household water system

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Household Water Systems
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Household Water System Components

• Water Source (well, spring, pond, or cistern)
• Pump
• Pressure Tank
• Pressure Switch
• Check Valve
• Piping
• Optional Treatment Equipment
• (Softener, Filter, Disinfection Unit, etc)

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Typical Shallow-Well Water System


SUPPLY PIPE TO HOUSE
PUMP POWER CONTROL BOX



SUCTION PIPE

PRESSURE TANK PRESSURE SWITCH
CHECK VALVE
SHALLOW-WELL JET PUMP
WELL CASING
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Water Pump Options
Suction Lift (feet) Pump Type
0 18 Horizontal Centrifugal
0 28 Shallow-Well Centrifugal Jet
0 200 Deep-Well Centrifugal Jet
0 500 Multi-stage Submersible
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PRESSURE SWITCH
Pump House with Shallow Well Pump
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Jet Pump Installations
Deep-Well Jet Pump (Two-Pipe System)
Shallow-Well Jet Pump
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To Pressure Tank

• Jet Pump Schematic Diagram
• Increases practical suction lift by diverting
  part of the pump discharge to the ejector on the
  lift pipe
• The greater the suction lift, the greater the
  percentage of discharge water must be diverted
• Maximum practical lift is limited to
  approximately 200 feet by economics

Pressure Pipe (Return Flow)
Lift Pipe (Upward Flow)
Jet Ejector (Venturi)
Nozzle
Intake Pipe
Water
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Deep-Well Jet Pump Ejector Units
Packer System Return Flow Lift Pipe (w/
Venturi) Nozzle Foot Valve Packer Suction Pipe
Two-Pipe System Well Cap Return Pipe Lift
Pipe (w/ Venturi) Nozzle Foot Valve Intake
Strainer
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• Submersible Water Pumps
• - Good for deep wells
• High efficiency
• Wells as small as 4 diameter

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FROST LINE
Submersible Pump with Pitless Adapter

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Pressure Switch

• Controls water pump
• Turns on when system pressure drops to 20 (30)
  psi
• Turns off when system pressure rises to 40 (50)
  psi
• Low pressure shut-down in case well water level
  drops

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Pressure Tank

• Is not meant to provide household water storage
• Delays pump turn-on and extends pump run time
• Eliminates frequent, short On/Off cycles which
  can burn up the pump motor
• Volume of pre-charged tank should be at least
  6 times the delivery of the pump in 1 minute
• Volume of uncharged tank should be at least
  10 times the delivery of the pump in 1 minute

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Pressure Tank
Pipe Plug (to be removed when system is drained
to correct waterlogging)
Typical uncharged pressure tank (no air
bladder/diaphragm) installation
Pressure Switch
Main Power Cutoff Switch
Delivery Pipe from Pump
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Useable Storage Capacity of Pressure Tanks Over
Normal Operating Range (Not Pre-charged)
82 gallons
Water Level at
12 gallons
42 gallons

40 lbs 20 lbs
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Examples of Pre-charged Pressure Tanks
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Effect of Waterlogging on Useable Pressure Tank
Capacity
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Waterlogging
Pipe Plug (to be removed when system is drained
to correct waterlogging)

• To correct waterlogged pressure tanks
• -Turn off power to pump
• Open a faucet to drain system
• Remove pipe plug at top of tank to let air into
  tank and finish draining system
• Replace pipe plug (use teflon tape or pipe
  compound to seal properly)
• Close faucet
• Turn on power
• Repeat this process whenever the pump begins
  starting immediately every time a faucet is opened

Power Switch
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Controlling Waterlogging in Pressure Tanks
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Submersible Pump Check Valve Cutaway
Water Flow
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Household Water Requirement

• Typical Usage 50-100 gallons/person-day
  (drinking, bathing, laundry, toilet flushing,
  dishwashing, cooking, etc.)
• Well Flow Rate Requirement
• Minimum Acceptable Rate 5 gpm
• Preferred Rate 10 gpm
• Minimum Fire Protection Rate 20 gpm

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Household Water Requirements
Use Flow Rate (gpm) Volume per Use (gal.)
Washing Machine 5 20-35
Dishwasher 2 6-20
Shower/Bathtub 5 20-60
Toilet 3 1.6-5.0
Kitchen Sink 3 2-4
Water Softener Recharge 8 50-150
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Farmstead Water Requirement(Flow Rate)
Use Minimum Preferred
Stock Auto. Waterers 0.5 gpm 2 gpm
Poultry Auto. Waterers 0.25 gpm 1 gpm
Milkhouse Cleaning 3 gpm 5 gpm
Manure Washdown 5 gpm 10 gpm
Outdoor Hydrant 5 gpm 10 gpm
Outdoor Hydrant (Fire) 10 gpm 20 gpm
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Intermediate Water Storage

• Improves usability of low-yield wells
• Well pump operates at low flow for extended
  periods (overnight) to fill storage tank
• Pressure pump uses water from storage to supply
  immediate household demand
• Minimum intermediate storage capacity should be
  at least equal to daily household water use (2-3
  days storage capacity preferred)

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Intermediate Storage for Low-Yield Wells
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Low Yield Well Water System
Inlet from Well Pump
Intermediate Storage Tank (filled by submersible
well pump)
Pressure Pump
Check Valve
Pressure Tank
Pressure Pump Suction Line
Supply Line to House
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Water Treatment Equipment

• Disinfection Equipment
• Filters
• Water Softeners

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Water Disinfection Options-Bacteria Viruses-

• Chlorination
• Shock chlorination
• Continuous chlorination
• Dry pellet chlorinator
• Chlorine solution feed pump
• Chlorine solution venturi injector
• Ozonation
• Ultraviolet Irradiation

