View Single Post
  #16   Report Post  
Posted to alt.home.repair
albee albee is offline
external usenet poster
 
Posts: 83
Default electric water heater question

On Fri, 14 Aug 2009 20:19:55 -0500, "Ralph Mowery"
wrote:


"albee" wrote in message
.. .
Thanks. I just re-checked just to make sure, and still the same,

although I did confirm that it's 240 between both poles. Actually,
fwiw, it's 237, and going from each to the neutral is 118 and 117 (I
think; could've been 118 and 119). But, clearly not zero.

I was measuring at the breaker by touching the screws, but thought it
possible that the wires weren't screwed in tightly. I tried testing
behind the screws, but couldn't get a reading. Am I right that
touching the screws won't necessarily give me what's coming OUT of the
breaker? I wiggled, or tried to, the wires, but didn't note any
looseness, and re-checked at the heater, still with no voltage.

I guess next step is to undo and re-attach the wires at the breaker?
Haven't done that yet, and hesitate to if not needed.


There is no use to worry about a couple fo volts differance.

Cut off the breaker and test to make sure the voltage is really off.
Switch the meter to ohms and see what the resistance is to the heater. It
should be very low on the two wires and almost an open circuit to the ground
wire. If the resistance is low on the two wires in the breaker box comming
from the heater, the breaker must be bad. If it is almost an open circuit,
go to the heater and measuer the resistance of the wires going to the
breaker. If low, you have a bad wire. If high, the element is probably
open, you can measuer that.

You may also want to make sure the power is off, then hook both hot wires to
the ground at the water heater. Then go to the breaker box and check each
wire to ground. If one is low and one is ooen, you have just found your
open wire and will have to trace the wiring and maybe replace or splice it.

Thanks for the great, specific advice! In exchange, I have a feeling
I'm going to be asking a stupid question.
So, I turned the breakers off (two 30 amp ones), and pulled the wires
out of the breakers to measure the resistance between them. Right? I
get 1. Likewise, when testing from each wire to the neutral bar
holding all the white wires, that earlier I used to measure the 120 v
coming into each main wire to the box.
I went to the heater, and also measured the resistance between the
same wires coming out of the wall, and also got 1. likewise when I
went from one of the wires to a ground (metal part of the heater).

Did I do this right? what does this tell us? Sorry for my ignorance,
and thanks so much for the help.