WGO, WTGO and SGO-WSeries 3 Oil-Fired Water BoilersOil-FiredWaterMaintenanceand ServiceGuideFor future rrefereference, leave this manualfutureeference,with other boiler instructionsin the envelope provided with the boilerprovidedboiler.Part No. 550-141-828/1202
Read This Page FirstHazard DefinitionsFollowing terms are used to bring attention to the presence of hazards of various risk levels, orto important information concerning product life.Indicates presence of hazards that will cause severe personal injury, death orsubstantial property damage if ignored.Indicates presence of hazards that can cause severe personal injury, death orsubstantial property damage if ignored.Indicates presence of hazards that will or can cause minor personal injury orproperty damage if ignored.Indicates special instructions on installation, operation, or maintenance thatare important but not related to personal injury hazards.Symbol DefinitionsThese symbols indicate information for and procedures to be followed by:Homeowner or person responsible for simple start-up and routinemaintenance of boiler and system. Pages 2 through 6 must be followedto assure proper operation of your boiler. Page 7 lists common problemsand possible corrections. In addition, it is your responsibility to: Have boiler and burner installed by a qualified installer. Have boiler and burner serviced annually by a qualified servicetechnician. Review and understand start-up and routine maintenanceprocedures with qualified service technician. Perform routine maintenance as described on page 4.Qualified service technician who has the necessary equipment tocheck the boiler and system performance, and is responsible forstart-up and service of boiler and system. Pages 2 and 3 and 8through 11 must be followed to assure proper operation of this boiler.In addition, it is the responsibility of this person to: 2Annually service boiler and burner to assure proper operation. See page 8for service record.Review and explain start-up and routine maintenance procedures withhomeowner.
For Your SafetyDANGERFollow instructions below toprevent severe personal injury, death or substantial property damage: Do not use crankcase drainings or any oilcontaining gasoline. See burner manual forproper fuel oil. Do not attempt to start burner when excessoil has accumulated in combustion chamber,when unit is full of vapor, or when combustion chamber is very hot. Do not start burner unless collector hood, fluecap, jacket cap, breeching and burner mounting door are secured in place. Never burn garbage or paper in the boiler. Never leave combustible material aroundboiler. DO NOT TAMPER WITH UNIT OR CONTROLS.Always follow specific instructions whenstarting up boiler or performing routinemaintenance or service.Tips for water systems: CAUTIONFailure to maintain recommended pH and repair leaks can cause sectioniron corrosion, leading to section failure andleaks. Do not use petroleum-based sealingor stop-leak compounds in boiler systems.Damage to system components can result,causing property damage. Boiler water pH 7.0 to 8.5 is recommended.For pH conditions outside 7.0 to 8.5 range orunusually hard water areas (above 7 grainshardness), consult local water treatmentcompany. When using antifreeze:- Use antifreeze especially made forhydronic systems. Inhibited propyleneglycol is recommended.WARNINGFollow instructions below toprevent severe personal injury, death or substantial property damage: To avoid electric shock, disconnect electricalsupply to burner service switch and additionalexternal switches before performing service. To avoid severe burns, allow boiler to coolbefore performing service. Do not block flow of combustion or ventilationair to boiler. Boiler must be connected to a flue withsufficient draft at all times to assure properoperation.Do not use this boiler if any part has beenunder water. Electrical and mechanicalfailures may cause electric shock and firerisks. Immediately call a qualified servicetechnician to inspect chimney or vent,boiler and burner. Have the boiler fluewayscleaned and have the following replaced:— all electrical and mechanical controls— electrical wiring— oil burner and controls— insulation and chamber liningCheck boiler and system piping for leaks.Continual makeup water will reduce boilerlife. Minerals can build up in sections,reducing heat transfer and causing cast ironto overheat, resulting in section failure.Do not use automotive,ethylene glycol, undiluted or petroleumbased antifreeze. Severe personal injury,death or substantial property damage canresult.--- 50% solution provides protection to about-300F.Local codes may require back-flowpreventer or actual disconnect from citywater supply.Determine quantity according to systemwater content. Boiler water content islisted on back cover of Boiler Manual.Percent of solution will affect sizing ofheat distribution units, circulator andexpansion tank.Follow antifreeze manufacturer's instructions.Do not add cold water to hot boiler. Thermalshock can cause sections to crack.3
Routine Maintenance ScheduleThe schedule below is specifically designed for the homeowner.Please read pages 2 and 3 before proceeding.Beginning each heating season:4 Call a qualified service technician to performannual service.End of heating season:4 If tankless heater is installed, boiler willcontinue to operate. Check for the following:Daily during heating season:-All daily and weekly instructions listed onthis page must be followed.-Burner motor may have to be oiled. Somemotors are permanently lubricated and donot need additional oil. Check for oilinginstructions on burner or motor.4 Check that boiler area is free from combustible materials, gasoline and other flammablevapors and liquids.Weekly during heating season:4 Check for and remove any obstructions to flowof combustion or ventilation air to boiler.4 Check that breeching is attached betweenboiler and chimney. If breeching is loose ordamaged, immediately turn off switch onboiler and call service technician to repair.4 Check for oil leaks in oil piping and aroundburner. If found, immediately call qualifiedservice technician to correct situation.4 Check for water leaks in boiler and piping;also check for leaks around tankless heaterplate, if installed. If found, immediately callservice technician to repair.4Boiler shutdown:Do not drain boiler unless exposure tofreezing temperatures will occur.Always keep manual fuel supply shut off ifburner is shut down for an extended period oftime.a. Turn off switch at boiler and any externalswitch to boiler.b. Close fuel valves.c. Turn off water feed valve.d. Cover burner to protect from dust anddampness.
