PIPING COLOR CODES

Figures 12.1 through 12.27 provide useful tables to help you in troubleshoot­ing problems.

219

1. What well conditions might possibly limit the capacity of the pump?

2. How does the diameter of a cased deep well and pumping level of the water affect the capacity?

3. If there are no limiting factors, how is capacity determined?

4. What is suction?

The rate of flow from the source of supply, the diameter of a cased deep well, and the pumping level of the water in a cased deep well.

They limit the size pumping equipment which can be used.

By the maximum number of outlets or faucets likely to be in use at the same time.

A partial vacuum, created in the suction chamber of the pump, obtained by removing pressure due to atmosphere, thereby allowing greater pressure outside to force something (air, gas, water) into the container.

The atmosphere surrounding the earth presses against the earth and all objects on it, producing what we call atmospheric pressure.

This pressure varies with elevation or altitude. It is greatest at sea level (14.7 pounds per square inch) and gradually decreases as elevation above sea level is increased. The rate is approximately 1 foot per 100 feet of elevation.

Since suction lift is actually that height to which atmospheric pressure will force water into a vacuum, theoretically we can use the maximum amount of this pressure 14.7 pounds per square inch at sea level which will raise water 33.9 feet. From this, we obtain the conversion factor of 1 pound per square inch of pressure equals 2.31-feet head.

The resistance of the suction pipe walls to the flow of water uses up part of the work which can be done by atmospheric pressure. Therefore, the amount of loss due to friction in the suction pipe must be added to the vertical elevation which must be overcome, and the total of the two must not exceed 25 feet at sea level. This 25 feet must be reduced 1 foot for every 1000-feet elevation above sea level, which corrects for a lessened atmospheric pressure with increased elevation.

5. What is atmospheric pressure?

6. How much is the pressure due to atmosphere?

7. What is maximum theoretical suction lift?

8. How does friction loss affect suction conditions?

9. When and why do we use a deep — well jet pump?

The resistance of the suction pipe walls to below the pump because this is the maximum practical suction lift which can be obtained with a shallow-well pump at sea level.

A pump with all necessary accessories, fittings, etc., necessary for its completely automatic operation.

It is used on the end of a suction pipe to prevent the water in the system from running back into the source of supply when the pump isn’t operating.

10. What do we mean by water systems?

11. What is the purpose of a foot value?

12. Name the two basic parts of a jet assembly.

13. What is the function of the nozzle?

Nozzle and diffuser.

The nozzle converts the pressure of the driving water into velocity. The velocity thus created causes a vacuum in the jet assembly or suction chamber.

The diffuser converts the velocity from the nozzle back into pressure.

That water which is supplied under pressure to drive the jet.

The driving water is continuously recirculated in a closed system.

The centrifugal pump provides the energy to circulate the driving water. It also boosts the pressure of the discharged capacity.

Bolted to the casing of the centrifugal pump.

14. What is the purpose of the diffuser?

15. What do we mean by “driving water’?

16. What is the source of the driving water?

17. What is the purpose of the centrifugal pump?

18. Where is the jet assembly usually located in a shallow-well jet system?

19. What is the principal factor which determines if a shallow — well jet system can be used?

20. When is a deep-well jet system used?

21. Can a foot valve be omitted from a deep-well jet system? Why or why not?

Total suction lift.

When the total suction sift exceeds that which can be overcome by atmospheric pressure.

No, because there are no valves in the jet assembly, and the foot valve is necessary to hold water in the system when it is primed. Also, when the centrifugal pump isn’t running, the foot valve prevents the water from running back into the well.

FIGURE 12.1 ■ (Continued) Questions and answers about pumps. (Courtesy of McGraw-Hill)

22. What is the function of a check valve in the top of a submersible pump?

23. A submersible pump is made up of two basic parts. What are they?

24. Why did the name submersible pump come into being?

25. Can a submersible pump be installed in a 2-inch well?

To hold the pressure in the line when the pump isn’t running.

Pump end and motor.

Because the whole unit, pump and motor, is designed to be operated under water.

No, they require a 4-inch well or larger for most domestic use. Larger pumps with larger capacities require 6-inch wells or larger.

Impeller, diffuser, and bowl.

