Model # 121AC-A

Internet #100626843

Heath Zenith Wired Door Chime Transformer-DISCONTINUED

Discontinued Heath Zenith

Wired Door Chime Transformer-DISCONTINUED

store icon Loading Buying Options...
package icon Loading Buying Options...
Sorry, but we ran into issues loading these options. Please try refreshing.

Frequently Bought Together

Product Overview

The 121AC is a wired door chime transformer. Features a 120VAC input and 16VAC-15VA output. The transformer is a lock nut type.

  • Replacement Low Voltage Hardwired Transformer
  • UL Approved
  • For use with any wired door chime
  • Requires 20 AWG Minimum



Product Depth (in.)
Product Height (in.)
Product Width (in.)


Accessory Type
Door Bell Or Intercom Type
Door Bells
Electrical Product Type
Door Bell Accessory
Product Weight (lb.)

Warranty / Certifications

Manufacturer Warranty
1 Year

More Products With These Features


Customer Questions & Answers

Is this what I need?

I am trying to replace a transformer we removed. The one we removed is EM57580. The other markings are: 122C Class 2 Not Wet Class 3 Wet Class 2 LR90668 Line 120V 60Hz Load 16V 10VA. Will the model # 121AC-A work as a replacement part?
Asked by: Anonymous
Correct, the 121AC is capable of supplying more power (15VA) than the 122C (10VA), but the unit it is powering will only draw the amount that it actually needs to operate.
Answered by: HeathCo
Date published: 2015-09-17

Is the Model #121AC-A Transformer the correct transformer for the DESIGNER Wired + Wireless Doorbell?

Asked by: Anonymous
Model 121AC-A will work with the Designer Series doobells. DW-122 will also work fine.
Answered by: HeathCo
Date published: 2015-09-17

I replace twice the transformer (blowout)burn

why no support 6 bell is anything wrong on bells because the wire are too old or is possible use other transformer you ken help me thankyou.
Asked by: Anonymous
Please call our technical service department at 1-800-858-8501 and they can help you with some troubleshooting options.
Answered by: HeathCo
Date published: 2015-09-17

what is the continous current rating on a doorbell transformer? (Model # 121AC-A)

Asked by: Anonymous
Transformer model 121AC-A is rated for 16VAC – 10VA. The 10VA power rating is a continuous power rating. That would mean that the continuous current that could be drawn from this unit is 15VA/16VAC=0.9375A.
Answered by: HeathCo
Date published: 2015-09-17
  • y_2017, m_7, d_17, h_6CST
  • bvseo_bulk, prod_bvqa, vn_bulk_1.0.0-hotfix-1
  • cp_1, bvpage1
  • co_hasquestionsanswers, tq_4
  • loc_, sid_100626843, prod, sort_[SortEntry(order=NUM_ANSWERS, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING), SortEntry(order=LAST_APPROVED_ANSWER_SUBMISSION_TIME, direction=DESCENDING), SortEntry(order=LAST_APPROVED_ANSWER_SUBMISSION_TIME, direction=DESCENDING), SortEntry(order=BEST_ANSWER_FEEDBACK_COUNT, direction=DESCENDING), SortEntry(order=POSITIVE_ANSWER_FEEDBACK_COUNT, direction=DESCENDING), SortEntry(order=NUM_ANSWERS, direction=DESCENDING)]
  • clientName_homedepot
  • bvseo_sdk, java_sdk, bvseo-3.1.1
  • CLOUD, getContent, 28ms

Customer Reviews

Wired Door Chime Transformer-DISCONTINUED is rated 5.0 out of 5 by 5.
Rated 5 out of 5 by from Door chime transformer I have personally installed over 500 of these transformers and have found them to be outstanding in every way.
Date published: 2009-04-07
Rated 5 out of 5 by from Solved the problem! Installing a second door bell to an existing one I found that I needed a larger transformer output. To the Home Depot website I went and found exactly the one I needed. Ordering was easy over the phone (web-site billing portion down at the time) and it was shipped immediately and arrived in a reasonable number of days. The old as well as the new doorbell ring through there whole chime cycle and now we can hear the bell when in the family room
Date published: 2011-08-31
Rated 5 out of 5 by from Good product I called the mfg before ordering and got the details on how to install and confirmation it would do the job. It did just as they said and was easy to install. Good Product
Date published: 2013-07-16
Rated 5 out of 5 by from Transformer Easy install (hard to put it in wrong) . Fit exhisting electrical box. Took about 15 min to do the job.
Date published: 2011-01-25
Rated 5 out of 5 by from 15 watt wired door bell transformer This product works great and what you need to operate two doorbell chimes.
Date published: 2011-01-22
  • y_2017, m_7, d_17, h_13
  • bvseo_bulk, prod_bvrr, vn_bulk_1.0.0-hotfix-1
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_5
  • loc_, sid_100626843, prod, sort_[SortEntry(order=RELEVANCE, direction=DESCENDING)]
  • clientName_homedepot
  • bvseo_sdk, java_sdk, bvseo-3.1.1
  • CLOUD, getContent, 45ms