Start-upWGO/WTGO (see Figure 1):1. If burner does not fire, check for:Service switch on boiler or additionalswitches turned off.Fuses or breaker switch tripped.Thermostat set below room temperature.Fuel valves turned off.Not enough oil in tank to supply burner.2. Correct problems found in step #1. If burnerdoes not fire, press reset button on burnerprimary control only once. Repeated presseswill deposit oil in combustion chamber.DANGERBurner must never be firedwhen oil is in combustion chamber. Immediately call qualified service technician.3. If burner still does not fire, call qualifiedservice technician.Temperature Pressure GaugeCirculatorLimit Control(on WGO)WaterRelief ValveCombinationLimit Control andTankless HeaterControl(on WTGO)Located in tanklessheater plateServiceSwitch onBoilerReset Button onBurner PrimaryControlBurnerDisconnectPlugBurner PrimaryControlWGO and WTGO BoilersFigure 15
Start-upSGO-W (see Figure 2):1. If burner does not fire, check for: Service switch on boiler or additionalswitches turned off. Fuses or breaker switch tripped. Thermostat set below room temperature. Fuel valves turned off. Not enough oil in tank to supply burner.2. Correct problems found in step #1. If burnerdoes not fire, press reset button on burnerprimary control only once. Repeated presseswill deposit oil in combustion chamber.DANGERBurner must never be firedwhen oil is in combustion chamber. Immediately call qualified service technician.3. If burner still does not fire, call qualifiedservice technician.nWater Relief Valve(on back of boiler)CirculatorTemperature Pressure GaugeLimit ControlTankless HeaterControlLocated intankless heater plateServiceSwitchon BoilerReset Button onBurner PrimaryControlBurnerDisconnectPlug6Burner PrimaryControlSGO-W BoilerFigure 2
COMMON PROBLEMSCOMMON CAUSESRapid cycling - burner turns on and offfrequently.Thermostat installed wheredrafts or heat affect reading.Locate thermostat on inner wall awayfrom heat sources or cool drafts.Heat anticipator inthermostat adjustedincorrectly.Adjust heat anticipator to match currentdraw. Refer to boiler wiring diagram.Incorrect limit setting.Have qualified service technicianincrease limit setting to decrease cycling.Maximum setting 220 deg. F.Need to frequently add makeup water.Leaks in boiler or piping.Have qualified service technician repairleaks at once to avoid constant use ofmakeup water.Popping or percolating noise heard in boiler.Mineral deposits in sectionsdue to constant use ofmakeup water, or incorrectpH.Have qualified service technician de-limeboiler, repair leaks at once to avoidconstant use of makeup water and checkpH (between 7.0 and 8.5).Black water condition.Oxygen corrosion due toleaks in piping.Have qualified service technician repairleaks at once to avoid constant use ofmakeup water and check pH (between7.0 and 8.5).Frequent release of water through reliefvalve.Expansion tank sized toosmall or water-logged.Have qualified service technician checkexpansion tank operation.Metal flakes found in flueway.Contaminated combustionair supply.Remove sources of hydrocarbons in ornear boiler area. (Bleaches, cleaners,chemicals, sprays, fabric softeners, paintremover, etc.)Condensation ofcombustion gases.Have qualified service technician checkboiler operation.Air in system.Bleed air from system through air ventsin radiators or baseboard units.Low system pressure.Have qualified service technician checkfor leaks in boiler or piping at once.High limit set too low.Have qualified service technican adjustlimit to higher setting.Mineral deposits insulateinternal waterways ofheater.Have qualified service technician delimeor replace coil.Boiler stop-leak compoundhas been added to boilerwater and is insulatingoutside of coil.Have qualified service technician removeand clean coil AND drain and flushboiler to remove stop-leak.Incorrect mixing valvesetting for tankless heater.Have quaified service technican adjustmixing valve setting.Domestic flow rate too high.Have qualified service technician installflow check valve set to rating of tanklessheater.Incorrect setting on tanklessheater control.Have qualified service technician raisetankless control setting. Adjustdifferential on tankless control to lowersetting.Some radiators or baseboard units do notheat or are noisy.Domestic water from tankless heater is hotthen suddenly turns cold.ORDomestic water from tankless heater isalways lukewarm.POSSIBLE CORRECTIONSThe problems and corrections above represent common situations that can occur.There may be others not listed above. It is important always to contact a qualified service technician if you have any questions about the operation of your boiler or system.7
