Raypak NH, 0133-4001 WH Troubleshooting Pumps, Service and Maintenance Procedures, Tube Cleaning

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TROUBLESHOOTING - PUMPS

FAILURE TO PUMP

1.Pump not properly primed.

2.Wrong direction of rotation.

3.Speed too low.

4.Total head too high.

REDUCED CAPACITY AND/OR HEAD

1.Air pockets or leaks in suction line.

2.Clogged impeller.

3.Foot valve strainer too small or clogged.

4.Excessive suction lift (over 15 feet).

5.Insufficient positive suction head (for hot water).

6.Total head more than that for which pump is intended.

7.Excessively worn impeller and wearing rings.

RAPIDWEAR OF COUPLING

1.Misalignment or a bent shaft.

2.Sagging motor mounts (over-oiling).

PUMP LOSES PRIME

1.Air leaks in suction line.

2.Excess air in water.

3.Water seal in stuffing box not functioning.

4.Excessive suction lift and pump operating too near shut-off point.

OVERLOADED DRIVING UNIT

1.Head much lower than that for which pump is designed.

2.Speed too high or higher than that contem- plated.

MECHANICAL TROUBLES AND NOISE

1.Misalignment.

2.Excessive suction lift or vapor binding (hot water).

3.Bent shaft and/or damaged bearings.

4.Suction and discharge piping not properly supported and anchored.

SERVICE AND MAINTENANCE PROCEDURES

Fig. # 8154

RAYPAK TUBE CLEANING KIT

Extension Pieces (5)

Auger with Carbide Tip

Wire Brush

 

 

 

TUBE CLEANING

Establish a regular inspection schedule, the frequency depending on the local water condition and severity of service. Do not let the tubes clog up solidly. Clean out deposits over 1/16" in thickness.

The heater may be cleaned from the side opposite the water connections as shown, without breaking pipe connections. It is preferable, however, to remove both

headers for better visibility through the tubes and to be sure the residue does not get into the system.

Note that you do not remove the top pan or the heat exchanger generally.

After reaming with the auger, mount the wire brush and clean out the debris remaining in the tubes.

Another method is to remove the heat exchanger, ream tubes and immerse heat exchanger in non- inhibited de-scale solvent.

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Contents Installation Operating Instructions For Your SafetyTable of Contents General Specifications Receiving Equipment ALL Models ApprovedModel Identification HOT Water Supply HeatersGeneral Safety Precautions Installation Instructions Installation CodesClearances Specifications and Dimensions ModelModels Models Outdoor Water Heaters High Wind Conditions Outdoor Units OnlyOutdoor Installations VentingIndoor Installations Before After Installation DrafthoodVent TERMINAL/INDOOR Stack Installation Vent Piping Fig. #7043.1Vent Damper Installation Models 133 Through 261 Where Required LocationVent Damper Plumbing GeneralGAS Supply Connections GAS Pressure Regulator Venting of Diaphragm GAS ComponentsFlow Rates General Specifications UNI-TEMP 80 HOT Water Supply Systems Piping Domestic HOT Water Supply HeatersPiping Diagrams Type WH Unitemp 80 System Type NH Instantaneous Minimum Input Adjustment Type NH Dual ModelsControls General Relief ValveElectronic Ignition Economaster ControlFlow Switch 100% Pilot SafetyHigh and LOW GAS Pressure Switches Optional Limit Controls High LimitComponent Identification Electrical Connections SINGLE-STAGE TankstatON/OFF Units 400 WH1, WH2, WH3 LOW NOx WH1 Location of ControlsFig. #9334 START-UP Procedures Before START-UP Initial START-UP Pump and MotorTIME/TEMPERATURE Relationships in Scalds ScaldingFor Your Safety Read Before Operating Operating InstructionsTo Turn OFF GAS to Appliance For Models with Manual GAS ValvesInspection Procedures Burners After START-UPControls For Models with Automatic GAS ValvesInspection Procedures Burner Adjustment High GAS Pressure SwitchSTART-UP Procedures Visual InspectionBurner Tray Removal Pilot RemovalGAS Valve Removal Main Burner and Orifice RemovalTroubleshooting Electrical Honeywell S8600Wiring Diagrams Wiring Diagram WH2 182/260 Wiring Diagram WH2 330/400 Wiring Diagram WH2 514/624 Wiring Diagram WH2 Wiring Diagram WH2 Wiring Diagram WH2 Wiring Diagram WH2 Wiring Diagram WH1 181/261 LOW NOx Wiring Diagram WH1 331/401 LOW NOx Troubleshooting Mechanical Problem Possible Cause Corrective ActionTroubleshooting Pumps Service and Maintenance ProceduresTube Cleaning Pilot Removal and Cleaning High Limit or Tankstat RemovalHeat Exchanger Removal Typical Burner Tray IllustratedHeat Exchanger RE-ASSEMBLY Control Well ReplacementTube Replacement Cleaning Flue GAS Passageways Replacement PartsCatalog Model Number Warranty Scope