Help. Nutone door chime with Telechron clock.

[sarahperdue]

Hi everyone,

I just purchased this vintage Telechron clock Nutone door chime combination from eBay. The clock is working, but it has some dust and debris underneath the glass. The door chime was not working at all when I first tested it. Now, I have both solenoids working, but the back door plunger seems to be too short.

I would like to know how to remove the basil and glass to clean under it, how to repair the plunger on the back door bell, if it’s OK to lubricate the chime plungers with powdered graphite, and if there’s any maintenance I need to perform on the clock. I also need a new nut or whatever it called on the stem.

Thank you,
Sarah

 

[lowefficiency]

For photo #9, the plunger that seems too short, what does the back side (with the spring) look like when you pressed it through for the photo?

 

[rp2813]

Very Cool!

Sarah, you may already know this, but in case you don't, the back door plunger typically only strikes a single chime bar as opposed to the front plunger, which strikes both bars.   You can see in picture #7 that the rear (presumably) plunger has a plate that prevents it from striking the "top" bar in the picture.

 

So, if the rear chime only strikes once, that's normal.

 

I've read on doorbell sites that you should never lubricate the plungers.  Just clean them, with a green scrubber or perhaps steel wool, and I would think it best not to use any water or other cleaners.  All you need to do is get them smooth again.

 

Now, if the rear chime isn't striking at all, then yes, there's a problem that the cleaning may or may not resolve.  

 

The clock appears to be secured by the two zip nuts shown in picture #5.  That seems like an odd arrangement, but the zip nuts seem to indicate that the screws they spin onto are stationary.   If that's the case and you can remove the clock assembly, there should be tabs on the back of the bezel that you can carefully bend up to remove it, along with the glass. 

 

Be very careful about cleaning the face of the clock.  If just dusting with a fine brush will clean it, that's all you should do.  Resist the temptation to use any cleaner or to rub the painted surface in any way or you will likely cause irreparable damage.  You can of course clean the glass with Windex or whatever.

 

The time adjusting rod has a reverse thread.  A junker Telechron or GE clock that has the nut on it would probably be your best bet for replacing the one that's missing on your NuTone. 

 

Do you have a recessed clock outlet where you plan to mount this rig?  If not, you should consider one.  It's an interesting concept to have 120v powering the clock and I presume the chime transformer, which eliminates the need to place an external transformer in some mystery location, as is often the case with doorbells.  I like it!

 

[sarahperdue]

More details

Dave,
I will take another picture of the back of the plunger. When activated by the doorbell button, it travels all the way, almost flush with the solenoid, and the spring is completely compressed. It sticks in the forward position and the front end barely activates the chime. The tip on the plunger for the rear is much, much shorter than the tip on the front chime. Decreasing the length of travel between the back of the plunger and the stop doesn't work because the problem is that the tip does not move forward far enough to contact the chime. I will add a photo.

Ralph,
I have also read that the plungers and solenoids should not be lubricated with oil but a small amount of graphite powder might be OK. The solenoids are spot welded to the frame of the chime, and the resonators are attached by bolts that run through the chime (via a grommet) and into the resonator. There isn't room to loosen or reattach that fastener. Presumably it was added before the end caps of the resonators were installed.

I'm thinking that I should separate the rear solenoid from the body of the chime. Then I can polish the plunger and interior of the solenoid and replace the tip with something longer. Even with the plunger fully extended, it barely makes contact with the bell. I've read that they were made from wood or hard plastic. If everything was attached by screws or nuts and bolts, I'd disassemble the whole thing, polish the chimes, plungers and solenoids and replace the grommets. Since it's not, I'm going for only the necessary repairs.

I plan to use a very fine brush on the face--I think a camera lens blower brush is perfect for the job--and windex on the glass.

Interestingly, the clock is designed to run on the low voltage circuit. It is powered by the output of the doorbell transformer. Check the close up of the service tag. So that addresses the fire risk issues that are attributed to the Telechron clocks.

But I do have several other Telechron clocks that run on 120v. How much should I worry about the fire risk?

Thanks, Sarah

 

[rp2813]

Sarah, it sounds like you've done your research and homework, and know how to proceed.

 

I did study the service tag on the clock and when I saw the cycles and watts, I just assumed -- based on the relatively heavy duty 120v leads connected to the coil, that the clock ran on 120v even though 16v was indicated.  It's definitely an unusual level of power for a Telechron rotor.  I would guess it's not the typical H-3 model.

 

I'm confident you'll have all parts of this chime working properly in fairly short order!

 

 

 

 

 

[oliger]

You should lubricate the clock. It will run with less resistance and less heat.
If you give a diagonal view, I could tell you how it should-ought to come apart.
Just any general oil on each gear plus the top and bottom axis. Use a q-tip to apply.

There is a way to lubricate the rotors by heating them up in an oven and then submerging them in oil, although not always needed.

I would assume that the two black screws near the top would get the motor out. I am unsure since I cannot see the other side.

 

[sarahperdue]

Adventures in clocks and bells

I was testing it this morning when one of my wires came loose and crossed. A quick, small spark and everything stopped working. After troubleshooting, I determined that the transformer was blown. The status of the clock and chimes was unknown until I replaced the transformer--which I did. I followed David's (Turbokinetic) advice and installed an inline fuse. Everything works fine.

Tomorrow, I'm going to remove the back door solenoid and work on it. It's packed up for the trip--the right tools are at the country house.

Jon, I'll unpack and take more pictures next week. I will look forward to more information about lubricating it then.

I love the smooth sweeping motion of the second hand.

Sarah

 

[ozzie908]

Years back we had a tubular doorbell

And it used to struggle to chime after a while it was determined that there was no issue with the plunger or the solenoid but it was the spring had become too weak to fling the plunger against the tube, So it was repaired with a new spring with a bit more gusto and it carried on ding donging till it was removed and replaced with a new door bell when the porch was built.
Hope this gives you something to try out?

Austin