26. A stage in a submersible pump is made up of three parts. What are they?

27. Does a submersible pump have only one pipe connection?

28. What are two reasons we should always consider using a submersible first?

29. The amount of pressure a pump is capable of making is controlled by what?

30. What do the width of an impeller and guide vane control?

Yes, the discharge pipe.

It will pump more water at higher pressure with less horsepower. It also has easier installation.

The diameter of the impeller.

The amount of water or capacity the pump is capable of pumping.

Motor does not start

Checking procedure

Using voltmeter check the line terminals Voltage must be ± 10% of rated voltage.

Check fuses for recommended size and check for loose, dirty or corroded connections in fuse receptacle. Check for tripped circuit breaker.

Check voltage at contact points. Improper contact of switch points can cause voltage less than line voltage.

Check for loose or corroded connections. Check motor lead terminals with voltmeter for power.

Locked rotor conditions can result from misalignment between pump and motor or a sand bound pump. Amp readings 3 to 6 times higher than normal will be indicated.

Cause of trouble

A. No power or incorrect voltage.

Correction action

Contact power company if voltage is incorrect.

Replace with proper fuse or reset circuit breaker.

B. Fuses blown or circuit breakers tripped.

Replace pressure switch or clean points.

Repair or replace.

Correct faulty wiring or connections.

C. Defective pressure switch.

D. Control box malfunction.

E. Defective wiring.

If pump will not start with several trials it must be pulled and the cause corrected. New installations should always be run without turning off until water clears.

Repair or replace.

F, Bound pump.

Motor starts too often

Check setting on pressure switch and examine for defects.

Damaged or defective check valve will not hold pressure.

Check air charging system for proper operation.

Check system for leaks.

Reset limit or replace switch.

Replace if defective.

Clean or replace.

Replace damaged pipes or repair leaks.

Motor runs continuously

Checking procedure

Switch contacts may be “welded” in closed position. Pressure switch may be set too high.

Pump may exceed well capacity. Shut off pump, wait for well to recover. Check static and drawdown level from well head.

Check system for leaks.

Symptoms of worn pump are similar to those of drop pipe leak or low water level in well. Reduce pressure switch setting. If pump shuts off, worn parts may be at fault. Sand is usually present in tank.

No or little water will be delivered if coupling between motor and pump shaft is loose or if a jammed pump has caused the motor shaft to shear off.

Restricted flow may indicate a clogged intake screen on pump. Pump may be installed in mud or sand.

No water will be delivered if check valve is in closed position.

Cause of trouble A. Pressure switch.

Correction action

Clean contacts replace switch, or readjust setting.

Throttle pump output or reset pump to lower level. Do not lower if sand may clog pump.

Replace damaged pipes or repair leaks.

Pull pump and replace worn impellers, casing or other close fitting parts.

B. Low level well.

C. Leak in system.

D. Worn pump, motor shaft.

E. Loose or broken.

Check for damaged shafts if coupling is loose and replace worn or defective units.

Clean screen and reset at less depth. It may be necessary to clean well.

Replace if defective.

F. Pump screen blocked.

G. Check valve stuck closed.

H. Control box malfunction.

Repair or replace.

Motor runs but overload protector trips

Using voltmeter, check the line terminals. Voltage must be within ± 10% of rated voltage.

Direct sunlight or other heat source can make control box hot causing protectors to trip. The box must not be hot to touch.

Contact power company if voltage is incorrect.

A. Incorrect voltage.

B. Overheated protectors.

Shade box, provide ventilation or move box away from heat source.

C. Defective control box.

D. Defective motor or cable.

E. Worn pump or motor.

Repair or replace.

Repair or replace.

Replace pump and/or motor.

FIGURE 12.6 ■ Troubleshooting motors. (Courtesy of McGraw-Hill)

Measure resistance from any cable to ground (insulation resistance)

1. If the ohm value is normal, the motor windings are not grounded and the cable insulation is not damaged.

2, If the ohm value is below normal, either the windings are grounded or the cable insulation is damaged. Check the cable at the well seal as the insulation is sometimes damaged by being pinched.

1. If all ohm values are normal, the motor windings are neither shorted nor open, and the cable colors are correct.

2. If any one ohm value is less than normal, the motor is shorted.

3. If any one ohm value is greater than normal, the winding or the cable is open, or there is a poor cable joint or connection.

