Possible cause for light switches no longer turning on after smart dimmer install?

[shomel]

I installed a smart dimmer switch in my dining room, which worked fine. The next day, I installed the same type of switch in my kitchen. Not only did it not power on, I noticed that the light switch in the dining room no longer turns on, and that the light switch in my foyer no longer works either (an old switch, not a new install). These are all single-pole switches. The three-way switch in my hallway, which is on the same circuit, still works fine. I tested the power to the circuit breaker and the power to the wires in the switch box, and everything has power. The light switch in the foyer is illuminated to be seen in the dark when the switch is off, and that light in the switch still turns on. The circuit breaker was off the entire time during install, so there was no evidence of it tripping. There's a GFCI breaker in the kitchen, which works fine. All outlets are working. Any idea what the problem is? Thanks in advance!!

 

[Pete999]

I installed a smart dimmer switch in my dining room, which worked fine. The next day, I installed the same type of switch in my kitchen. Not only did it not power on, I noticed that the light switch in the dining room no longer turns on, and that the light switch in my foyer no longer works either (an old switch, not a new install). These are all single-pole switches. The three-way switch in my hallway, which is on the same circuit, still works fine. I tested the power to the circuit breaker and the power to the wires in the switch box, and everything has power. The light switch in the foyer is illuminated to be seen in the dark when the switch is off, and that light in the switch still turns on. The circuit breaker was off the entire time during install, so there was no evidence of it tripping. There's a GFCI breaker in the kitchen, which works fine. All outlets are working. Any idea what the problem is? Thanks in advance!!

No Nuetral ? maybe

 

[shomel]

No Nuetral ? maybe

Thanks for your response. I wired the neutrals as well.

 

[Pete999]

Thanks for your response. I wired the neutrals as well.

What voltage are the switches rated at and what voltage do you have at the switches?, being in the US I xould be completely off track with my questions, maybe one of the Forums US members will be able to help sorry I can't help any more Mate, good luck anyhow, try PMing Megawatt he is always helpful.

 

[westward10]

Show a pic of the wiring at the switch.

 

[freddo]

I assume you have rechecked all the connections at the new switches and in the switch boxes too see that no wires have come loose or broken off at a terminal or joint ?

 

[Lucien Nunes]

If there is definitely power at the hot wire in the two non-functioning switches, I agree with Pete that the most likely cause is that the neutral for those lights passes through the dining room switch box and working in that box has broken the connection. In this case, both hot and neutral at the non-functioning lights will appear to be hot relative to ground.

 

[shomel]

If there is definitely power at the hot wire in the two non-functioning switches, I agree with Pete that the most likely cause is that the neutral for those lights passes through the dining room switch box and working in that box has broken the connection. In this case, both hot and neutral at the non-functioning lights will appear to be hot relative to ground.

That definitely seems to be possible. Got a new voltage tester and I'm getting inconsistent results. There at times seems to be power going to the neutral and load wires, now even when the breaker is off. I think it's time to call my electrician.

Thank you all so much for your help! Be safe out there!