A.O. Smith COF-199 manual Combustion Test Specifications, Normal START, but Locks OUT on Safety

Page 22

If the problem is not getting a spark to ignite the oil, check for the following:

1.Loose wiring.

2.Bad ignition transformer.

3.Low voltage.

4.Crack in electrode porcelain insulators.

5.Electrodes carboned or out of adjustment.

6.Weak or no contact between bus bars and terminals of transformer.

NORMAL START, BUT LOCKS OUT ON SAFETY

When the thermostat calls for heat and the burner starts normally but the locks out on safety after about 15 seconds:

1.Improper setting of combustion air (too much air).

2.Weak or dirty flame detector.

3.Improper positioning of flame detector.

4.Bad flame detector.

5.Wiring from flame detector to primary not continuous or not making good contact.

6.Bad safety primary control.

7.Clogged, defective or to small sized nozzle.

SAFETY PRIMARY CONTROL

Normal Burner Cycle

Although a normal burner cycle does not create a service problem, it is important to know what happens to better understand the problem when the unit is not operating properly.

The instant the thermostat calls for heat, the flame detector sees darkness and causes the sensor to conduct current. When the sensor conducts current, the motor relay coil pulls in, starting the burner motor and energizing the ignition transformer through the motor relay contacts. At the same instant the motor relay coil pulls in, the safety heater is energized.

When flame is established, the resistance of the flame detector drops (providing the flame detector can see the flame properly) which causes the sensor to block the current. When the sensor blocks, the safety heater drops out of the circuit and the motor relay coil continues to hold in through a set of holding contacts on the motor relay until the thermostat is satisfied and the burner shuts down.

FLAME FAILURE AFTER NORMAL IGNITION

If, for some reason, there is a flame out, the flame detector sees darkness which causes the sensor to conduct current and again energize the safety heater. In approximately 15 seconds the safety contact will open and shut down the burner. The safety contacts of the safety primary control are the manual reset type, which means that the red safety button must be reset before trying again for ignition. When this occurs, allow about 5 minutes for safety heater to cool before depressing the red safety button.

Depress red button one time only. If burner does not operate after depressing red button one time, check combustion chamber. If combustion chamber is soaked with oil the combustion chamber must be replaced.

Some of the possible reasons for flame failure after normal ignition has occurred are:

1.Dirt or water in the supply line.

2.Pump loosing prime.

3.Bad motor.

4.Erratic or low pressure at fuel pump.

5.Defective pump.

6.Loose wiring or connections.

7.Clogged or damaged nozzle.

8.Oil tank empty.

9.Oil tank not vented.

10.Clogged filter in oil line.

11.Ice in fuel line.

COMBUSTION TEST

SPECIFICATIONS

GENERAL

A combustion test kit, capable of testing CO2 content, stack temperature, draft and smoke must be available to aid in adjusting the unit and filling out the Oil Burner Certificate. A pressure gauge is needed to measure and adjust oil pump pressure.

PROCEDURE

1.Check nozzle size, see table on page 9.

2.Open air band about halfway and being certain heater is filled with water, start burner.

3.Check oil pump pressure. It should be 110 psig for the COF-199 and 110 psig for all other models. Adjust setting as necessary.

4.Allow burner to operate for 15 minutes before proceeding with test.

5.After 15 minutes operation, check the draft in chimney connector, about halfway between the heater and the draft regulator and adjust the draft regulator until the correct reading is obtained.

Draft in Chimney

.03 to .05

Connector

Inches of Water

 

 

6.Adjust air band until flame has smoky tips. Immediately increase air supply until the smoky tips just appear.

7.Using combustion test kit, check smoke density and CO2 in the chimney connector.

 

Preferably No. 1

Spot

Smoke Density

(Not Over No. 2 Spot

CO2

9% to 12%

 

 

 

 

Adjust air supply with air band to achieve the highest CO2 readings with an acceptable smoke density reading. Test and readjust as necessary.

8.Check the stack temperature halfway between the heater and the draft regulator.

Stack

Min.

400° F (204°C)

 

 

Temperature

 

 

Max.

600° F (315°C)

 

 

 

 

If stack temperature is too high, check for a soot accumulation in heater or excessive oil pump pressure.

9.Recheck combustion efficiency against specifications when final adjustments have been made.

