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Troubleshooting

Pumping system troubleshooting

Symptom

Cause

Remedy

There is no circulation

Air-bound system

Vent the system

The impeller or piping is clogged.

Locate and remove the obstruction.

The system valve is closed.

Open

The electrical circuit for the pump is

broken.

Check all related low and line voltage

circuits.

There is inadequate circulation.

Air-bound system

Vent the system.

The impeller or piping is clogged.

Locate and remove the obstruction.

The impeller is damaged.

Replace pump.

The pump is too small.

Replace the pump if single speed. If

three speed switch to higher setting.

Partially air-bound pump

Vent the pump casing.

Improper motor speed

Check the wiring and the voltage.

There is pump or system noise.

Entrained air

Vent the system.

Pump cavitation

Lower the pump or raise pressure or

relocate (see note below).

Excessive water velocity

Install balancing cocks or parallel

piping.

Pipe vibration

Provide adequate pipe support.

There is premature failure of pump

components.

Improper pump (size/type)

Replace

Improper pump location

Relocate

Excessive water treatment

Check the manufacturer’s

instructions.

Pump operating close to or beyond

the end point of curve.

Balance the system.

Excessive piping load

Provide proper pipe support

There are seal failures within a 1–year

period or less in a closed system.

Excessive dirt, sand and oxides

Clean the system.

Excessive or improper water

treatment

Check for proper water treatment

recommendations from pump

manufacturer.

Pump Cavitation:
1. Improper selection
2. Compression tank location

1. Check pump operation on its

curve — overloading

2. High head pump must have

compression tank on suction

side of pump.

Excessive temperatures

Check the type of seal and maximum

operating temperature from the

manufacturer.

Pumps run without fluid

Pumps must be primed before

operation.

There is seal pitting, oxygen

corrosion, magnetic iron oxide.

Caused by wear and excessive

amounts of free oxygen.

Check if system has a constant leak.

Fresh water feeding carries oxygen

into the system.

Troubleshooting

16

NRF

-25,36,45/NBF

-25,36, and 45 Circulator Installation, Operation, and Maintenance Manual

Содержание Bell & Gossett NRF-25

Страница 1: ...Installation Operation and Maintenance Manual NRF 25 36 45 NBF 25 36 and 45 Circulator...

Страница 2: ......

Страница 3: ...ump orientation 8 Change the conduit position 8 Install suction and discharge flange connectors on the pipe ends 9 Connect the wiring 9 Wiring diagram 10 Install a check valve 10 Commissioning Startup...

Страница 4: ...cautions to prevent physical injury Any pressure containing device can explode rupture or discharge its contents if it is over pressurized Take all necessary measures to avoid over pressurization Oper...

Страница 5: ...re indicated by the following specific symbol Electrical Hazard These are examples of other categories that can occur They fall under the ordinary hazard levels and may use complementing symbols Crush...

Страница 6: ...fore you handle them Make sure that the product has been thoroughly cleaned Disconnect and lock out power before you service the pump Check the explosion risk before you weld or use electric hand tool...

Страница 7: ...service and repair work is done by Xylem authorized personnel Genuine Xylem parts are used Only Ex approved spare parts and accessories authorized by an EX approved Xylem representative are used in Ex...

Страница 8: ...or are missing 3 If applicable unfasten the product by removing any screws bolts or straps For your personal safety be careful when you handle nails and straps 4 Contact the local sales representativ...

Страница 9: ...g applications in hydronic and solar systems Indoor use only Do not use in swimming pools and marine areas Xylem recommends that you use bronze or stainless steel booster pumps for pumping potable wat...

Страница 10: ...installation If the pump is already installed see Remove the pump from an existing system page 15 before proceeding Change the conduit position CAUTION Burn or projectile hazard Make sure the power i...

Страница 11: ...Do not overtighten 3 Line up the vertical and horizontal piping so that the bolt holes in the pump flanges match the bolt holes in the pipe flanges NOTICE Do not attempt to spring the suction or disc...

Страница 12: ...ounded Use a grounded metal conduit or ground the pump back to the service using a correctly sized copper conductor Connect the ground wire to the green grounding screw in the wiring compartment The c...

Страница 13: ...D It is not advisable to install circulators in an attic or upper floor over finished living space If the circulator must be installed over head or over expensive equipment provide adequate drainage i...

Страница 14: ...marine areas Failure to follow these instructions could result in serious personal injury death and or property damage Prepare the system 1 Clean and drain closed heating and cooling systems 2 Refill...

Страница 15: ...5 0 0 0 10 20 30 40 50 60 0 1 5 3 2 1 0 40 30 20 10 0 gpm m3 hr l s CENTRIFUGAL PUMP SERIES NRF 36 SPEED 1 Figure 4 Centrifugal pump series NRF 36 SPEED 3 SPEED 2 SPEED 1 100 kPa M FT 50 0 10 5 0 0 0...

Страница 16: ...series NRF 25 with check valve 100 kPa M FT 50 0 10 5 0 0 0 10 20 30 40 50 60 0 1 5 3 2 1 0 40 30 20 10 0 gpm m3 hr l s CENTRIFUGAL PUMP SERIES NRF 36 SPEED 1 SPEED 3 SPEED 2 Figure 7 Centrifugal pump...

Страница 17: ...mp If no valves are installed you might need to drain the system 2 Drain the system WARNING Allow all system and pump components to cool before you handle them to prevent physical injury a Allow the w...

Страница 18: ...re of pump components Improper pump size type Replace Improper pump location Relocate Excessive water treatment Check the manufacturer s instructions Pump operating close to or beyond the end point of...

Страница 19: ...The pressure at some point in the pump falls below the vapor pressure of the water causing flashing and the formation of bubbles which are carried into the volute where the higher pressure causes them...

Страница 20: ...s In more than 150 countries we have strong long standing relationships with customers who know us for our powerful combination of leading product brands and applications expertise backed by a legacy...

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