Touch - US Version Air Conditioning issue and general first thoughts


#1

After all the trouble with customs getting my unit here (eased by the wonderful support at Hestia), I have had my Hestia installed and running for a few months now.

Initially the screen turning black until a reboot was annoying, but it wasn’t long before you had a fix up. Everything was great.

I live in Texas. I already need my air conditioning. I noticed something odd a few weeks back for a day, but couldn’t put my finger on it. Cold front hit, back to heater, problem forgotten. Today I sat down and payed attention as the temperatures in my room climbed and I kicked on the A/C. Again, something not quote right:

  1. The A/C kicks on really hard. I don’t know if it’s the type of relay, or the voltage supplied to it, or maybe just my imagination telling me it’s harder, because it’s kicking on so often. Which leads to problem 2

  2. The temperature is cooling until it reads the temperature below the set MAX temperature, and then kicking back off. So it only cools for one degree, and then it only heats up one degree before it comes back on again. I tried swapping the min max values, but the max moves with the min. I assume that is just a logic issue, where it’s cooling to the max value as if it were a heater, and just needs to cool to the min value. Which leads to problem 3.

  3. I can’t ssh into my hestia after a while. I don’t believe it to be my router so I am asking more than telling. It does not show up on FING. I can, however, ping it and access the openhab interface and still use the unit. IS this something other users are experiencing?

Other than that, the unit is great. It’s a little slow, and I would love to run it from my synology openhab instance to utilize it’s processor, ram, and storage space (using your pi as more of a sensor itself). I may do this with using mqtt.

Any help you can offer would be greatly appreciated!

Best Regards,
Dan


#2

The relay is simply on or off. Is your HVAC system a 2-stage system that starts slowly if only a little is needed but if more heating/cooling is needed it goes to stage-2 where full power is used?

That does not make sense as Fing uses ping too. If Fing does not find it, you shouldn’t too. 2 possible scenarios are here:

  1. Have you assigned a static IP to Pi? If not, the IP has changed and you ping another device in the network. How to do you access the Openhab interface? Using the IP or via myopenhab.org (cloud connection if you enabled it)?
  2. You use Fing on a separate device than you try pinging and the 2 devices are connected to separate networks. One network (the one pinging) is shared with the HestiaPi and the other is isolated (Fing).

Having said that I must admit that since we migrated to Raspbian Stretch we do see some weird issues reported from time to time where troubleshooting is “impossible”. Moving back to Jessie (images 9.x) will be reconsidered if pilot users confirm stability is restored for a 1-2 month period. If you decide to use a 9.x image you will have to enter your WiFi credentials in a different way explained in the image page. We know moving backwards to a previous version may not be a desirable decision but if Pi Zero W can support that much weight, then we need to consider that option too.


#3

Does the thermostat hysteresis and short cycling prevention ?

If so, the heating system should not kick in for a good while after the cooling circuit has run. At least 15 minute.

Also whenever the target temperature is reached, neither heating nor cooling should start again until a delay has elapsed (could be 1 to 5 minutes for heating, 5 to 10 minutes when cooling) and the sensor temperature should have changed a certain minimum amount (could be two degrees C not just one C or one F).

Also, the fan should continue running for a certain time after heating or cooling has completed.

The system should also detect when target temperature has overshot and compensate for it over time (taking into consideration outside temperature and maybe also outside wind speed and maybe maybe wind direction )


#4

I do not believe it to be, however, I think what I am noticing is what Shodanx talks about below. I’m used to the fan kicking on first and then the compressor. I believe both coming on at the same time, is a noticeable draw over my conventional thermostat, and why I think it is kicking on harder. Also the sound of the compressor kicking on is lessened by the noise of air blowing through the house. Now I hear it all at the same time. This was not actually my primary concern, but something that possibly needs to be looked in to.

I felt the same way about the ping Fing scenario, I am not having issues with other devices. All can be accessed over the internet via ddns, but several devices are hidden to my intranet. I will get to the root of this, but believe it to be network issues on my end, and not the pi bogging down (because I can still get to it remotely).

This was actually my main concern. Because everything was already coming on abruptly, coming on so often was really an issue. I have found the problem in the default rules, and have updated my unit with success. Attached is an image of the line I updated from TempMaxSetpoint to TempMinSetpoint. Small error, no big deal.


#5

This is a feature to be added in the next release for both HVAC and International models. We will be adding a threshold of certain degrees that will be taken into account when comparing current temperature with setpoints. Your photo is the right spot where you can simply hard code a +/- x’F. The way we will do it is with a variable linked to a mode option with Eco and Comfort values. ECO will allow higher fluctuation (so that x mentioned before will be something like 3 degrees) while Comfort will be narrower. Of course the numbers need to be tested first, so feel free to suggest your own here.


#6

I saw the threshold values in there.

So you’re saying the set temperature was intentionally coded for cooking so it wasn’t supposed to go below the max value? I am instead supposed to set a threshold around the max value and only use it for temperature? (Disregarding min?)

I had not been using the heater that way. I’ve been using the distance between the max and min as my threshold.


#7

Apologies. You are right. The EU model only is lacking the feature I was describing.
We may need to add 2 delays for the HVAC model for its fan in the heating and the cooling mode. Would that solve your problem?


#8

This is a step in the right direction. My wife tolerates my experiments, however, having to wait on the screen to go to a settings page and set two values does not bode well for the longevity of my hestia. It needs to be a single value on the front page, with a plus or minus that has the threshold you suggest above applied. This makes it much more conventional and helps to hide some of the lag issues the unit experiences due to the screen.

I would love to test this for you if you want to whip something up and send me an image.

Best Regards,
Dan


#9

Maybe the crowdfunding campaign will produce a simpler UI as we can understand what you are saying.
An attempt to unify the US and the EU requirements in a smart transparent way is on the way.
At least a faster UI is our top priority.


#10

The ui is simple enough to change. I need the code for floating above and below the set value by a given value. Set to 72, it waits to 74 to kick on, cools to 71. Instead of seeing two values.


#11

Well done Dan !