Understanding my temp profile

Can someone please explain to me if this is bad or good ?

1964 old (fully renovated bungalow in Montreal) 2 stories, new heat pump / electric furnace (2T).

I may have a problem with the insulation ?

The heat/cool/resist lines all look fine. The data is fairly consistent and the slopes are correct. Whether or not it’s “good” depends on what you’re comparing. Some of the data on the Metrics page is really better for that type of analysis.

The aux heat line is the only one that’s a bit off, but that’s somewhat expected. Either gas or heat strips will tend to have a horizontal line as they are not affected by outdoor temperature like a heat pump is. At those very cold temperatures you may see it boosted (and thus driving the negative slope) if you ever run fireplaces, space heaters, etc as the heat generated from those will happen to get factored in.

Thanks for the reply, actually I am trying to understand 2 things:
1- Do i have a good insulated house ?
2- My new heat pump (installed December 2021) is undersized and I may need to replace it by a bigger one ?

This is the metrics page, I am still struggling to understand some of the numbers like Runtime per degree day and Resist

Here’s a good place to start.

Based on your data I would say your home is pretty average. As always, though, it depends what you’re looking at. Beestat is geared towards showing you data and letting you decide if it’s good or bad based on your own preferences and life situation.

Your heat pump does not look undersized to me. You can sort of gauge this with the balance point. Yours is -13.9°C, which is lower (better) than most others in your comparison group. This is the outdoor temperature at which your heat pump can no longer heat your home and an auxiliary heat source is needed. Another thing you can look at is overall runtime on your history charts. On the coldest day of the year you should expect it to run pretty much constantly, with maybe a little help from the aux heat.

Insulation is a little trickier since there are a lot of factors to consider. One thing you could look at is runtime per degree day. This is basically a measure of how long your system runs but normalized against the outdoor temperature. Low numbers here could indicate an efficient heat source, good shade from trees in the summer, or solid insulation that helps keep runtime down. Only you can really know which it is, but your numbers here look average or better.

Hope that helps! Let me know if you have any other questions. :slight_smile:

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My heat pump energy consumption is driving me crazy :upside_down_face:!

Aux turned ON at 6am - from the Hydro site, energy consumption 4.1Kwh

at 4pm , 6pm, 7pm - same scenario, but consumption is >7Kwh for every hour

I really don’t understand why !!

And if I look at the 6am consumption, I’d say it’s more efficient to engage the Aux for few mins every hour, but when looking at the afternoon consumption, I’d rather stay with heat pump ON all the time (around 3.5 Kwh to 4.4Kwh)

Any help to understand would be appreciated!

Interesting. So how relevant is the Resist number if you don’t have a heat pump. We heat with natural gas and the resist is 17.5. This is higher than 82% of the homes around me. Does this mean our home is not well insulated? Is there anyway for me to calculate what it would have been January 2022 or 2021.

Resist is still relevant since it’s related to your home when your system is not running. It’s difficult to say what value is objectively “good” here though. I believe you would want this value to be as close to the average outdoor temperature for the entire year as possible. That should correlate to less overall runtime.

Beestat doesn’t currently have a native way to show old values here. Re-calculating based on historical data isn’t feasible since that old runtime data is destroyed after a year. However, I have been saving the profile calculations for about 8 months. If you want me to send you that data just shoot me an email with your thermostat serial number.


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