Accuracy with multi-stage devices?


I have two elertric heat devices that sense has picked up, but only the partial load.

One is an electric heater. It functions at 700W, 1000W, and 1500W. Interestingly enough, Sense will only pick up the last 500W, so when it’s on high.

I only have a hot tub that uses 5,500W. Sense picks up ~2,900W.

Has anyone else noticed this? Will it eventually learn the rest?

I’m thinking this might also be likely to occur with multi-stage heat pumps, unitary A/C, ductless A/C, or multi-stage furnaces. Anyone?


I’m guessing this is at least partly related to my 240v post a week or so ago. I think your hot tub second leg will get found, I’m skeptical about the multi-level heater.

Sense is certainly evolving, though, so maybe there’ll be a push to try to model-fit some of the more complicated appliances (or subtle ones - like my relatively new and efficient fridge), after they finish modeling EV chargers.


I have the same issue with my heat pump. It has 5 stages of heat:

  1. 2 ton compressor
  2. 4 ton compressor
  3. 4 ton compressor + 5000W Aux 1
  4. 4 ton compressor + 5000W Aux 2 + 5000W Aux 2
  5. 4 ton compressor + 5000W Aux 2 + 5000W Aux 2 + 5000W Aux 3

Unit is a Trane XL20i. The thermostat tells which stages are on and Sense it very confused except about stage 1.


Huh. Interesting. Does the compressor use 120V or 220V? Sent with Mailtrack


The system uses a total of 3 220V breakers. The indoor unit is feed via a 60A and a 30A breaker. The outdoor unit is feed via a 40A breaker and contains 2 compressors inside a single housing. So it is a 2 stage compressor, but instead of using a single compressor running at either 50% or 100% capacity like most dual stage heat pumps, it actually has 2 distinct compressors. The advantage is higher efficiency. A single compressor running in stage 1 still consumes about 70-80% of the power it would running at full capacity (stage 2).


I noticed today that Sense has picked up one leg of my 220 on my hot tub as “unnamed heat 2” and the other leg is still in “unknown”. It also picked up my hot tub pump as “unnamed motor 1”. It has picked up my Geothermal furnace but I think it was confused very early this morning when we regained power when my Geo kicked into stage 2 heating and then to auxiliary heat. It ended up in “unknown”.


Interesting. These are “unknown”, so you can connect name them, correct?

Also, what monitoring do you use for your GSHP performance? Do you use:

Chris Sent with Mailtrack


If they are in the “unknown” I cannot name them.
At this time, I do not have monitoring on my GSHP. It is a Waterfurnace and I’m in the process of having that installed sometime this year. It is called Symphony.


Oh, sorry for the confusion. How are you monitoring it if it isn’t
installed yet?! Sent with Mailtrack


My thermostat has limited abilities. It will tell me if its in stage 1, stage 2 or auxiliary heat. It will not yet tell me of the power consumption. I only know that through Sense by watching my thermostat and Sense at the same time.

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