4. If some ohm values are greater than normal and some less on single phase motors, the leads are mixed.

Measure winding resistance (resistance between leads)

FIGURE 12.7 ■ Troubleshooting motors. (Courtesy of McGraw-Hill)

Normal ohm and megohm values between all leads and ground

Insulation resistance varies very little with rating. Motors of all hp, voltage, and phase rating have similar values of insulation resistance.

pump must be pulled and the cable repaired or the motor replaced.

FIGURE 12.8 ■ Resistance readings. (Courtesy of McGraw-Hill)

Meter connections for motor testing

Ground

pump

Ground

To check voltage

1. Turn power OFF

2. Remove QD cover to break all motor connections.

Caution: LI and L2 are still connected to the power supply.

3. Turn power ON,

4, Use voltmeter as shown.

FIGURE 12.10 ■ Meter connections for motor testing. (Courtesy of McGraw-Hill)

Amprobe meter

To check current (amps)

1. Turn power OFF

2. Connect test cord as shown.

3. Turn power ON

4. Use hook-on type ammeter as shown.

FIGURE 12.11 ■ Checking amperage. (Courtesy of McGraw-Hill)

Single-phase control boxes

Checking and repairing procedures (Power on)

Caution: Power must be on for these tests. Do not touch any live parts.

A. General procedures:

1. Establish line power.

2. Check no load voltage (pump not running).

3. Check load voltage (pump running).

4. Check current (amps) in all motor leads.

B. Use of volt/amp meter:

1. Meter such as Amprobe Model RS300 or equivalent may be used.

2. Select scale for voltage or amps depending on tests.

3. When using amp scales, select highest scale to allow for inrush current, then select for midrange reading.

C. Voltage measurements:

Step 1, no load.

1. Measure voltage at LI and L2 of pressure switch or line contractor.

2. Voltage Reading: Should be ± 10% of motor rating.

Step 2, load.

1. Measure voltage at load side of pressure switch or line contractor with pump running.

2. Voltage Reading: Should remain the same except for slight dip on starting.

D. Current (amp) measurements:

1. Measure current on all motor leads. Use 5 conductor test cord for Q. D. control boxes.

2. Amp Reading: Current in Red lead should momentarily be high, then drop within one second. This verifies relay or solid state relay operation.

E. Voltage symptoms:

1. Excessive voltage drop on starting.

2. Causes: Loose connections, bad contacts or ground faults, or inadequate power supply.

F. Current symptoms:

1. Relay or switch failures will cause Red lead current to remain high and overload tripping.

2. Open run capacitor(s) will cause amps to be higher than normal in the Black and Yellow motor leads and lower than normal or zero amps in the Red motor lead.

3. Relay chatter is caused by low voltage or ground faults.

4. A bound pump will cause locked rotor amps and overloading tripping.

5. Low amps may be caused by pump running at shutoff, worn pump or stripped splines.

6. Failed start capacitor or open switch/relay are indicated if the red lead current is not momentarily high at starting.

Single-phase control boxes

Checking and repairing procedures (Power off)

Caution: Turn power off at the power supply panel and discharge capacitors before using ohmmeter.

A. General procedures:

1. Disconnect line power.

2. Inspect for damaged or burned parts, loose connections, etc.

3. Check against diagram in control box for misconnections.

4. Check motor insulation and winding resistance.

B. Use of ohmmeter:

1. Ohmmeter such as Simpson Model 372 or 260. Triplet Model 630 or 666 may be used.

2. Whenever scales are changed, clip ohmmeter lead together and “zero balance” meter.

C. Ground (insulation resistance) test:

1. Ohmmeter Setting: Highest scale R x 10K, or R x 100K

2. Terminal Connections: One ohmmeter lead to “Ground” terminal or Q. D. control box lid and touch other lead to the other terminals on the terminal hoard.

