Contact Information
Web Site Search
Intercom Repair Request Form
NuTone IK15 & IK25 DoorCom Systems
Vintage NuTone Intercom Catalogs

Main | Final Testing of a Rebuilt NuTone IM4006 Master Station »

NuTone Model IM4006 Radio Cassette Intercom

Exciting news for the music lover and those with discriminating audio tastes! The finest audio you can imagine in a home-communication system is yours. . . from NuTone.

The IM4006 was introduced in 1986 and quickly became the most popular music intercom system that NuTone had ever made. The IM4006 was based on a new platform that began with the IM3003 in 1984 and that platform design was used through the end of 2006.

The IM4006 featured a cassette tape recorder that doubled as a family message center, allowing any user to leave a voice message for family members to listen to.

The IM4006 was the very first model of music intercom to feature a true digital radio tuner with electronic scan tuning, 10 programmable radio station presets and a digital clock and radio frequency readout.

Since the IM4006 is a 6-wire system, it features “hands-free” reply intercom functions and remote stations including a “Privacy” button to block unwanted listening into that room.

The standard IM4006 was designed to accommodate up to 9 remote stations, but with the IA410 Expansion Kit, the maximum number of remotes increased to 20.

The IM4006 was a very reliable system right from the beginning with the exception of a new type of wire that NuTone introduced for the IM4006. The new wire was NuTone's IW6R, the “R” stands for ribbon.

This ribbon wire was a attempt to make the installation of the IM4006 easier and quicker, the exact opposite is what really happened.

The original IW6R was a flat, 6-wire ribbon cable that had solid wire inside the ribbon. The insulation that made up the ribbon was thin and it could be easily damaged during the pre-wire of a new home.

Installers were accustomed to IW6 cable, which is strong and pulls easily through pre-drilled holes in construction framing. IW6R ribbon wire is almost 1 inch wide and unless the pre-drilled holes are extra large, the edges of the cable will be damaged when the cable is pulled through the holes. It was not uncommon to have several cable runs in a single house have damaged wires.

The IW6R used crimp-on connectors that were included with each remote speaker. These connectors were to be crimped on to the ends of the IW6R cable when the system was trimmed out.

Installing the connectors required reading the directions (not a popular thing for installers to do) and some amount of finesse in preparing the cable and crimping the cable (also not a popular skill with installers).

A well-done intercom trim-out could be completed in half the time compared to using cable with indivisible wires.

Another feature that made the IM4006 so popular was starting in 1986, NuTone offered a “Life-Time” Warranty on all of their intercom systems. This warranty included Parts, Labor and In-Home Service for any problem with the systems. I personally performed many hundreds of warranty calls which were just to replace crimp-on connectors.

The IW6R cable was modified to use stranded wire in the cable which eliminated the potential of the crimp-on connector not making a good connection to the wire. It did not solve the “installer skill” issue. Around 1991 NuTone abandoned IW6R cable and the newly revised IMA4006 went back to standard IW6 cable with its individual wires fastened to screw terminals.

While NuTone choose to only label this model as the IM4006 and later the updated version became the IMA4006, there are actually 3 different variations if you look at the circuit board changes from 1986 through 1996.

The breakdown for the 3 variations is roughly:

1986 – 1987 Original Version Boards

1988 – 1991 1st revision of amplifier/power supply, intercom control and master control boards.

1992 – 1996 2nd revision of amplifier/power supply, intercom control, master control, terminal board and function selector boards.

There is not a lot of interchangeability between the 3 variations listed above. Intercom control boards can be used on all 3 variations, but amplifier/power supplies and master control boards cannot, and should be considered as “sets”.

The boards and assemblies that remained mostly unchanged throughout its production were the radio tuner, memory/display, cassette player & pre amp boards. These parts are interchangeable on all versions made from 1986 through 1996.

(The IM4006 is a complicated unit with many circuit boards and interconnection cables)

See all of the IM4006 pictures

Ask a question

Make an Intercom Service Request


Reader Comments (49)

I have an IM-4006 that along with the constant humming sound, the outside intercom door chime does not work anymore. I am a consumer and would rather have this fixed via the life-time warranty. Do you have any points of contact for nu-tone on the warranty?

August 4, 2013 | Unregistered CommenterDarrin W. Wargacki

Hi Darrin,

NuTone discontinued the Life Time Warranty program (MPP) at the end of 1999 and ceased authorizing repairs under the program in 2009. This is mainly due to the way the warranty program was written. Simply put, it covered the equipment from manufacturing defect, to the original purchaser for as long as they lived in the home. The warranty never covered normal wear and tear. You can see NuTone's point, your IM4006 is between 17 and 27 years old, any problems with the equipment is certainly well beyond the "manufacturing defect" period.

As a NuTone Authorized Service Center, we have always performed in-warranty repairs on NuTone's behalf and I have repaired hundreds of IM4006's covered by the MPP Warranty. Unfortunately none of the MPP products are eligible any longer.

I will contact you directly on Monday to discuss the problem with your system.


August 4, 2013 | Registered CommenterCindy & Christopher

Our im4006 needs repair/replacement but we are in Denver, any suggestions?

August 10, 2013 | Unregistered Commentersb

Hi SB,

Please fill out an Intercom Repair Request Form (under the Navigation Header) and once I receive it, I'll contact you about send your IM4006 for repair.


