Yeah I don’t think I can turn it upside down. I agree that the cover is probably not my problem. I have a bunch of other thermal images I took and some portions of the exterior of the hot tub are reading 60 degrees. The outside temp is 17. That tells me I have a major heat loss problem if the outside of the frame is warm to the touch at 60 degrees.

Ideally the manufacturer and place I bought the hot tub would care about this, but my sense is I am on my own. The question is, what’s my best way to re-insulate this thing?
How did you get the thermal image? Would love to see what mine looks like. Mine feels cold to the touch on the outside on the top and sides.
 
Just checked my electric meter, and I appear to be burning through 70kw per day (Total household) still. That is after putting in more insulation and changing the temp from 103 to 99 between uses. So, it appears as though doing those things has not reduced my electricity usage. I was expecting to get a bit of a "lift" from those 2 things.
 
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Just checked my electric meter, and I appear to be burning through 70kw per day (Total household) still. That is after putting in more insulation and changing the temp from 103 to 99 between uses. So, it appears as though doing those things has not reduced my electricity usage. I was expecting to get a bit of a "lift" from those 2 things.
My next experiment will start in about 1 hour. I'm going to turn the tub temp to 80 degrees for twenty four hours. Theoretically the heater should not run during this time (Unless the tub drops from 99-80 in twenty four hours). Based on my math, the heater runs on average 6 hours per day adding up to 24kw usage (6 hours x 4kw heater). So, my twenty four hour meter reading could be close to 20-24 kw less over that twenty four hour period.

Also, next week my electrician is going to come over and run some tests to see if something is drawing more power than it should be.
 
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How did you figure out how long the heater is running for?

From what I understand, the spa pump motor periodically turns on to determine if the water is cold enough to run the heater. However, it does not mean the heater actually runs for the entire cycle or even at all. Does the controller actually keep track of the heater run time or are you assuming it is running when the pump runs?

Our power company has upgraded our power meter with an IoT wireless system such that I can now go online and see the power usage of my home in 15 minute increments. Something to check on with your power company.
 
How did you figure out how long the heater is running for?

From what I understand, the spa pump motor periodically turns on to determine if the water is cold enough to run the heater. However, it does not mean the heater actually runs for the entire cycle or even at all. Does the controller actually keep track of the heater run time or are you assuming it is running when the pump runs?

Our power company has upgraded our power meter with an IoT wireless system such that I can now go online and see the power usage of my home in 15 minute increments. Something to check on with your power company.
Good question. These are estimates on my part, but so far pretty accurate. Given my power consumption increased by approximately 970kw during my first month of ownership, I did some calculations. I know my spa parts and amperage, which I then converted to Kw's. The default for my single 2 speed pump is for it to run twice per day for 2 hours on a filter cycle. So that will run at least 4 hours per day. But, when the tub calls for heat, and the heater kicks in, it also runs the pump on low speed. Then, I use the tub for 30 minutes each day and run one 20 min high speed jet cycle. To generate the type of increased Kw consumption I experienced, it has to look something like the below table.
Screenshot 2025-01-24 at 1.46.16 PM.png
 
A 4000 watt heater run for 6 hours will consume 24 kWh's. Since nothing else in the tub will be drawing 4000 watts, 6 hours is a reasonable estimate.
Agreed. Already since I turned the temp on the hot tub down to 80 degrees (From 103), the hot tub has lost 4 degrees. That is approximately 1 degree per hour so far. And that math lines up perfectly with the heater running 6 hours per day (With assumption that a 4kw heater can increase the tub temp by four degrees every hour). If my tub is losing 1 degree every hour, then in 24 hours it is losing 24 degrees. And 6 hours of a 4kw heater running daily heats it up approximately 24 degrees.

Tomorrow at 9:45am EST I'll see what the tub temp is. If I'm right, the heater will be running and the temp will show 80 degrees. Which, really only reinforces what I know......extreme heat loss. But, even people with inflatable hot tubs seems to have better performance than this. So, something is very friggin wrong here.
 
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You have confirmed that the pump is running on low speed while the heater is on? Some controllers will automatically switch to high speed while the heater is running.
 
You have confirmed that the pump is running on low speed while the heater is on? Some controllers will automatically switch to high speed while the heater is running.
Yes, visually I have. What I mean by that is I suppose I can't know for sure without connecting an amp meter. But when the heater kicks on, the tub looks and sounds the same as when it's in a filter cycle.
 
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Without any insulation on the shell, the water is basically in contact with the cold air making its way in and around the tub interior. The shell itself is very thin, even in a rotomolded tub so it has almost no practical R-value. The foam insulation that is supposed to be sprayed on to it is what gives it the heat retention properties.

