40-Amp 240-Volt Electric Water Heater Time Switch

A:  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.

A:  No. The number on my times is 124T1952-1

A:  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.

A:  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

A:  Yes.

A:  Yes. The clock needs a neutral wire for it to work when the power output is turned off.

A:  Check with an electrician, also read the instruction in the installation that came with the water heater timer switch.

A:  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.

A:  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

A:  Mine is wired for 120 volt, 30 Amp with a hot, neutral and ground wire. The clock works fine