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.

Rapid Wear 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 contemplated.

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 support- ed and anchored.

SERVICE AND

MAINTENANCE

PROCEDURES

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 remain- ing in the tubes. Another method is to remove the heat exchanger, ream tubes and immerse heat exchanger in noninhibited de-scale solvent.

 

RAYPAK TUBE CLEANING KIT

 

 

Extension Pieces (5)

Auger with Carbide Tip

Wire Brush

P/N 052871F - 5/8 DIA.

P/N 052870F - 7/8 DIA.

 

 

 

 

 

Fig. 37: Raypak Tube Cleaning Procedure

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Raypak 1334001 operating instructions Service Maintenance Procedures, Troubleshooting-Pumps, Tube Cleaning