You’ve certainly done enough analysis to show how poorly it’s performing. The manufacturer ought to make this right and just send you a new tub with the correct insulation installed. Seems to pretty obvious that they screwed up and sent you a tub with no insulation. Or maybe this is how they insulate their tubs and they’re just not designed to be used in such a cold environment. Either way, the manufacturer needs to step up.
 
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Without any insulation on the shell, the water is basically in contact with the cold air making its way in and around the tub interior. The shell itself is very thin, even in a rotomolded tub so it has almost no practical R-value. The foam insulation that is supposed to be sprayed on to it is what gives it the heat retention properties.

You’ve certainly done enough analysis to show how poorly it’s performing. The manufacturer ought to make this right and just send you a new tub with the correct insulation installed. Seems to pretty obvious that they screwed up and sent you a tub with no insulation. Or maybe this is how they insulate their tubs and they’re just not designed to be used in such a cold environment. Either way, the manufacturer needs to step up.
I spent a lot of time researching and working with the dealer to choose this hot tub. Full Foam is standard on all these models. Plus I paid and additional $300 for their "Extreme" foam additional service for cold winters in New England. So, they definitely screwed it up during the manufacture process. I also got an extended 5 year warranty beyond the standard. I agree they should send out a new one that is properly built. But, something tells me I'm going to get scr#wed and get zilch from them. I'm a pessimist. So, I'm trying to figure out how to handle improving the situation if they do the wrong thing and hang me out to dry.

Screenshot 2025-01-24 at 2.33.47 PM.png
 
Are you able to compare your foam with the one on the dealers showroom? I'm guessing if theirs is significantly better it can only.help your cause.
 
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This picture you posted shows quite a bit of foam. Do you have other pics that show more empty area?

View attachment 625626
Yeah good point. That foam is covering the hoses and components. That gap to the right is empty....nothing there except like a 85 degree heat coming off the shell of the tub due to the water temp. It's like that in all 4 corners and on the top section of the shell too. I can find no evidence that there is spray foam on the shell whatsoever, just the components.

If I had to guess, the team or person responsible for foaming this particular tub just opened the panels on each side and sprayed only what was in front of them. They did not spray to the right, to the left, down or up. At the top of this photo, you can see a black cable and exposed shell. That would have been easy to spray with the foam gun. And there is like 6 inches of tub shell above that is unsprayed too, all the way around the entire tub. So, that exposed spot at the top of this photo is kicking off like 80 degree heat into the cabinet.
 
Are you able to compare your foam with the one one the dealers showroom? I'm guessing if theirs is significantly better it can only.help your cause.
Not yet. I might drive there this weekend to see how theirs looks. However, it's not uncommon for showrooms to have bare bones models with no insulation. So, it could work against me too I reckon.
 
Isn't where the red arrow is pointed the inner shell of the tub? That is all that really needs to be insulated, plus maybe the pipes. From this picture it looks like at least 2" on most of the inner shell of the tub which is why I used that number in the analysis I did previously. However, the arrow is where some was missed.

1737749071210.png
 
Isn't where the red arrow is pointed the inner shell of the tub? That is all that really needs to be insulated, plus maybe the pipes. From this picture it looks like at least 2" on most of the inner shell of the tub which is why I used that number in the analysis I did previously. However, the arrow is where some was missed.

View attachment 625630
Maybe this picture will help explain. The red boxes are where there is no insulation at all. The blue box is where there is insulation. Now picture that on all 4 sides. That's a lot of uncovered tub shell.

I added a thermal photo for some reference. I drew a blue line around a spot I must have insulated well yesterday. My previous thermal image of that area showed it as a hot spot.
Screenshot 2025-01-24 at 3.08.21 PM.png


20250124T132709.jpg
 
Here is a pretty good example of how tubs are insulated. I think you might have something close to the middle one or the one on the left. The one on the right may have the best performance but a PITA to repair. In reality, the middle version should not be that much worse than one on the right if covered sufficiently.


1737749913710.png
 
Here is a pretty good example of how tubs are insulated. I think you might have something close to the middle one or the one on the left. The one on the right may have the best performance but a PITA to repair. In reality, the middle version should not be that much worse than one on the right if covered sufficiently.


View attachment 625638
Agreed. There is just so much heat filling up pockets in the cabinet due to zero insulation on the shell. If I had easy access to the shell I might be able to insulate it better on my own. But because there is so much foam sprayed like in the photo you saw, there is only a 1-2" gap for me to stick my hand in. I stuffed insulation in there, but I just can't pack it in tightly enough to make much of a difference.
 

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