In alt.home.repair, on Sun, 02 Jul 2017 20:44:02 GMT, Dino
m wrote:

replying to Fred, Dino wrote:
I manage a building with a 8 apartment units. The single transformer operates
all eight doorbells. After two or three iterations, the 16 volt just kept
burning out within one or two days, or one or two weeks.

Before it burns out, does it work fine?

If so, it seems very unlikey to me that more than one doorbell button is
pressed at one time, so I don't see why the size you've been buying is
not adequate, just as it would be for a single family. Unless there is
a short in a button or somewhere else and the transformer is outputting
all the time. I'd disconnect the wires to it and measure the ohms
between the two wires when NO one is pushing any buttons. I think it
should be close to infinite. Then for kicks, I'd have someone else push
each button in turn and check the ohms for each of them. Should be
about the same if all the bells are the same and if the extra distance
for some has little effect.

I'd take the lowest ohm reading, divide it into the volts (16 or so) to
get the amperage and I'd compare that to the rate amperage of the
transformer. I'd expect the transformer to be a lot higher.

. I just installed a
24-volt for sugar and grins, and it seems to be working okay with the
exception that one of the illuminated buttons the the light has burned out.
The lights on the other doorbell buttons are much brighter and much warmer so
it is a bit of a concern.

What they said. I'd disconnect the 24v. transformer right now and let
people yell up to the window, like normal people do. Or throw pebbles
or cellphones against the window. Or call up with their cell phoen.