEQUENCE WITH INTERMITTENTIGNITION CONTROLS (I.I.D.)1. System control calls for boiler operation.2. Spark begins at pilot b

5353535353 PROTECTOR SWITCHFIGURE 48PRESSURE REDUCING VALVEThe screen in the pressure reducing valve may require occasionalclean

5454545454To adjust the flow rate setting:1. Remove the flow switch cover.2. For higher flow rate—turn the range adjusting screw clockwise.3. For lowe

5555555555GENERAL MAINTENANCEThese boilers are designed to give many years of efficient andsatisfactory service when properly operated and maintained.

5656565656The time between cleaning will vary from two to six monthsdepending upon water conditions and usage. A change ofapproximately 50F in the no

5757575757TROUBLESHOOTINGCER-TEMP 80 RECOVERY SYSTEM CHECKOUT PROCEDUREUse this checkout for Cer-Temp 80 Recovery Systems. (For hot water supply appli

5858585858CHECKING HONEYWELL S-8600H OR S-8610MINTERMITTENT IGNITION CONTROLSTurn off gas supply.Is voltage (24 Vac) across the 24 V terminalson modul

5959595959CHECKING HONEYWELL S8600H OR S-8610MINTERMITTENT IGNITION CONTROLSSPARK AT PILOT BURNER BUT PILOT WILL NOT LIGHTEnsure all manual shutoff va

66666Where an exhaust fan is installed in the same room with a boiler,sufficient openings for air must be provided in the walls.UNDERSIZED OPENINGS WI

6060606060CHECKING HONEYWELL S-8600H OR S8610M INTERMITTENT IGNITION CONTROLSPILOT BURNER LIGHTS BUT MAIN BURNER DOES NOT LIGHTDoes the pilot flame c

6161616161CHECKING HONEYWELL S8600H OR S-8610MINTERMITTENT IGNITION CONTROLSNO SPARK AT PILOT BURNER BUT PILOT WILL NOT LIGHTTurn off gas supply.Is th

6262626262LIMITED WARRANTYA. O. Smith Corporation, the warrantor, extends the following LIMITED WARRANTY to the owner of this hydronic boiler.1. If wi

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64646464645621 W. 115TH STREET, ALSIP, IL 60803PHONE: 1-800-433-2545 FAX: 1-800-433-2515E-MAIL: [email protected] • www.hotwater.comREPLACEMENT P

777771. CONVENTIONAL INSTALLATIONSAll modern hydronic type boilers are exceptionally fast heating units.The low water volumes in relation to firing ra

88888NO. SUGGESTED ITEMS FOR INSTALLATION1 Short pipe nipple and pair of boiler loop tees in pipingbetween system supply and return. One set per e

99999Excessive pressure may develop causing premature tank failureor intermittent relief valve operation. This is not a warranty failure.An expansion