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Flashcards in Pump Selection Deck (27)
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1

What is Head Loss?

Resistance to flow measured in feet of head or sometimes PSI

2

How is a pump selected?

GPM and Head Loss of the system

3

What is BHP?

Brake Horse Power is a measurement of power consumption

4

What is a HP?

Horse Power is used to indicate a pump's motor size.

5

RPM

Rotations per minute is the measure of motor speed

6

How does a pump work?

Pumps use suction or pressure to raise or move liquids

7

What are the two basic pump types?

Inline and End Suction

8

What is the rule of thumb for inline applications?

Lower flow applications (below 100 GPM) and 7.5 HP for the motor

9

When is an inline multistage pump used?

High head / low flow applications (e.g. a high-rise bldg. when you're on a lower floor and need extra pressure)

10

What is the rule of thumb for end suction applications?

Normally flows between 100-2500 GPM

11

What is the difference between base mounted and closed coupled?

The impeller is mounted directly to the motor. Base-mounted pumps share a baseplate. Base mounted is preferred.

12

How many ways are there to configure your pumps in a hydronic application?

Single, parallel and series pumping

13

Explain single pump configuration

Used when there is no redundancy requirement

14

Explain parallel pumping configuration.

Used when one pump cannot handle flow requirement or pump redundancy is required

15

Explain series pumping

Used when one pump cannot handle head pressure requirement or pump redundancy is required

16

What is NPSH stand for?

Net Positive Suction Head

17

What is cavitation?

The liquid in the pump turns to vapor because there isn't sufficient NPSH at the suction end of the pump. Can't meet system curve

18

How can you make sure you have enough NPSH?

By making sure that each pump is capable of crossing the system curve and selecting non-overloading motors that won't be overloaded at any point on the pump curve.

19

What RPM should you select for your motor to limit noise issues?

1750 RPM

20

Common application for inline pumps

Recirculation applications (low flow applications)

21

Common application for multi-stage vertical pumps?

Booster pump applications (high head, low flow)

22

Common application for vertical centrifugal pumps?

Booster pump applications (limited space)

23

Common application for Diaphragm pumps?

Process applications (pumping slurries, solvents, and high-viscosity fluids)

24

What is a sump pump?

A pump used to remove water from a water-collecting sump basin

25

What is a sewage ejector pump?

A pump is designed to pump sewage uphill in order to reach the sewer main, is necessary when a plumbing fixture is installed below the main sewer or septic line.

26

Why would you need to use a recirculating pump?

for maintaining temperature in DHW systems.

27

How does a VFD work?

A variable frequency drive controls the speed of an AC motor by varying the frequency supplied to the motor