Working around zwave dry contact relay when there is no power

We have a fireplace that yesterday was on a light switch to turn it on and off. It even has a battery pack (D batteries), so if the power goes out, we can still use the fireplace.

This morning I set this up: only to be able to turn on/off the fireplace via Google Home AND continue to use the wall switch. We do not plan to use any automations at all with the fireplace.

The new setup is working great! The only issue I see is that if the power goes out, we have no lost the ability to turn on the fireplace with the light switch. I really liked this feature even though we rarely lose power. We live in central Indiana, out in the middle of nowhere, so having the fireplace as a backup emergency heat source is a really good idea.

The only thing I’ve been able to come up with so far is perhaps routing the trigger around the dry contact relay with a simple light switch. So if the power goes off, we pop the fireplace cover off, flip that switch, and we’ll have the fireplace control ability restored, like we could yesterday. I’m not sure my wife will go for this, though (if I’m not home). She won’t be excited about taking off the cover of the fireplace.

What would be great is if there was a switch that routes around the dry contact relay, so that if there was no power, it would be enabled automatically, restoring our ability to use the switch on the wall to turn the fireplace on.

If there was a small enough battery backup, I could put that under the fireplace, but that just sounds dangerous. I’m probably just nervous about nothing, but also I was unable to find a UPS that would fit, so I guess the point is moot.

Perhaps I could just make the wall switch the override. So, if the power is out, it can still ignite the fireplace. Of course this means I’d want to just use Google Assistant or Smartthings app to control the fireplace for normal operation, and only use that wall switch when the power is out. Does anyone see any issues with that?

Have you checked your local township to make sure that they allow for remote control from further away than about 20 feet?

Many jurisdictions restrict fireplace control (unless it is one of those really fancy fireplaces which meet code requirements for a gas heater with thermostat) to line of sight. That means as soon as you allow for smartthings or echo control, you are violating the safety code. It doesn’t matter if you never intend to open up the app while you are 10 miles away at the office and turn on the gas fireplace: just the fact that you could is a code violation.

And when you install something which is a code violation, you can also void your homeowners insurance.

Smartthings does produce cloud glitches from time to time which can turn things on unexpectedly. You’ll find threads on lights randomly coming on or even the garage door opening. :scream: So the safety codes on gas fireplaces aren’t unreasonable.

Once you start setting up the bypass as well, you create additional possibilities for platform glitches.

So while I could imagine a couple of different ways to do what you’re talking about, only not using the method you’re describing, I want to first make sure that you have checked to see that any out of sight automation capability is in fact legal where you live.

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Thanks, I looked at other fireplace related posts in this community, but didn’t see these questions being brought up there, but I’m glad to know there are potential issues.

I searched for such a restriction for our township and found none.

You did get me thinking that I will setup an automation to disable the fireplace if no one is home, so if such a cloud glitch did come through, I’ll have it turn off immediately. Also, I may just set a timer to turn off the fireplace after 1 hour (or so), just so it never stays on too long. If we have not power, then all of the Smartthings integration would be disabled anyway, so if we have the fireplace on, we are flipping physical switches to enable it.

Most important thing will be to use the presence detection with Nest (we have smoke alarms all over the house to detect presence) to not allow the fireplace to run while the house is empty.


Hopefully you will find a moment to share your “couple of different ways to do what [I’m] talking about”. I look forward to hearing from you.

I have mines wired in parallel with the existing non “powered” wall switch. The fireplace existing fireplace switch works by making contact to the gas relay that works off of micro current. The pilot light provides enough micro currents for the switch to work. It’s works just like an open/close contact.

My fireplace also has a fan that is powered by 120v. It has a thermal coupler in the fan that turns the fan on after a certain temperature is reached. I put a SmartSwitch on the fan and then a dry contact ran in parallel with the existing switch. (Use the outlet inside of the fireplace that is turned on/off by the switch that provides electricity to the fan). The dry contact relay opens/closes based on if the outlet is powered or not. The dry contact is then ran to the same terminals as the old existing dumb switch.

(Issue) If someone turns on the fireplace with the old dumb switch, then you can not turn if off via the SmartSwitch.

However, this is the way it was previously…

(Smarts) If someone turns on the fireplace with the SmartSwitch then it works just like any other Smart Device.

(Bonus) If the power goes out, you can still use the dumb switch to turn on/off the fireplace. Since 120v is not part of turning on/off the fireplace. Only the fan needs 120v.

This is excellent, and was what I thought I’d end up doing except for your extra fan work, which I may do at a later date. Thanks for confirming and sharing so much detail. You’ve really been very helpful. :+1: :beers:

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