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Shock Chlorination

• Use laundry bleach (5.25) w/ no additives
• Pour 4 pints of bleach into well vent for each
  100 gallons of water in system
• Recirculate water into well for 20 minutes
• Open all outlets until bleach is smelled
• Let system stand idle overnight (4 hrs minimum)
• Flush system
• Re-test for bacteria after 10-14 days of use

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Dry Pellet Chlorinators

• -Electric powered (110 or 220 volt)
• -Controlled by pump controller
• Few moving parts
• Uses calcium hypochlorite tablets
• Treats water in the well
• Longer Cl contact time
• No solutions to mix
• Treats up to 20 gpm

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Venturi Solution Injector

• Injects any liquid solution
• Injection rate proportional to water flow rate
• Adjustable over wide range of flow and injection
  rates

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Metering Pump

• Injects any type of solution
• Controlled by water pump controller
• Constant injection rate
• Adjusts to wide range of flow and injection rates

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Ultraviolet Disinfection Unit
SIGHT PORT
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Water Treatment Options- Iron or Manganese -

• Shock Chlorination
• Continuous Chlorination
• Dry pellet chlorinator
• Chlorine solution feed pump
• Chlorine solution venturi injector
• Ozonation
• Oxidizing (Greensand) Filter
• Ion Exchange Water Softener

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Iron Treatment Options
Iron Level (mg/l) Iron Bacteria Clear or Red When Drawn pH Treatment Method
0-5 No Clear 7 Softening
0-5 Yes Clear 7 Shock Chlorination or Oxidizing Filter
5-20 No Clear 7 Shock Chlorination or Oxidizing Filter
5-20 Yes Clear or Red 7 Oxidizing Filter, Shock or Continuous Chlorination
0-20 No Red 7 Oxidizing Filter
20-30 No Clear or Red 7 Continuous Chlorination or Oxidizing Filter
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Water Treatment Options-Corrosion-

• Neutralizing Filter
• Limestone chips
• Marble chips
• Caustic Soda (NaOH) Feeder
• metering pump or venturi injector
• Soda Ash (Na2CO3) Feeder
• Metering pump or venturi injector

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Water Treatment Options-Hydrogen Sulfide (H2S)
Rotten Egg Odor-

• Activated Carbon Filter
• Oxidizing Filter
• Shock Chlorination
• Continuous Chlorination
• Dry pellet chlorinator
• Chlorine solution metering pump
• Chlorine solution venturi injector
• Ozonation

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TDS/Mineral Treatment

• Reverse Osmosis
• Distillation

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(No Transcript)
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4-stage Reverse Osmosis Unit with Tank and Faucet
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Reverse Osmosis Systems

• Reduce mineral concentrations by ? 90
• 15 gallon/day under-sink units ? 150-300
• Require pre-softening with hard water
• Operate on water system pressure (40 psi)
• WastewaterTreated water ratio ? 4 or 51
• Membranes ?70-100 each ? 5 year life

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Distillation Unit
Vaporization Chamber
Gas Vent
Condensing Coil
Raw Water Inlet
Rising Steam
Distilled Water
Drain
Heating Element
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Countertop Distillers

• initial cost 150-1000
• 4-8 hours/gallon treatment rate
• 2.75-3.0 kWh/gallon energy consumption
• removes 99.9 of all contaminants
• electric co-ops often subsidize purchase

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Carbon Filters

• Remove contaminants by adsorption on carbon
  particle surface
• Hierarchy of contaminant adsorption
• Saturated filters can actually increase
  concentration of some contaminants
• Not effective on nitrate, hardness or bacteria
• Filter cold water only
• Bigger is better - more surface area

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Cartridge Filters
Carbon Cartridge (taste, odor, chlorine,
organics) Particle Cartridge (sand, sediment)
Filter Wrench Filter Housing
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Ion Exchange Water Softeners

• Exchange sodium ions for calcium and magnesium
  ions in water
• Increase EC somewhat
• May be dietary hazard - hypertension (adds ?140
  mg/l of sodium in Hard water)
• Use potassium salt (KCl) for health reasons

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Ion exchange softeners replace Ca and Mg with
Na ions. Zeolite medium is recharged with Na by
NaCl brine when depleted.
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Ion Exchange Water Softener with Sensor-
Controlled Recharge
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Softener Selection Considerations

• Required grain capacity
• Daily water use (household population)
• Water hardness
• Desired regeneration schedule
• Initial cost
• Water conservation
• Other (Iron removal, etc.)

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Ion Exchange Water Softener Capacity

• Rated by grains of hardness treated between
  regenerations
• 1 grain/gallon (gpg) 17.1 mg/l
• Example
• Water hardness 200 mg/l 200/17.1 11.7 gpg
• Softener Capacity 30,000 grains
• Household Population 4 persons
• Calculate
• Water Use 4 persons x 50gal./person-day 200
  gal./day
• Daily Hardness Treated 200 gpd x 11.7 gpg
  2339 grains/day
• Regeneration Interval 30,000 grains/ 2339
  grains/day 12.8 days

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Recommended Softener Sizes
Pump Capacity (gpm) Softener Capacity (grains) Water Hardness (mg/l)
3 4 10,000 350
5 6 15,000 500
7 8 20,000 850
9 12 30,000 1200
12 20 40,000 1500
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Ion Exchange Water Softener Recharge Control
Method
Water Use
Initial Cost -

• -Time Clock
• -Flow Meter
• -Hardness Sensor

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Typical Programmable Water Softener Controller
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Water Softening

• Permanent magnet water softeners dont work
• Electrostatic and catalytic descalers may
  descale water, but dont soften it
• Scale will not buildup on pipes, water heater
  elements, bathtubs etc.
• Sudsing action of soaps is not improved

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Private Water System Resources