22

Image 22
Contents Place These Instructions Adjacent to Heater Notify Owner to Keep for Future ReferenceTank Approx Features and SpecificationsCapacity EFF Table of Contents ApprovalsSafety InstallationCombustion and Ventilation AIR Proper Installation on Combustible FlooringClearances Chemical Vapor CorrosionVent Connector and Draft Regulator Flue GAS VentingClosed Water System Water PipingFuel Systems Gravity FEED, Supply Line ONLY, Installation Burner InstallationTypical Heater Installation Figure System TypesFuel Pump OIL Pump & Nozzle SpecificationsAssembly of the OIL Burner to the Heater BurnerFilling OperationSTART-UP SELF-CLEANING Eliminator Water Temperature ControlHigh Limit Switch E.C.O Burner Certificate Combustion TestMaintenance Flo-jug Method of Deliming Deliming the COF Water HeaterVent System Circulating PumpSoot Removal Typical Heater Flueway and Flue BaffleInset B Installation DiagramsInstall in Accordance with Local Codes Inset aSingle Temperature or Booster Pipe to Open DrainInset B Install in Accordance with Local Codes Inset a Electrical Wiring Replacement Check List and Service InformationNot Enough or no HOT Water Water Heater Makes Sounds Burner STARTS-WONT OperateWater is TOO HOT Water Leakage is SuspectedSafety Primary Control Combustion Test SpecificationsNormal START, but Locks OUT on Safety ProcedureOIL Burner Troubleshooting TroubleshootingTrouble Cause Remedy Tank Service and Repair ExpensesClaim Procedure ALL Other PartsCommercial Water Heater Parts List Smith Water Products CO., INC+WIRE Cleanout AssemblyLabels Page Page Asme Impriméaux É.-UPoids approx Lexpédition Dimensions COFCaractéristiques ET Données Techniques StandardIdentification Table DES MatièresHomologations COF 455 940 CO5MOO6721Installation SécuritéAIR DE Combustion ET DE Ventilation Installation Correcte SUR UN Plancher CombustibleDégagement À Prévoir Corrosion DUE AUX Vapeurs ChimiquesÉvacuation DES GAZ DE Combustion Tableau 4 Dimensions Suggérées Pour LES Raccords D’ÉVENTInstallation Appropriée DU Raccord D’ÉVENT Cheminée Raccord D’ÉVENT ET Régulateur DE TirageRobinet DE Vidange ET Panneaux D’ACCÈS Tuyauterie D’EAUSystème EN Circuit Fermé Systèmes D’ALIMENTATION EN CombustibleTableau Installation DU BrûleurInstallation Type DE CHAUFFE-EAU Figure Types DE SystèmesMontage DU Brûleur SUR LE CHAUFFE-EAU Pompe À MazoutBrûleur Tableau 8 Caractéristiques DES Pompes ET DES Buses À MazoutRemplissage Mise EN Marche ET UtilisationMise EN Marche Initiale Certificat DU Brûleur Test DE Combustion Réglage DE LA Température DE L’EAULimiteur DE Température Système Autonettoyant EliminatorEntretien Méthode de détartrage Flo-Jug Détartrage DU CHAUFFE-EAU COFEnlèvement DE LA Suie Pompe DE CirculationConduit DE Fumée ET Chicane D’UN CHAUFFE-EAU Type Encadré B Schémas D’INSTALLATIONInstaller Conformément AUX Codes Locaux Encadré aSystème À UNE Seule Température OU Surchauffeur Encadré B Installer Conformément AUX Codes Locaux Encadré B Insuffisance OU Absence D’EAU Chaude Liste DE Contrôle ET Renseignements SUR LE ServiceRemplacement DU Câblage Électrique Ensemble DE Collecteur Pour Trois AppareilsBruits EN Provenance DU CHAUFFE-EAU LE Brûleur Démarre Mais NE Fonctionne PASEAU Trop Chaude Fuite D’EAU SoupçonnéeDémarrage Normal Suivi ’UN Verrouillage DE Sécurité Commande Primaire DE SécuritéSpécifications Pour LE Test DE Combustion Perte DE LA Flamme Après UN Allumage NormalProblème Cause Mesure Corrective DépannageTableau 10 Dépannage DU Brûleur À Mazout Modèles COF Garantie Limitée Autres PiècesSmith Water Products CO., INC COF Article Description