The WH40 Mechanical Water Heater Time Switch regulates electric water heaters. Utilities in many areas of the country offer two electric rates for residential or commercial customers. One rate has the regular daytime rate, the other is the 'off-peak' rate. This 'off-peak' rate provides customers with lower priced electricity during the nighttime and weekend periods. This time switch allows the customer to shift electricity use into the 'off-peak' time periods in an attempt to save utility costs.
Double pole, single throw
Convenient external override switch
NEMA 1 rated indoor steel enclosure
CSA listed
For use in residential, commercial, industrial, military, and school applications
Additional sets of trippers are available - #156T1978A
Q:can I use this to toggle my water heater from 240v to 120v
by|Jan 25, 2023
1 Answer
Answer This Question
A:Â Hello. This is Bob with Intermatic Technical Support. We appreciate your inquiry. This timer is only designed for 240V. For 120V you can use an EH10. If you have any other questions, you can call us at 815-675-7000 or email us at techsupport@intermatic.com.
by|Feb 16, 2023
Q:The plastic flap inside, that lifts up which hides the voltage cables, has the number 124T1949 on...
by|Aug 20, 2019
1 Answer
Answer This Question
A:Â No. The number on my times is 124T1952-1
by|Aug 21, 2019
1 found this answer helpful
Q:can i use just the 110 volt side? for 110 appliance?
by|Mar 29, 2019
3 Answers
Answer This Question
A:Â Yes, but you can buy a single pole (110 V version) which is less expensive. Be sure the current rating is sufficient for your appliance.
by|Mar 31, 2019
A:Â I doubt it. I have the little gray box it's takes 220 into the box 220 out to the heater. However someone may know better so don't take my word for it.
Richard
by|Apr 1, 2019
A:Â Yes.
by|Apr 1, 2019
Q:Will it work with a neutral wire? I wired it 240V with two hot wires and a ground, but when I tur...
by|Mar 27, 2018
5 Answers
Answer This Question
A:Â Yes. The clock needs a neutral wire for it to work when the power output is turned off.
by|May 5, 2023
A:Â Check with an electrician, also read the instruction in the installation that came with the water heater timer switch.
by|May 5, 2023
A:Â You have two 120 V phases of power in your house. The circuit breakers in a residential panel alternate phases, which are a half cycle out of sync with each other. A 240 V breaker takes up two slots in the panel, taking a hot from each phase. Since the two phases oppose each other the resulting emf [electromotive force] is 240 V. 240 V circuits do not use a neutral wire. They do use a ground wire, to insure that the case of the device is at ground potential, protecting from exposure to high voltage (any voltage over 50 V is considered high voltage). However, the clock motor in this device runs on 120 V, single phase. So, the neutral line is needed for the clock to run. Do not connect the ground wire (usually green, or bare copper) to where the neutral is supposed to go. That would create a ground fault. Follow the wiring diagram in the instructions. If you do not understand this stuff, you would be well served to consult with a licensed electrician.
by|Aug 4, 2022
2 found this answer helpful
A:Â There is no need for a neutral w/ this timer - the motor running the clock is a 240VAC device.
Sounds like you have the source and load connections backwards.
Source (from break panel) is supposed to be connected to screws 1 & 3 - Load is on 2 & 4.
See wiring diagram here:
https://www.intermatic.com/-/media/inriver/7293-8775.ashx/WH40-Specifications-EN
by|Dec 17, 2019
2 found this answer helpful
A:Â Mine is wired for 120 volt, 30 Amp with a hot, neutral and ground wire. The clock works fine
by|May 5, 2023
Showing 1-4 of 23
Customer Reviews
4.3 out of 5
(114)
4.3
out of 114 reviews
85% recommend this product
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Showing 1-10 of 114 reviews
Oct 6, 2019
The Intermatic 40-Amp time is perfect for our water heater...
The Intermatic 40-Amp time is perfect for our water heater and pool chlorinator needs. We used 2 of them. Wiring is straightforward, and available knockouts met our needs for interfacing with conduit.
by
Verified Purchase
Apr 2, 2019
Accidentally ordered different brand - my error. Upon realizing this, ordered the Intermatic to r...
Accidentally ordered different brand - my error. Upon realizing this, ordered the Intermatic to replace an old one. Installation was literally a snap. No rewiring needed, after unhooking the wires, just snapped out the old unit, snapped the new one into the older housing and re-hooked the wires. Thankful that in 30 years, the units were virtually identical because I was not looking forward to having to mount the replacement on a concrete wall and re-run new conduits, etc. Thanks to Home Depot for continuing to stock an old, reliable brand. And further thanks for the ease of ordering via internet, so all I had to do is walk in and put my order number into the locker. No hassle either in returning the other brand that I didn't need. This is especially helpful as I get older and less able to physically walk up and down aisleways.
by
Verified Purchase
Recommended
1 found this review helpful
Jan 1, 2019
Overall I like the timer. Two things though. I have used one at another home for eight years with...
Overall I like the timer. Two things though. I have used one at another home for eight years with no problems. The only criticism I have is the timer is noisy!!! The old one was noisy and the new one I bought last month month is just as noisy. You can hear the timer running. The second thing is the ground wire connection requires the wire to be bent around the screw. On the other terminal connections you don't have to bend the wire. You can leave the wire straight and insert it in the connection and tighten the screw. Thanks
by
DIY
Verified Purchase
Recommended
2 found this review helpful
Oct 20, 2017
Easy to install
Easy to install
by
Verified Purchase
Recommended
Jul 28, 2021
Works great! Keeps excellent time....
Works great! Keeps excellent time.
by
Verified Purchase
Jul 25, 2021
Poor quality and insufficient warranty / support
I replaced the existing Little Grey Box because the trippers stopped working (timer would jam on the tripper). The next one lasted two years before the same thing started again. Support said it was a motor failure. I replaced the motor with a new one from Granger. The new one did not help the issue. I am replacing the box with a digital one. That's three boxes in two years. At minimum, Intermatic should have sent me the replacement motor.
by
2 found this review helpful
Dec 24, 2020
As expected and helps to save on energy bills.....