Simple Wiring Diagram for 2 Video Doorbells (Front and Rear) + 1 Chime + 18v transformer

[Powercar]

I have two doorbells connected to a mechanical chime. When I turn on both power kits both video doorbells stay active. However, the mechanical chime does not ring. But if I turn off one of the power kits the mechanical chime will work but one of the video doorbells will stop working eventually because it is not getting power. Do you have any ideas on how to fix this issue?

[StephenB]

---

@Powercar wrote:
I have two doorbells connected to a mechanical chime.

One connected between F (front) and T (transformer), and the other connected between R (rear) and T (transfomer)???

[Powercar]

That wiring is what I have plus a power kit on both.

[StephenB]

---

@Powercar wrote:
That wiring is what I have plus a power kit on both.

---

Ok, that is correctly wired then.

What are the voltage (V) and power (VA or A) specs for the transformer?

[Powercar]

The voltage says 16V and it looks like it says 10VA.

[StephenB]

---

@Powercar wrote:

The voltage says 16V and it looks like it says 10VA.

---

That should be enough but it is at the bottom end of the spec.  Your symptoms suggest there isn't quite enough power being delivered, so you could try replacing it with a 24V model that also has a higher VA rating.

Exchanging for AVD2001s might also be worth considering.  They don't need as much power (and don't use the power kits), because they are trickle-charging from the transformer.

[Powercar]

I have now switched the transformer from a 10VA 16v to a 30VA 16v and the doorbell is still not ringing.

[Powercar]

Here is a diagram of my wiring:

[StephenB]

---

@Powercar wrote:
I have now switched the transformer from a 10VA 16v to a 30VA 16v and the doorbell is still not ringing.

---

Your wiring is correct, and you certainly have more than enough VA.  

Are the symptoms the same (one doorbell+powerkit works, but both together don't)?

Do you have the ability to measure the voltage (either at the doorbell, or at the chime)?

BTW, does it matter which doorbell/powerkit is disconnected?

[Powercar · Accepted solution]

Thank you for all your feedback. After about two weeks, everything has continued to work without any problems the resolution was using a 16v 30va transformer.