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How to install water heater timer

 Page 1 of 3: Overview /and Gather materials
Skip to Page 2: Connect the wires
Skip to Page 3: Wiring details
2023
install water heater timer Project overview: NO Neutral
Use for timers and switches that do not require Neutral
Ordinary switches and some timers do not require Neutral, just a Hot wire, listed below.
Attic installation shown in illustration, wiring applies to any location, and any electric water heater, or other 30 amp load.

Buy:
Intermatic ST01c timer/ 1 year warranty
ST01a almond
Intermatic ST01K combination timer

Spring wound timers
Leviton LTT countdown

Resources for switches:
Wiring for all switches and timers
Control 2 water heaters with 1 switch
Control water heater with 2 switches
Control 1 water heater with 30Amp switch
install water heater timer Project overview: Requires Neutral
Use any programmable timer, zwave or wifi device that is rated for resistive load.
Use Hot and Neutral from nearby 120 volt outlet to power device.
Rule of thumb: Outlet box will always have Hot and Neutral, Switch box will always have Hot but not always Neutral, Ceiling box with light will always have Neutral but only has Hot when light is on.

Buy:
Programmable timer
Countdown timer
Zwave switch
Wifi switch

Resource:
Compare programmable timers
Compare countdown timers
Alternative using box timer

Buy 240 volt/ 7-day:
Intermatic EH40 timer at Amazon
30 amp timers

Resource:
Compare box timers
How to wire EH40 timer
                    Project materials
Intermatic EI500  Grasslin ET616    Choose timer or switch
Buy:
Intermatic ST01 timer
Spring wound timers

Buy: requires neutral
Programmable timer
Countdown timer
Zwave switch
Wifi switch

Resources:
Compare programmable timers
Compare countdown timers
Old work boxe Old work box
Use for new switch, timer etc.
Drop wire into wall, Cut hole to fit box, reach in and pull wire through hole, put wire inside box, push wire back into hole as you insert box into hole
Buy:
Thomas and Betts old work box at Amazon
Old work boxes at Amazon

Resources:
See How to install old-work box
Contactor Contactor with 240V coil for no Neutral
Contactor with 120V coil for requires Neutral
Contactor controls 30 amp water heater load, rated 1 million operations
Buy:
240Volt coil 2-pole contactor
120Volt coil 2-pole contactor

Resources:
Read more about contactors and relays
carlton 6x6x4 junction box
Plastic 6x6x4


6X6X4 Metal box w/ Contactor


Choose metal or plastic 6x6x4 junction box

Plastic box: no pre-drilled holes, but easy to drill... must drill size 3/4" holes for Wire connections, size 1/2" hole for fuseholder, and 3/16" holes for bolts. Plastic box does not need ground screw connected to box.
Buy Plastic
Cantex 6x6x4 PVC plastic enclosure with cover at Amazon
Bud industries 11x7x5 box without knockouts
Metal box has knock-outs for 1/2" and 3/4" connector ... must drill 1/2" hole for fuseholder, drill 3/16"  holes for bolts, and drill and thread hole for 10-32 ground screw. Metal box must be grounded.
Suggest pre-painted steel box for appearance.

Buy Metal
Bud industries 6x6x4
Nema 3R Outdoor box
Hinged door/ 6x8x4

Polycarbonite enclosure
Bud industries boxes at Amazon
Arlington boxes at Amazon

Resources:
See more about boxes
2T511GA enclosure Choose metal junction box
Fits multiple contactors and relays
see image
Outside dimensions: 9-3/8x 5-1/2 x 3-5/8

Nema 3R indoor/outdoor enclosure with pre-installed ground screw
1/2 and 3/4 knockouts located sides and bottom
Painted metal, weathertight hinged door, locking hasp

Buy:
2T511GA gray painted
2T2485GA beige painted
tapered drill bit Tapered drill bit for plastic or metal box
Step drill bit for any size hole
Buy
Step drill bits at Amazon
Neiko tapered drill bit 1/4"-1-3/8 holes
Black and Decker Complete guide to wiring

Resources;
See inside main breaker box
household wire
120Volt 14-2 wire will have Black-white wires
240Volt, 10-2 wire can have red-black or white-black wires... always add piece of black tape to white wire when used for 240Volt power. Adding black tape will signal that wire carries power

Resource:
See wire color code and amp ratings
Lengths of wire

Buy:
White/ #14 gauge wire for 15 amp
25 foot 14-2 NMB indoor wire with ground
50 foot 14-2 indoor wire with ground
100 foot 14-2 indoor wire with ground
100 foot 14-2 UF outdoor burial with ground
Yellow/ #12 gauge wire for 20 amp
25 foot 12-2 NMB indoor with ground
50 foot 12-2 indoor with ground
100 foot 12-2 UF outdoor burial with ground
#10 wire required for water heater
Orange/ #10 gauge for for 30 amp circuits including water heater
25 foot 10-2 NMB indoor with ground
100 foot 10-2 NMB indoor with ground
50 foot 10-3 indoor with ground
Resources:
See wire color code and amp ratings
fuseholderBusman fuse holder Buy fuseholder and 15 amp fuse
Used for No Neutral installation
Or when nearby hot wire is not available

Buy:
Panel mount fuse holders at Amazon
ANL fuseholder
Buy fuseholders at Amazon
Ceramic fuses at Amazon
Din rail fuseholder
10 x 38 mm fuse

Resources:
Read about fuseholders

Blue 14-16 gauge wire
Yellow 12-10
Terminals
Use to connect 120 volt wires to contactor see image
Add solder when crimping to solid wire
Buy:
Terminal kit with crimp tool
Blue 14-16 gauge
Yellow 12-10 gauge
Assortment
Resources:
More about terminals
wire nuts      Wire connectors

Buy:
Wire connectors at Amazon
Push-in wire connector up to 14-12 gauge

Resources:
How to install wire connector
Optional Indicator light
Buy:
240Volt Pilot light at Amazon
Best 240 volt
120Volt pilot light at Amazon
Indicator lights at Amazon
NSI indicator lights
Resources:
See illustration of 120Volt & 240v pilot light
cable staples Staples and clamps
All wires, conduit and boxes must be firmly attached to structure (2x4, siding etc)

Buy
Cable staples plastic
Cable staples metal
1/2" conduit clamp
romex connector Wire connectors
All wires and conduit going into metal or plastic box must be firmly attached to the box

Buy
Metal 1/2" squeeze connector
Flexible conduit connector
PVC terminal adapter
Raco locknut
8-32 bolts 8-32 x 3/4" bolt w lock nut

Buy:
8-32 tap
Tap handle
ground screws Ground screws
Needed to connect ground wire to metal box
Not needed with plastic box
Use 10-32 tap to thread hole

Buy:
100 pack ground screws
8-32 tap
Tap handle
You have the materials.
hand Go to Page 2: connect the wires.
Insteon 30 amp z-wave load controller
Insteon load controller manual




Buy
Tools
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DEWALT
Black and Decker
Stanley
SKIL
Makita
Porter-Cable
Bosch

Irwin Hand tools
Klein hand tools
Fluke electrical testing
Dremel hobby tools

Campbell Hausfeld air powered
Tekton automotive

Powerbuilt automotive
Saws and saw blades

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