A.O. Smith HW 610 warranty GAS Connections

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5. VENT VALVES

It is recommended that automatic, loose key or screwdriver type vent valves be installed at each convector or radiator.

6. MANIFOLD HEADERS

Split systems with individual supply and return lines from the boiler room should normally have this piping connected to supply and return manifold headers near the boiler. To achieve good water distribution with maximum pressure drop for several circuits, manifolds of at least 2-1/2" (64mm) diameter are suggested on HW-399, HW-420, HW-520, HW-610 and HW-670 units. HW-300 units should have 1-1/2" (38mm) diameter manifolds.

The circuits should be spaced on the header at a minimum of 3" (76mm) center to center. Install a balancing cock in each return line.

Manifold headers are recommended for split systems with or without zone valves and also those installations with zone circulators. If the system is to be split at remote points, good practice requires special attention be given to main pipe sizing to allow balancing of water flow.

The boiler piping system of a hot water boiler connected to heating coils located in air handling units where they may be exposed to refrigerated air circulation must be equipped with flow control valves or other automatic means to prevent gravity circulation of the boiler water during the cooling cycle.

7. COOLING PIPING

When the boiler is used in conjunction with a refrigeration system it must be installed so that the chilled medium is piped in parallel with the boiler with appropriate valves to prevent the chilled medium from entering the boiler, see Figure 13.

Water temperature in the heating system must be reduced to less than 1000F (38°C) before cooling system is started, or damage to the chiller unit may occur.

SCHEMATIC SHOWING PROPER PIPING ISOLATION

OF THE BOILER FROM THE CHILLER

FIGURE 13.

If the boiler is connected to chilled water piping or its heating coils are exposed to refrigerated air, the boiler piping system must be equipped with flow valves or other automatic means to prevent gravity circulation through the boiler during the cooling cycle.

8. CIRCULATING PUMP

CONSTANT CIRCULATING PUMP OPERATION OF THE BOILER VOIDS THE WARRANTY. Constant water flow through the unit will “wash” away the copper’s natural protective coating. This is called velocity erosion. This erosion is not as great a problem when intermittent circulating operation is used per the recommended installation procedure. Constant circulation of water through the building’s system main is permissible as long as the water does not constantly flow through the boiler. Only all bronze or stainless steel circulators are to be used with the unit when it is installed in HOT WATER SUPPLY SYSTEMS.

A TYPICAL CIRCULATING PUMP

FIGURE 14.

Although each circulator that requires oiling is oiled and operated by the manufacturer, IT MUST BE OILED AGAIN BEFORE OPERATED. Oil the three oil cups (2 on the motor, 1 on the pump) as instructed on the oil tube supplied with the unit, see Figure 14 on this page.

Thereafter, during the heating season, lubricate the three oil cups at least once every four months. Combination heating-cooling systems should be lubricated every four months year ‘round.

Use 2 or 3 teaspoonsful in bearing oil cups or 12 drops in the motor oil cups, see Figure 14 on this page. Use No. 20 non-detergent motor oil.

Follow the same oiling procedure if a replacement circulator is installed into the system.

GAS CONNECTIONS

WARNING

WHEN LOCAL CODES REQUIRE A MAIN MANUAL SHUTOFF

VALVE OUTSIDE THE BOILER JACKET, A SUITABLE MAIN

THIS BOILER IS NOT INTENDED TO OPERATE AT GAS SUPPLY

MANUAL SHUTOFF VALVE MUST BE INSTALLED IN A LOCATION

PRESSURE OTHER THAN SHOWN ON THE RATING PLATE.

COMPLYING WITH THOSE CODES.

EXPOSURE TO HIGHER GAS SUPPLY PRESSURE MAY CAUSE

 

DAMAGE TO GAS VALVES WHICH CAN RESULT IN FIRE OR

IT IS IMPORTANT TO GUARD AGAINST GAS VALVE FOULING

EXPLOSION. IF OVERPRESSURE HAS OCCURRED SUCH AS

FROM CONTAMINANTS IN THE GAS WAYS. SUCH FOULING

THROUGH IMPROPER TESTING OF GAS LINES OR EMERGENCY

MAY CAUSE IMPROPER OPERATION, FIRE OR EXPLOSION.