Annual Service Check ListThe procedures and information on pages 7 through 11 areintended only for a qualified service technician who has the necessaryequipment to inspect and adjust boiler and burner. A homeowner shouldnever attempt these procedures. Qualified service technician must readpages 2 and 3 before proceeding.Annual Service Call Check List(follow in order listed ents1 Check that boiler area is free fromcombustible materials, gasoline and otherflammable vapors and liquids.2 Check for and remove any obstruction tocombustion and ventilation air flow to boiler.3 Check breeching and chimney or vent forobstructions, damage, etc. Repair or replaceas necessary.4 Clean boiler flueways. See page 9.5 Perform service on relief valve and circulator.See page 11.6 Check boiler and piping for leaks and repair iffound. Check for leaks at tankless heaterplate. Tighten nuts only if leaks are found (forWTGO torque to 20-25 ft.lbs.).7 Inspect and adjust burner. See burner manualand:- change nozzle.- check ignition electrode settings.- clean blower housing and wheel.- make sure blower wheel turns freely.- oil burner motor if required.- clean air inlet.- clean or change fuel filter and strainer.8 Make sure boiler is filled with water.9 Start unit and verify combustion settings withcombustion test equipment.See page 10.10 Verify operation of all controls on boiler. Seepage 11.8Any parts of the boiler furnished by Weil-McLain must be replaced by parts listed inWeil-McLain Boiler and Repair Parts Book.
Detailed Service ProceduresCleaning boiler flueways:DANGERMake sure all electrical connectionsto boiler are turned off and wait until boiler iswarm, not hot, before cleaning. Failure to do sowill result in severe personal injury, death orsubstantial property damage.1. Top flue boilers -remove breeching and jackettop panel.Rear flue boilers - remove jacket top panel.2. Remove flue collector hood, saving hardwarefor reassembly.3. Shut off oil valves. Arrange drip pans underthe areas of oil piping that will be disconnected. Disconnect oil line at burner so thatyou can swing open the door completely.4. Line combustion chamber floor with newspaper to catch any soot that will be loosenedin the cleaning process.5. Starting at the top of the boiler, use a wireflue brush to thoroughly clean between allpins at all angles. Be careful not to damageside walls of rear refractory.6. Move to the bottom of the flueways and cleanup between the sections to reach pins leftuncleaned in step #5.7. Once the flueways are cleaned, carefullyremove the paper from the floor of thecombustion chamber.8. Verify sealing rope around flue area is intact.Visually check condition and position ofinsulation in combustion chamber floor,and the refractories at the rear of boiler andin the burner mounting door. Replace anyparts as necessary.9. Close burner mounting door and tighten nutsecurely. Place flue collector hood on top ofboiler. Secure with hardware from step #2.Maintain a gas-tight seal toavoid possible flue gas leakage and carbonmonoxide emissions, which can lead to severepersonal injury or death.10. Check breeching for sooting and clean ifnecessary. Install jacket top panel andbreeching.11. Reconnect oil line and all electrical connections.Thoroughly clean fluewaysbetween all pins at all angles.Start on top of boiler,finish from the bottom.Cleaning Boiler FluewaysFigure 39
