The Client has a 2yr old Nutone intercom system.
the Door station has a standard Doorbell button. No Light.

When you press the button it rings the intercom system.
there is a traditional doorbell Bell as well. when i hookup the wires from the 24vac Bell to the incoming dry contact both don't work.
so i was thinking about
[Link: elkproducts.com]
however this is 12-24vDC not AC.
therefor I am looking for a similar product in AC.
Basically change a Wet Contact closure to a Dry.

More details.
How many wires go to the door? Does "door station" mean there's a speaker at the door? Does intercom audio run over the wires going to the door? At first I thought you were saying that the Nutone runs on DC but rereading, I'm not sure.

What does the Nutone manual/tech service person say about this? What are the model numbers of the door station and the main chassis?

There's an existing working door station and an existing working chime that runs on how many volts AC?

2 conductors for the door bell.
|Does "door station" mean there's a speaker at the door?
Yes the other 2 from the Main station runs the speaker/mic.

|Does intercom audio run over the wires going to the door?
Yes thats what an Intercom means?

|At first I thought you were saying that the Nutone runs on DC but rereading, I'm not sure.
Its A Dry Contact. That mean 0 or no voltage.



I have a email in to them but they no longer make the product.
Nm200wh


same question different way.
Doorbell to Nutone=Dry
Doorbell Bell=24VAC

So, four wires.

Yes. So many details were omitted that I was just being sure.

I ask about "the Nutone." You respond "it's a dry contact."
I'm having trouble following you.


See if this helps. [Link: nutone.com]

Are you sure the doorbell chime requires 24VAC? Most doorbells we install only require 16VAC. I am sure the 24VAC wouldn't hurt the chime, it just needs enough voltage to power the coil but I would check this as a 24VAC transformer may be outputting up to 30VAC. I have installed multiple 16VAC transformers that output at 19+VAC.
Are you certain you have the door bell chime wired correctly? If you connect both the Chime and Nutone station together and neither work, this may be a wiring problem and not a compatibility issue.

I might have the answer. It seems the dry contact can be used to ring the doorbell.

I just read through the document for which I provided a link in Post 4. This sentence from near the end of the installation instructions of any help:

Just in case this is not clear, "24 Volt/2 Amp switch" doesn't mean there's 24 volts anywhere in the system. It means this switch is rated to switch up to 24 volts at a maximum current of 2 Amps.

The ordinary non-lit doorbell button is a dry contact. Doesn't that mean you can use this unit's dry contact so that pushing the intercom button rings the doorbell? As I said, the instructions aren't clear enough to think things through... is that dry contact a part of the intercom push button, or is it a separate switch?

From reading the user instructions I interperate the 24V/2A dry contact as a user controllable output and would not be triggered when the door station push button is used.

From the user manual

You were on the right track with Elk, but didn't have the right product.  Look up the Elk 930 which is a doorbell detector.  Doesn't change the operation of the traditional chime and provide a contract closure output.

I've used them a number of times over the last 15 years (including one at my house) and have never had one fail.

That might be if dry contact didn't mean something totally different. This Wikipedia response has it:


A switch, connected to nothing, is a dry contact. No voltage. When you attach a couple of wires to it and mount it in a product so it can be pushed as a button, it's still a dry contact. The intent of this is to give you a place to connect two wires to make something happen. These two wires have to present a voltage to go through the dry contact.