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2012

How to wire EH40 water heater timer/ EH10/ WH40/ WH21

Timers shown are safe for 1 residential water heater.
EH40
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Terminals 1 and 2 power 240V electronic clock
EH40 water heater timer

Programming for timer is on label located on inside of timer door.
7-day 7-programs
10 gauge wire, 30 amp breaker rated for 4500+ watt element
Timer rated 30 amp
EH40 water heater timer
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240V EH40 manual

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Basic water heater circuit

How to wire off-peak water heater

How to wire water heater thermostats

Romex connectors
How to twist wire
Wire nuts
Color code wire
EH10 & EH40 are battery operated timers/

Battery compartment located beneath buttons
Size A battery lasts 2-3 years

EH10 water heater timer

  
Terminals 1 and 2 send power to 120V clock.
Jumper hot wire from terminal 2 to terminal 3.
Neutral wires connect to terminal 1
How to wire Intermatic EH 10 timer for 120Volt water heater

Programming for timer is on label located on inside of timer door.
7-day 7-programs
Ground wires are kept away from other wiring.
Romex connectors used where wire enters metal box.
Tighten screws very tight against copper wire.

12 gauge wire, 20 amp breaker rated for 3500 watt element
Timer rated 30 amp
EH10 timer controls 240Volts
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EH10 timer controls 240Volt water heater

10 gauge wire, 30 amp breaker rated for 4500+ watt element
Timer rated 30 amp
romex connector

WH40 hot water heater timer

WH40
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240V clock wires from back of timer connect to terminals 1&3
WH40 water heater timer
WH40 water heater timer
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240V WH40 manual
120V WH21 manual
Timer rated 40 amp

How to set WH 40 timer
WH40 timer
How to set WH40

Video
Manual override reverses current program until next tripper returns timer to regular schedule
Intermatic trippers Replacement tripper Pins and clock motors for WH40 and Intermatic
WH40 uses WG1573 clock motor
WH40 uses 156T1978A tripper
Clocks and trippers at Grainger

Troubleshoot Intermatic timer
40 amp water heater timers
Water heater timer for 2 water heaters
Two water heaters
WH21 timer
WH21- larger image
WH21 / 23 amp water heater timer
WH21 manual
Troubleshoot WH21 timer
Figure volts amps watts for water heater
color-code household wire Color code wire

Romex connectors
How to twist wire
Wire nuts
 

What is difference between 120Volt and 240Volt
?
Inside Main Breaker Box
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Inside main breaker box are Three busbars.
One busbar is Neutral busbar.
Two busbars are Hot busbars.
Each Hot busbar is 'out of phase' with the other.

All residential circuits require Two wires to complete circuit.
120Volt circuit requires 1 Neutral wire and 1 Hot wire.
Hot wire can come from either Hot busbar.
By Code, these wires are Black-Hot and White-Neutral.
If either wire is interrupted, the circuit turns OFF.
By code the Black Hot wire is switched ON-and-OFF.

240Volt circuit also requires 2 wires to complete circuit.
In the case of 240V, the circuit requires 2 Hot wires.
One Hot wire from each 'out of phase' busbar is required to complete 240Volt circuit.
These wires can be Black and White or Black and Red, and with heavier gauge wires, like 6 gauge and 4 gauge, the wires are Black and Black.
If either wire in 240V circuit is interrupted, the circuit turns OFF.
See 30 amp switch turning off water heater
Bare ground wire connects to Neutral busbar as redundant safety.

Electricity is a wave that oscillates at 60 cycles per second. This is called 60 Hz.which appears on electric device labels.

Both Hot busbars are identical except out of phase with each other. 240Volt is like adding an extra cylinder to the engine, and gives added power.

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 EJ500 Utilitec Woods Woods ST01C  ST01C ETW350 Aube T1032Aube Intermatic EI500Intermatic
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Timex
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