3. Ohmmeter Reading: Pointer should remain at infinity (°°).

Additional tests

Solid state capacitor run (CRC) control box

A. Run capacitor

1. Meter setting: R X 1,000

2. Connections: Red and Black leads

3. Correct meter reading: Pointer should swing toward zero, then drift back to infinity.

B. Inductance coil

1. Meter setting: R X 1

2. Connections: Orange leads

3. Correct meter reading: Less than 1 ohm.

C. Solid state switch

Step 1 triac test

1. Meter setting: R X 1,000

2. Connections: R(Start) terminal and Orange lead on start switch.

3. Correct meter reading: Should be near infinity after swing.

Step 2 coil test

1. Meter setting: R x 1

2. Connections: Y(Common) and L2.

3. Correct meter reading: Zero ohms

Orange

Capacitor

Yellow

В (.main)

R (start) L2

V3-1 hp QD relay

Blue

Capacitor

Orange

Solid state start switch

Black

В (main) Y (comm) R (start) L2

VH hp QD

Start cap

capacitor

Black,

lV2hp

Orange

Yellow

LI L2 Yel Blk Red

4" standard 172 hp

FIGURE 12.14 ■ Wiring diagrams. (Courtesy of McGraw-Hill)

FIGURE 12.15 ■ (Continued) Data chart for single-phase motors. (Courtesy of McGraw-Hill)

Integral horsepower control box parts

QD control box parts

(1) Prefixes 152 are solid state switches. Prefixes 223 are QD (Blue) Relays.

(2) Control boxes supplied with solid state relays are designed to operate on normal 230 V systems. For 208 V systems or where line voltage is between 200 V use the next larger cable size, or use boost transformer to raise the voltage to 230 V.

(3) Voltage relay kits 115 V, 305 102 901 and 230 V. 305 102 902 will replace either current voltage or QD Relays, and solid state switches.

(4) QD control boxes produced H85 or later do not contain an overload in the capacitor. On winding thermal overloads were added to three-wire motors rated Vi-1 hp in A85. If a control box dated H85 or later is applied with a motor dated M84 or earlier, overload protection can be provided by adding an overload kit to the control box.

(5) May be replaced with QD relay kits 305 101 901 thru 906. Use same kit suffix as switch or relay suffix.

(6) Replace with CRC QD Relaying Kits, 223 415 912 with 305 105 901, 223 415 913 with 305 105 902 and 223 415 914 with 305 105 903.

FIGURE 12.17 ■ Data chart for single-phase motors. (Courtesy of McGraw-Hill)

Symptoms Probable cause

Won’t start No electrical power

Wrong voltage Bad pressure switch Bad electrical connection Bad motor

Motor contacts are open Motor shaft is seized

Runs, but produces no water Needs to be primed

Foot valve is above the water level in the well

Strainer clogged Suction leak

Starts and stops too often Leak in the piping

Bad pressure switch Bad air control valve Waterlogged pressure tank Leak in pressure tank

Low water pressure in pressure tank Strainer on foot valve is partially

blocked

Leak in piping

Bad air charger

Worn impeller hub

Lift demand is too much for the

pump

Pump does not cut off when working Pressure switch is bad

pressure is obtained Pressure switch needs adjusting

Blockage in the piping

FIGURE 12.18 ■ Troubleshooting jet pumps. (Courtesy of McGraw-Hill)

Symptoms Probable cause

Won’t start No electrical power

Wrong voltage Bad pressure switch Bad electrical connection

Starts, but shuts off fast Circuit breaker or fuse is inadequate

Wrong voltage

Bad control box

Bad electrical connections

Bad pressure switch

Pipe blockage

Pump is seized

Control box is too hot

Runs, but does not produce water, or Check valve stuck in closed position

produces only a small quantity Check valve installed backward

Bad electrical wiring Wrong voltage

Pump is sitting above the water in the well

Leak in the piping Bad pump or motor Broken pump shaft Clogged strainer Jammed impeller

Low water pressure in pressure tank Pressure switch needs adjusting

Bad pump Leak in piping Wrong voltage

Pump runs too often Check valve stuck open

Pressure tank is waterlogged and needs air ipjected Pressure switch needs adjusting Leak in piping Wrong-size pressure tank

FIGURE 12.19 ■ Troubleshooting submersible potable-water pumps. (Courtesy of McGraw-Hill)

Symptoms

Relief valve leaks slowly Relief valve blows off periodically

No hot water

Water not hot enough

Water too hot Water leaks from tank

Probable cause

Bad relief valve

High water temperature High pressure in tank Bad relief valve

Electrical power is off Elements are bad Defective thermostat Inlet valve is closed