August 11, 2013 | Registered CommenterCindy & Christopher

The diode and transistor failure likely occurs when a nearby lightning strike induces a large voltage into the relay coil - one that exceeds the breakdown voltage of the diode and driver transistor. The only remedy is to install a spark gap or Transorb across each relay coil.

August 24, 2013 | Unregistered CommenterAaron

Hi Aaron,

While your idea is probably correct for some installations, it does not likely apply to installations I see locally. We do not have the type of lightning storms in California that occur in other parts of the country.

August 25, 2013 | Registered CommenterCindy & Christopher

We recently purchased a home with this intercom and unsure if it works or not. Most importantly we need to determine if the door bell still works. Is there a more modern version that we could upgrade to? Trying to find any info available. Thank you.

September 11, 2013 | Unregistered CommenterDoug

Hi Doug,

The IM4006 or IMA4006 can be update to the new NM200 system. Because of the age of your system you will need to update not only the Master Station but all of the remote speakers also. All of the new equipment is smaller than your existing equipment, so you can use the adapter frames that NuTone makes or have the openings in the walls made smaller.

If you would like a quote for new equipment, Please fill out an Intercom Repair Request Form and once I receive it, I'll contact you to discuss the updating of your system


September 12, 2013 | Registered CommenterCindy & Christopher

I bought a home with this system in place. Unfortunately, during renovations the construction guys took out all the speakers in the room. I have them installed now. However, I can't figure out how to use them. The door bell is connected to the system as well.
Do you have a manual that you can send me?

October 8, 2013 | Unregistered CommenterJimit

Hi Jim,

You can download a copy of the Owners Manual from the Free Manuals section on this site.


October 9, 2013 | Registered CommenterCindy & Christopher

Bought this house that has a complete IM 4006 installed (command unit, door bell, intercom, door chime, inside and outside speakers but unfortunately system starting humming then buzzing then will not turn on at all. Do you think this can be replaced or repaired? Any idea of cost? Thank you.

October 27, 2013 | Unregistered CommenterLouis

Hi Louis,

Yes, your IM4006 can be repaired. Please fill out an Intercom Repair Request Form (under the Navigation Heading) and once I receive it, I'll contact you directly about the problem with your system


October 28, 2013 | Registered CommenterCindy & Christopher

How do I disconnect it? do you have a manual?

March 3, 2014 | Unregistered CommenterKen

Hi Ken,

You can download a free copy of the Installation Manual by using the link under the "FREE MANUALS" navigation heading. If you read the manual and follow it backwards, you should be able to disconnect and remove your Master Station. If you have additional questions, please email or call me.


March 3, 2014 | Registered CommenterCindy & Christopher

I have one of these systems in my home. Do you know the gauge of the conductors in the ribbon cable?

March 21, 2014 | Unregistered CommenterDave

The wire in the IW6R Ribbon Cable is 22 gauge


March 21, 2014 | Registered CommenterCindy & Christopher

The IM-4006 unit I have is pretty old. like ~26 years. Is it possible to disconnect only the tape section. The noise (even when I am not using it) is annoying. Would like to keep the door bell that the unit is connected to.

May 21, 2014 | Unregistered Commenterjay

Hi Jay,

If the cassette player is making noise all the time, it means that it is running continuously, which is a problem and is wrong.

It is possible to disconnect the power to the cassette player. You will need to call me so I can explain how to do this.

You can also consider having your IM4006 rebuilt, it is a very good model and in many respects it is better than the models that are made today


May 22, 2014 | Registered CommenterCindy & Christopher

I have static radio out of tune!
How do I find a repair person who is update on the info u shared above!?
Chris O

June 1, 2014 | Unregistered CommenterChris o

Hi Chris

We can repair your Master Station for you.

Please fill out an Intercom Repair Request Form (under the Navigation Heading on the right-hand side of the page) and once I receive it, I'll contact you directly about the problem with your system


June 1, 2014 | Registered CommenterCindy & Christopher

Where can I find an installation manual for a nu-tone im4006 radio intercom system?????

July 15, 2014 | Unregistered Commenterbarry

Hi Barry,

Installation Manuals are located under the Main Heading "FREE Manuals and Installation Guides" which is on every page of this site. All Manuals and Guides are FREE downloads


July 15, 2014 | Registered CommenterCindy & Christopher

I have the Nutone Music Intercomm IM-4006 Series. My electronic door chime button will not stay in in its place. The back part that holds the button in its place when you push on the button is apparently broken or has a crack in it. Is there a way that I can just replace the button and and button holder?

July 17, 2014 | Unregistered CommenterDonald Wales

Hi Donald,

It's not uncommon for the locking tabs on the back part of the push button to break off because the plastic becomes brittle over time.

We have genuine NuTone Door Chime Push Buttons and you can contact our office to order one.


July 17, 2014 | Registered CommenterCindy & Christopher

The two lower panels on the IM-4006 system that cover all the individual speakers have a very poorly designed hinge which 3 out of the 4 have cracked apart. Do you know where I can get replacement hinges or if there is a retrofit hinge to replace? Thanks Kevin

July 22, 2014 | Unregistered CommenterKevin

PostPost a New Comment

Enter your information below to add a new comment.

My response is on my own website »
Author Email (optional):
Author URL (optional):
Some HTML allowed: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>