I needed to replace my old doorbell chime. I purchased a new, simple
chime, that merely said "low voltage" (e.g. wired, not wireless) on the
outside of the box. My door bell transformer puts out about 22 volts.
(It's probably supposed to be 24). The instructions to the new unit,
which has the name "Zenith" (probably under license by the Zenith
company to Home Depot) says that it runs on just 16 volts.
The unit has two solenoids, one for the front door, and another that has
the second tone blocked for the back door. Would 22 volts be too much
for the unit? I'm not going to be replacing the transformer on the
breaker box, so my options are to use the unit as is, return the unit
for something else or calculate what size resistor to put in series so
that the voltage received by the chime is 16 volts.
Does anybody have any experience with door bell voltage? Is it
important to have the exact voltage?
No, don't sweat it. The transformers are never exactly 24 volts, even if
that's what's stamped on them. Close enough is close enough. As they
say, it ain't rocket science.
Think about it: the doorbell solenoids are only energized for moments at
a time (unless some kid leans on your doorbell or something), so they'll
handle it just fine.
Napoleon won the battle of Waterloo. The German Wehrmacht won World War
II. The United States won in Vietnam, and the Soviets in Afghanistan.
You know that e.g. means "for example", right? If so, I don't
understand your sentence. ("i.e. means "that is". For some reason,
more than half the population seems to have this backwards. :) )
No. Especially in the case of a doorbell, where people only press the
button for a couple seconds.
I wish though that I could remember what the voltages normally are.
Everything was fine for me when I had a doorbell like your new one in
the front hall, and bell with a clapper in the basement, so I could
hear the doorbell when I was in the basement.
Then I saw a really nice doorbell at a very big discount, pretty much
like the one in the hall but much nicer. So I put the new one in the
hall and the one from the hall in the basement. Great, but now the
transformer wasn't big enough to power the two. It was either 12, 14,
or 18 volts. I think it was less than 18. I went to the store and
bought the only other size they had, which was more than 14, either 18
or 24. Then the first floor hall doorbell was too loud, and every
time the mailman rang the bell, the glass and wood breakage detector
set off my home burglar alarm! Fortunately I didn't have monitoring,
but otoh, it might have taken less than a year to find out about this
if I did. It was a year before someone told me about the false
There is nothing very fragile in your new doorbell and 24 volts isn't
enough to melt or overheat the wires, probably even if they leaned on
the doorbell for hours, but certainly not in 15 seconds.
I didn't see one, but I did see a higher voltage xformer, so that's
what I got. It's been ten years since I did this and everything has
I forgot to say before that in order to stop the false alarms, I put a
resistor in series with the first floor doorbell. I started with a
potentiometer to find the minimum resistance that would keep the glass
breakage detector from setting off the burglar alarm. When I found
the value I replaced the pot with a cheap fixed resistor.
Heh. Having spent many years of declining and conjugating and Latin nouns
and verbs, how could I forget? Actually e.g. stands for "exempli gratia"
which pretty much means something like "for the sake of example." I.e.
stands for "id est," which could mean this is or that is. So writing a e.g.
was a brain dump on my part. (It happens sometimes, like when I type the
wrong homonym and then wonder how I wrote that!) I hope this helps clear up
Thanks. I wasn't worried about a few seconds, but I may be worried if the
button sticks and the coil is energized for days while we're away. Anyway I
wired it up, and the solenoid doesn't seem to work too well. If I press and
release the button very quickly it sounds ok, but otherwise it the striker
seems to get stuck or not hit the chime very hard.
Never seen a doorbell with the secondary fused.. Shorting the
secondary won't blow the 15 amp fuse or breaker on the primary.
I'm sure it was not a p-p reading - it was just an open circuit
voltage on an impedence protected transformer. The resistance is high
enough to limit the maximum current, and to more or less regulate the
voltage to 24 with the design load applied.
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.. 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
The problem is NOT the 16 volts being to low, it is the VA rating of
the transformer (which REALLY only comes into play if more than one
bell is rung at once) What you need is a 16 volt transformer rated
30va or more.. Many are only 10 va - get the highest rated one you can
buy - Try an edward 88-250 - good for 160va at 16 volts. Won't burn
out the button bulbs, the bells, OR the transformer.
Sun, 02 Jul 2017 20:44:02 GMT
in alt.home.repair, wrote:
You didn't see that coming? Did you think the bulbs were rated for 8
volts more than what the original transformer was able to supply? :)
Instead of continuing to replace the 16volt transformers that
obviously don't have enough amps to do the job you're asking of them,
why not get a higher amperage but same voltage one instead? That way,
you don't burn any bulbs out or anything else up by sending too much
voltage to the components.
If the door bells are electromagnet based, you're doing them harm
too, but, not as quickly as you are the bulbs. If they're electronic
chimes, you best hope they are variable input voltage style, or, you
will burn one or more of them out soon enough, too. 8 volts or so
(not really counting for possible voltage drop due to wire length or
loads) may not seem like much of a difference to you, but, it can be
to the components that are being fed by that transformer.
I'm sure they are brighter than before, and, no doubt, generating a
bit more heat than previously, too. Funny how that works, isn't it?
/sarcasm. Clare provided you sound advice and even offered
transformer spec suggestions. FWIW, I'd suggest you take their advice
and follow it. Before you burn out more bulbs and/or the doorbell
components along with the bulbs.
Oh, and next time you decide to play with electricity, consult with
someone who understands the concepts better than you obviously do.
Don't bother responding that you know WTF you're doing because you
can reconnect wires, either. If you did, you wouldn't have toasted
the second, third, etc, transformer or replaced it with a higher
voltage one thinking that's what the issue was. I don't apologize for
my harsh tone in this post, because, it might save your life one day
if you remember how much of a 'dickhead' I was towards you next time
you decide to play with electrical circuits.
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