An element is bad Bad thermostat Thermostat needs adjusting

Thermostat needs adjusting Controls are defective

Hole in tank

Rusted-out fitting in tank

FIGURE 12.20 ■ Troubleshooting electric water heaters. [Courtesy of McGraw-Hill)

Symptoms

Relief valve leaks slowly Relief valve blows off periodically

No hot water

Water not hot enough Water too hot

Water leaks from tank

Probable cause

Bad relief valve

High water temperature High pressure in tank Bad relief valve

Out of gas Pilot light is out Bad thermostat Control valve is off Gas valve closed

Bad thermostat Thermostat needs adjusting

Thermostat needs adjusting Controls are defective Burner will not shut off

Hole in tank

Rusted-out fitting in tank

FIGURE 12.21 ■ Troubleshooting gas water heaters. [Courtesy of McGraw-Hill)

Symptoms Will not flush

Flushes poorly

Water droplets covering tank Tank fills slowly

Makes unusual noises when flushed Water runs constantly

Water seeps from base of toilet Water dripping from tank

No water comes into the tank

FIGURE 12.23 ■ Troubleshooting toilets. (Courtesy of McGraw-Hill)

Symptoms Won’t drain

Drains slowly Gurgles as it drains Water drips from shower head Faucet will not shut off Poor water pressure

No water

Probable cause

Clogged drain Clogged strainer Clogged trap

Hair in strainer Partial drainage blockage

Partial drainage blockage Partial blockage in the vent

Bad faucet washers/cartridge Bad faucet seats

Bad washers or cartridge Bad faucet seats

Partially closed valve Not enough water pressure Blockage in the faucet Partially frozen pipe

Closed valve Broken pipe Frozen pipe

FIGURE 12.24 ■ Troubleshooting showers. (Courtesy of McGraw-Hill)

Symptoms

Faucet drips from spout

Faucet leaks at base of spout Faucet will not shut off

Poor water pressure

No water

Drains slowly

Will not drain Gurgles as it drains Won’t hold water

Probable cause

Bad washers or cartridge Bad faucet seats

Bad О ring

Bad washers or cartridge Bad faucet seats

Partially closed valve Clogged aerator Not enough water pressure Blockage in the faucet Partially frozen pipe

Closed valve Broken pipe Frozen pipe

Hair on pop-up assembly Partial obstruction in drain or trap Pop-up needs to be adjusted

Blocked drain or trap Pop-up is defective

Partial drainage blockage Partial blockage in the vent

Pop-up needs adjusting Bad putty seal on drain

Symptoms Faucet drips from spout

Faucet leaks at base of spout Faucet will not shut off

Poor water pressure

Probable cause

Bad washers or cartridge Bad faucet seats

No water

Drains slowly Will not drain Gurgles as it drains

Won’t hold water

FIGURE 12.26 ■ Troubleshooting laundry tubs. (Courtesy of McGraw-Hill)

Symptoms Faucet drips from spout

Faucet leaks at base of spout Faucet will not shut off

Poor water pressure

No water

Drains slowly Will not drain Gurgles as it drains

Won’t hold water

Spray attachment will not spray

Spray attachment will not cut off

Probable cause

Bad washers or cartridge Bad faucet seats

Bad О ring

Bad washers or cartridge Bad faucet seats

Partially closed valve Clogged aerator Not enough water pressure Blockage in the faucet Partially frozen pipe

Closed valve Broken pipe Frozen pipe

Partial obstruction in drain or trap

Blocked drain or trap

Partial drainage blockage Partial blockage in the vent

Bad basket strainer Bad putty seal on drain

Clogged holes in spray head Kinked spray hose

Bad spray head

Ы

O’*

SIZE AND LENGTH OF SUMP VENTS

For Si: 1 inch = 25,4 mm* 1 fool = 304.8 тіл* 1 gallons per minute = 3 785 L/m.

a. Developed length plus an appropriate allowance forentrance losses and friction due to finings* changes in direction and diameter. Suggested allowances shall be obtained from NBS Monograph 31 or other approved sources. An allowance of 50 percent of the developed length shall be assumed if a more precise value is not available.

b. Actual values greater than 500 feet.

c. Less than 10 feet.

Minimum Required Air Chamber Dimenelone