MALFUNCTIONOFTHESUPPLYSYSTEM,THEGASVALVESMUSTBE

 

CHECKEDFORSAFEOPERATION. MAKESURETHATTHEOUTSIDE

IF COPPER SUPPLY LINES ARE USED THEY MUST BE

VENTS ON THE SUPPLY REGULATORS AND THE SAFETY VENT

CERTIFIED FOR GAS SERVICE.

VALVESAREPROTECTEDAGAINSTBLOCKAGE. THESEAREPARTS

 

OFTHE GAS SUPPLYSYSTEM, NOTTHE BOILER. VENTBLOCKAGE

BEFORE ATTACHING THE GAS LINE BE SURE THAT ALL GAS

MAY OCCUR DURING ICE BUILD-UP OR SNOW STORMS.

PIPE IS CLEAN ON THE INSIDE.

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Contents Models HW 300, 399, 420, 520, 610 Tennessee Waltz Parkway Ashland City, TNSafe INSTALLATION, USE and Service Important DefinitionsGeneral Safety Table of Contents Dimensions and Capacity Data Propane NaturalRecovery Capacities 27.7 33.3LIQUefied petroleum gas models High Altitude InstallationsIntroduction Controls and Function Manual Reset High Limit High Limit Switch Safety Flow SwitchThermal Balancer GPM LPMSafety Relief Valves Tank Temperature Control General ThermometersDrain Valve Not Supplied Required AbilityConfined Space S. Installations Canadian InstallationsAIR Requirements Unconfined SpaceInstallation Clearances Typical Boiler InstallationVenting LevelingVent Pipe Installation Connecting Boiler to a Common VentDraft Hood Vent ConnectionVenting System Venting Sidewall Optional Power Vent SystemMultiple Vent Table Combined Vent Sizing Tables Model HW-300 BoilerSystem Installations Conventional InstallationsLINEAR-TEMP Installations ONE Boiler Installed Independent of the Primary SystemNO. Suggested Items for Installation Schematic of the LINEAR-TEMPSYSTEMBoiler Inlet Outlet Sizes Minimum Branch Sizes to BoilersGAS Connections Purging and Sizing Correct GASExample Specific Multiplier GravityGAS Pressure Regulators Model Rated Manifold Pressure Number Input Natural PropaneWiring Wiring ConnectionsHW 300 to D. SystemSingle Stage I.I.D. Honeywell GAS Valve HW 300 thru 670. Natural and Propane GAS U.S. & CanadaLINEAR-TEMP Installations Boilers and Secondary Circulator are Controlled by Page Canadian MODELS, Junction BOX W/6 Terminals MODELS, Jucntion BOX W/4 TerminalsCanadian MODELS, Junction BOX W/6 Terminals Schematic MODELS, Junction BOX W/4 Terminals MODELS, Junction BOX W/4 Terminals Wiring Figures 16 and 17 on Pages 24 PipingCommercial Boiler with Vertical Tank USE this Table for Correct Pump and Water Pipe SizeCommercial Boiler with Horizontal Tank Wiring Figures 21 to 27 on Pages 28 to Commercial Boiler with Vertical TANK, CER-TEMPHW-300 HW-399 HW-420 HW-520 Three HW-520s, HW-610s or HW-670s UP-FLOW Model USE this Table for Correct Pump and Water Pipe Size Operation and START-UP Instructions Filling the SystemPilot and Main Burner Main BurnerPilot Burner Electronic Ignition Refer to Operating at Full Input or Full Capacity Checking and Adjusting the InputConsumption Rate Stage Main Burner Operation Flame Current Sensed For Your Safety Read Before Lighting SET T HE Thermostat to Lowwest Setting URN Pilo T Firing VA LVE CounterclockwiseRelief Valve General MaintenanceManual Reset High Limit Switch Continuity Test Cleaning and Flushing Instructions PRE-TROUBLESHOOTINGHOT Water Supply Boilers Preventive Maintenance Internal ContaminantsTroubleshooting CER-TEMP 80 Recovery System Checkout ProcedureYES Burner ignition problems? Is ceramic insulator surrounding the electrode in goodCondition not cracked or broken? Is there excessive draft conditions that may cause pilotMV & MV/PV? Replace pilot burner assembly LED Status and Troubleshooting Location of LEDs Flame LED YellowStatus LED Green OFFNo Call for Heat Not applicable None OFF Limited Warranty Conditions and Exceptions
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