Detailed Service ProceduresFill the system:To place in operation:1. Close manual and automatic air vents anddrain cock.2. Fill to correct system pressure. Correct pressure will vary with each installation. Normalcold water fill pressure for residential systemsis 12 psig. Boiler water pH 7.0 to 8.5 is recommended.DANGERFollow information below to preventsevere personal injury, death or substantial property damage: Do not use crankcase drainings or any oilcontaining gasoline. See burner manual forproper fuel oil. Do not attempt to start burner when excess oilhas accumulated in combustion chamber,when unit is full of vapor, or when combustion chamber is very hot. Do not start burner unless collector hood, fluecap, jacket cap, breeching and burner mounting door are secured in place. Never burn garbage or paper in the boiler.Never leave combustible material aroundboiler.NOTICEFailure to maintain recommended pH level can cause section failure andleaks.3. Open automatic air vent one turn.4. a. Starting on the lowest floor, open air ventsone at a time until water squirts out. Closevent.b. Repeat with remaining vents.5. Refill to correct pressure.1. Verify boiler is filled with water.2. Open burner door and verify rear target wall,floor and burner door insulations are inproper condition and position.3. Verify burner mounting door is closed andbolted tightly and burner plug is connected.4. Refer to burner manual for burner start-up,adjustment and check-out procedures.Factory burner adjustment and settings maynot be suitable for specific job conditions.Make final burner adjustmentsusing combustion test equipment to assureproper operation. Do not fire boiler withoutwater. Sections will overheat, damaging boilerand resulting in substantial property damage.5. Check boiler and system piping for leaks.6. Inspect breeching and venting for properoperation.10
Detailed Service ProceduresControls requiring annual service:WATER RELIEF VALVE:CIRCULATOR:Check operation of water relief valve. Followinstructions on label fastened to relief valve.Follow oil-lubricating instructions on circulator.Over-oiling will damage circulator.Water-lubricated circulators do not need oiling.DANGERScald potential. Do not checkoperation of relief valve unless discharge pipinghas been installed according to Boiler Manual.If piping is not in place, a qualified service technician must properly install piping.General description of control operation:TANKLESS WATER HEATER:AUTOMATIC AIR VENT:Weil-McLain tankless heater ratings are based on2000F boiler water temperature. To get rated output, set tankless heater control to 2000F. Controlcan be adjusted to meet system hot water requirements.Air is released when cap is unscrewed one turn.If air vent leaks, remove small cap on top of vent,push in stem of valve and then release to cleanvalve seat. Screw cap completely on, then unscrewone turn.WATER RELIEF VALVE:Provides discharge if boiler pressure exceeds 30psig.EXPANSION TANK:As water heats up, it expands. Tank provides aplace for increased water volume. May be open,closed, or diaphragm-type. If relief valve opensfrequently, expansion tank may be water-logged.Drain tank and re-establish proper air cushion.TEMPERATURE LIMIT CONTROL:1. Open-type - Located above highest radiator orbaseboard unit, usually in the attic or closet.Has a gauge glass and overflow pipe to drain.If high boiler water temperature occurs, controlshuts down burner, but allows circulator to runas long as there is a call for heat. Limit should beset higher than temperature needed for the system. Maximum limit setting is 2200F.2. Closed-type - Welded gas tight and locatedabove boiler. Tank is partially filled withwater, leaving an air cushion for expansion.CIRCULATOR:Circulator provides forced water circulationthrough boiler and piping system.PRESSURE-TEMPERATURE GAUGE:Provides reading of boiler pressure and temperature. Maximum boiler pressure is 50 psig, maximum water temperature is 2200F. Temperaturewill vary according to system and daily heating demands. The range will be from room temperatureup to limit control setting.3. Diaphragm-type - Welded gas tight with arubber diaphragm to separate air from water.Tank must be located near boiler before inletto circulator.An air vent must be installed in air venttapping on boiler when this type of tank isused. This eliminates air in system.Normal cold water fill pressure is 12 psig.Tank pressure may be checked with an airpressure gauge.11
12.Part No. 550-141-828/1202
Not enough oil in tank to supply burner. DANGER WGO and WTGO Boilers Figure 1. 2. Correct problems found in step #1. If burner does not fire, press reset button on burner primary control only once. Repeated presses will deposit oil in combustion chamber. Burner must never be fired when oil