How can I Monitor my Furnace?

So I woke this morning to my Furnace not igniting. I didn’t realize it (Other than it being colder in my house than usual) until I turned the heat up and the damn thing did’t ignite. It then tried to vent all of the gas in the chamber which made my upstairs smell like gas.

Is there anyway to monitor my furnace so I can make sure it’s working? In this case the pilot light won’t ignite, but the ignitor seems to be getting power. so a zwave switch may not work.

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Does your furnace have a status light? Mine detects when this happens and goes into lockout mode and the light flashes in groups of two to indicate this state. I’m sure its possible to connect into that circuit board somehow to detect this. Not for the faint of heart, but doable.

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I’m curious about this too as I had a similar issue with mine a while back. You can always monitor inside temperature and alert if it doesn’t rise when expected?

Otherwise I think most of the hardware out there is not engineered to monitor these types of things. Maybe some energy usage monitor inline with the furnace power to the breaker box? Mine uses fuel oil so that’s the only way I can think of that I can get in there and know that it’s running.

Unfortunately it doesn’t. I have a furnace guy coming out today, so I am going to ask him if he knows of anything. It would be nice to have a way to tie this into smartThings.

It’s below 0 today. This always happens on the worse day possible.

This is a great idea, I too woke up one morning to 50 DegF, my furnace had failed to fire as well. Long story short the flame sensor was dirty. It would be awesome to somehow report the error codes my unit spits out to me. My unit shows a number on a seven segment display to report the failure. Would be cool to get this into arduino and in turn ST… No idea how… but cool…

cool is by far the easiest. :wink: Just send an alert if temperature fails to reach a minimum at an expected time on any networkable temperature sensor in any appropriate location. You could also trigger a still camera to take a picture of the display panel.

Personally, i leave the furnace itself alone.


So it turned out to be our blower motor. I guess if the connected thermostat has a state of when the fan should be active, you could put a sensor on the motor. In the case of nest it takes 15 seconds for the fan to kick in. If the fan doesn’t kick in 15 seconds after state change, send a message.

I am still not sure how to monitor for ignition…

Maybe check the temperature at the stack. Technically it should be the hottest spot.

Yea, that wouldn’t be hard. I just know there’s a wealth of information that could potentially be provided that would be nice to know.

Ecobee thermostats have this kind of monitoring built into its email notifications. I used to have an EcoBee before my Nest and this is a feature I missed. It actually saved my house from freezing over last winter when the temp outside dropped below -30 Celsius and I had a pressure switch failure while I was away on holidays. I was able to notify my neighbour and contact my HVAC contractor to come and fix my furnace so my house wouldn’t freeze over.

This was the example email notification I received from ecobee:
"Huy Nguyen, you have an alert message from ecobee for thermostat: XXXXXXX6886:

There maybe a problem with the Furnace. For the past 2 hours the thermostat has been calling for heat, but the room temperature has decreased by 1.6C. Contact your service contractor JD Swallow Heating Contractors INC at 613 822 7974"

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Maybe someone can right a smartapp that would mirror this type of notification.

ST has that built in. If you look up monitor for freezing and point it to your thermostat or any temperature sensor it will notify you. I have it setup for my Aeon Multi in my basement where my pipes are. I saw a notification and panicked luckily the sensor was just freaking out for a second.

Yeah I have that notifcation for temp below a certain threshold setup as well. But what I liked about the ecobee was that before it gets to a extremely cold temp it warned me. Ie Thermostat is trying to heat but the temp has gone down from when the thermostat called for heat, instead of up. This would allow me to deal with it promptly instead of waiting until its near freezing.

Yea I do like the idea of the thermostat calling out and saying it can’t do it’s job. As I said previously in my post mine failed on me one early morning and it was no fun, I was more worried about my infant than myself. Maybe I’ll build something into my Ecobee Clone SmartApp I’m making.

…I’m still convinced I get more functionality with z-wave / zigbee equipment… I’m making a test with simulated devices now, haven’t purchased anything.

Very interested in this discussion…

We have a steam system with boiler. When the water level gets too low, a low water cutoff kicks in (pictured below) and the boiler stops boiling water until I manually refill the system. During the winter this has been happening every 3-5 days! And it always seems to happen at 3am. (Why do these things ALWAYS happen in the middle of the night??) We’ll wake up to a freezing house and I’ll have to scurry down to the basement to refill the system.

I’ll admit that I could make refilling the system part of my nightly ritual, but that’s no fun and we have busy lives.

Right now I’m using the “It’s Too Cold” Smartapp to alert me when the temperature drops below my thermostat’s threshold. This works during waking hours, but not really in the middle of the night. I tried to set up an IFTTT recipe to call my phone when the temperature drops to a certain level, but it has never worked. Not sure why. Regardless, these alerts only work when the temperature is already way too cold. I’d love a warning like the Ecobee gives so we don’t have to freeze our butts off.

The low water cutoff is, as I understand it, just a simple switch. When the water is low, it shuts down the boiler. I’d love to hack something together, attaching this to a z-wave switch or something so I get an alert when the cutoff has been activated. Perhaps using a door sensor and putting it on the circuit between the cutoff and the boiler? As someone said above, it’s not for the faint of heart. I’d have to get an electrician or HVAC person.

Wow blast from the past, I grew up with one of those, I would be the one to run down and fill the water supply, then when it kicked on I’d get black soot under my nose… Probably not good.

Ha. No soot. Thankfully the boiler is only a few years old. The house is 1926.

If anyone’s interested, I found a way around the issue with IFTTT. I created a virtual switch and named it “Phone Call”. Then I configured the “It’s Too Cold” Smartapp to turn on a heater when it gets too cold and selected the Phone Call switch as the heater. Then I created an IFTTT recipe that will call me when the Phone Call switch turns on. This works well. Seems switches are more reliable than temperature sensors on IFTTT.

While I was at it, I also set up an IFTTT recipe to call my phone when my alarm goes off. Gives us an extra layer of notification in case we don’t hear the siren or don’t see the push notification. Same procedure as above. IFTTT sees the alarm as just another switch.


Check out this monitor:
It monitors a signal and sends a text notification to your phone.