Tempurature Profile Oddities

We installed a cold climate heat pump in Oct & I am trying to figure out why the temperature profiles for heating mode are flat. It’s calculating that the heat gain is only 0.2c / hour… and based on that times to heat are usually flagged to be 4+ hrs. In reality though, the system heats much faster than that. Cycles when it’s below freezing are between 45m - 2hrs depending on the temperature outdoors.

Looking at the graph, it looks like it’s registering measurements in the negatives that I don’t fully understand. I have a heat differential of 0.3c & when the system starts it’s heating cycle, the temps normally drop to about 0.8c. Here’s an example from last night where the house dropped to 18.7c at 1:40am and took to 3am to return to the set 19.5c. If the 0.2c/hr was the actual time to heat, it would have taken ~3+ hrs full the full cycle (couldn’t add the 2nd capture here being a new member :slight_smile: )

I’m wondering if the temperature profile data is using the differential to measure the time to heat or if it uses the actual measured temp and calculates slopes that way?

I increased your trust level so you can add more photos now. :slight_smile:

The profiles sample your actual data. So if it’s 1°C outside and your heat runs for 1 hour, increasing the indoor temperature by 0.8°C, that’s the data that will be captured. Samples that are outliers are then removed, then everything is averaged together to produce the profile.

If you send me your thermostat serial number I can export the actual sample data for you to skim through. It might shed some light on what’s going on.

Thanks! I think I have some funny data throwing the charts off earlier in the year, so I changed the period to just use the last 7 weeks and it reads a bit more normal. The balance point is all thrown off, but that was expected because it’s not been cold outside in that period of time

Hey @ziebelje DM’d you my serial#. Let me know if that is sufficient to spy on my data. I still think the slope is affected negatively by the data being captured, since my temperatures drop meaningfully in the first 15-20mins of my heatpump starting up. The profile is registering obvious negative values in the app.