During an HVAC school training class something strange started happening with the COR thermostat on the wall that was worth sharing. The temperature kept rising for apparently no reason. Featuring Bryan Orr.
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I'm walking in the kalos guys just always standing around shooting the breeze wonder why he can't make any money around this place. My goodness, my goodness, gracious time just real man work, alright, so we're doing some cleaning up on the kalos training room and get this weird issue, and I'm is this kind of a boring video, but I want to just describe it. What's going on, we got our training room unit here and I was doing some training with some folks. I abused my training room equipment.
Let's just be frank about that, but we were fast cycling, the orange circuit, so in a heat pump, the orange circuit is the reversing valve circuit. This is a heat pump and I was kind of fast likely in showing shifting between heat and cool, so that I was doing and demonstrating the temperature change and the formerly artist, formerly known as the suction line, which then becomes the vapour discharge line in heat mode. But then, once I got it all back up and running, it's running and cool like it is right now it's it's running, okay, a little too cold outside. As you can see, it's 51 degrees outside.
So we shouldn't really be running in cool, but the temperature and the thermostat just kept rising at first. I didn't think anything of it, but I just kept going up but got into the 80s and just kept getting worse. So what I did is I disconnected the circuits one by one sort of a yellow and went through and then just kept reconnecting the thermostat and it would just stay high until I disconnected orange as soon as I disconnected the orange circuit, the OH circuit from this Thermostat then I put it back together and of course it would run in heat, but if the temperature would go way down, I can actually feel heat kind of radiating off of this thermostat support thermostat, it's radiating off of it more than a normally would, and so I disconnected this Obi from it and ran it, and then the temperature went down and then I left it disconnected - and I just bugged red to orange, on the outside check to the amperage on the o'the circuit alone, and it was very low. It wasn't.
It was like you know, point 1 amp, something like that, and then the temperature of the thermostat dropped again. So in the process of fast cycling, this thermostat, you know disconnecting and connecting orange you do get a little spike of amperage, because a reversing valve solenoid is an inductive loads magnetic load, and so you get a little ampere spike. I somehow damage the oh circuit. This o /b circuit in this thermostat I mean this is my working hypothesis.
Until we replace the thermos said, I'm not going to know 100 %, but that's my working hypothesis is that I damaged the circuit in here to the extent that, for some reason, within the thermostat, that circuit is now generating additional heat, which the thermostats cooking ups is Acting like additional resistance or, however, you want to say that that is causing additional heat in the thermostat. That's driving the temperature up, so we're gon na replace this thermostat. I hope we have another quarter laying around here somewhere we're gon na, replace it and see if the problem goes away. I should say: okay, so new core thermostat installed, and it is definitely not reading too high if anything, our humidity sensor hasn't acclimated, yet because it's definitely reading on the high side of what it really is here. But you can see we're actually two degrees below the indoor thermostat, so I think that's all there is to say about that. The issue was due to the rapid cycling of the orange circuit that caused damage to the circuitry, which caused it to overheat internally, which point of this video is that a lot of times with the thermostat displays isn't just impacted by the temperature of the wall temperature. Coming you know the convective gains coming in through the wolf there's a hole, so that's something to look for the temperature of the wall itself and then also the radiant that it's exposed to. So if this were, if they were sunlight or if this thermostat was exposed to some hot surface, like a hot wall on the exterior, but in this case it was generating its heat internally, and that was the problem.
So whenever you run into the through, you suspect it could be generating heat internally. The first thing would be to check the amperage on all the low-voltage circuits, maybe disconnect them one at a time and figure out which one's causing it and then, ultimately, in this case it just ended up being the thermostat itself. Alright, i'm brian with hvac school thanks for watching.
Thanks for posting this video. I have similar issue with the Cor thermostat.
Either it is too easy to be damaged or a design issue – the thermostat heats itself up so it's temp sensor is never accurate
Mine was working for 3 years – then failed in this exact this way. Thermostat was getting close to 90 degrees.
I'm on my third Cor (home owner) brand new system 4 years ago. Now looks like I've got the internal heating problem of the thermostat like in the video after finding it "offline". When that happens and I can verify good wifi I usually pull the thermostat and replace to reboot. What would be a good replacement anybody have recommendations? Thank you for your time….home owner ! Service area Barrhaven??
My COR thermostat display temp drops several degrees each time the air handler fan is turned on. This will cause the backup heat stage to engage.
Pretty sure this is a junk thermostat.
Cor stats freaking suck. Every one I've installed has had issues and now it's hard to get warranty replacements Service area Kanata??
COR Thermostats are worthless pieces of garbage and no one helps you with them. How about an owners manual you Toll Brothers Losers ? Hell Toll and COR are the experts at forcing people in to buying too high and DYI! Are you in Orleans ?
other issues with this thermostat is close to what you experienced. The actual display from this thermostat generates heat enough heat such that it increases the room temperatures sensing so that the thermostat will actually believe the home or building is warmer than it actually is bringing on the AC system and overshooting the temperature you will experience short cycling and overshooting nonstop the correction for this on this thermostat will be to disable the display from backlight on continuous to thermostat display only when touched
I think they are getting rid of the cor tstat, lots of ussues
I’ve had nothing but issues to compatibility with routers for WiFi use, to not being able to run them simultaneously with another cor in a different zone it’s weird ! Anyone else had issue similar to theses mentioned?
I had an ecobee do this this summer. It was a unit low on refrigerant and would trip out on low pressure turning on and off all day & it was 82 outside. The thermostat would read 114 and was as hot to the touch.
I've had a few housewise tstats do this. So far every "high tech" tstat we've carried had some issue with a decent percentage of them that goes back to using electronics that can't handle the basic stress of every day use. I hope they create something with decent software like the housewise that uses sturdier components. If anyone knows a good reliable wifi tstat let me know!
We've had similar issues with dozens of Cor/Housewise stats. So much so we no longer offer the product.
Older climatemaster thermostats will do that. Starts out as short cycling then if left alone will get bad enough they won't go into heat anymore.
I thought carrier fixed those issues, two years ago I had replace 3 of them, I had issues with WiFi and erratic displays, no heat pumps just straight cooling
I had a customer that had the same issue and they didn’t do any testing like you where. We replaced it once but then the new thermostat started doing it again several weeks later. We pulled it and put a Honeywell on it.
My guess is the O circuit had a shorted MOSFET bridge output. Could be a random quality control problem on the MOSFETs or their reverse bias diodes or could indicate parts that were not designed properly for the application. I might consider calling the manufacturer and or repeating the failure mode test on the new one.
I can see the problem from here. It's on the back side of the thermostat, all the way on the bottom. You are welcome………………………………………………. [Rant Mode: On] It's so sad, we used to make and sell great equipment and components here in this country, now it's all junk that you are lucky to get 10 years of service from.
There is a direct connection to the reversing valve?