Speak EV - Electric Car Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
3,223 Posts
Discussion Starter #1
This topic is not talking about cheap blow up tubs, but is more pointed towards the hard shell tubs or permanent fixture tubs.

Like anything in life some Hot Tubs are built with cheaper bits and some with better quality bits and from what i can see generally most parts inside a decent hot tub should last between 10-15 years.

Now I know the heating elements and pumps aren't always running in a tub and they cut in and out many times a day.
But the tub is very well insulated and has a super thick insulated cover that is always on it so my thinking is that by avoiding the peak it will pick up a little juice outside of the peak to get back to hot again but not much.
Its currently running at 38'c as well so not scorching but more than hot enough for our needs.

Now for a short while i have been testing using a Kasa smart plug on the hot tub feed to try and make it avoid the peak period which is between 2-3hrs a day generally.

Has anyone tried such a thing, have any hot tub manufacturers offered smart tubs that could possibly integrate with IFTTT to maybe work in such a way directly?
 

·
Registered
Joined
·
28 Posts
I can't answer your question but I'm interested in this too, I've also got a hot tub set (24/7) at 38 degrees, I recently moved from a lay-z-spa tub and spent a lot of time turning it up and down(even off) in an attempt to save on cost. Obviously a "proper" tub is designed to be ran 24/7 as it doesn't lend itself to being switched off, in theory the better insulation mitigates some of the expensive over the inflatable type.

I'm moving to Agile as soon as my smart meter goes in (3 weeks) so also want to avoid the 4-7 peak as much as possible. Mines on a 13amp plug to, so i could turn it off for 3 hours, this probably won't cause an issue, the only concern is that resets the filter cycle so immediately after 7pm I would have an hour of "filtering". I am looking at having a 32amp feed but in, so that would screw up the option of using a Tapo plug for example.
The requirement I guess would be a way to shutdown, just the heater for the peak period but leave the pumps running, this wouldn't really affect temp - 1/2 a degree max if the lids shut, but also wouldn't screw up the filter cycles when its re-energized and on the flip side use the cheap rate electric to give it a boost if its not on at that particular time.
 

·
Registered
Joined
·
972 Posts
I can't answer your question but I'm interested in this too, I've also got a hot tub set (24/7) at 38 degrees, I recently moved from a lay-z-spa tub and spent a lot of time turning it up and down(even off) in an attempt to save on cost. Obviously a "proper" tub is designed to be ran 24/7 as it doesn't lend itself to being switched off, in theory the better insulation mitigates some of the expensive over the inflatable type.

I'm moving to Agile as soon as my smart meter goes in (3 weeks) so also want to avoid the 4-7 peak as much as possible. Mines on a 13amp plug to, so i could turn it off for 3 hours, this probably won't cause an issue, the only concern is that resets the filter cycle so immediately after 7pm I would have an hour of "filtering". I am looking at having a 32amp feed but in, so that would screw up the option of using a Tapo plug for example.
The requirement I guess would be a way to shutdown, just the heater for the peak period but leave the pumps running, this wouldn't really affect temp - 1/2 a degree max if the lids shut, but also wouldn't screw up the filter cycles when its re-energized and on the flip side use the cheap rate electric to give it a boost if its not on at that particular time.
Could you just adjust the set temperature down for three hours then put it back to 38?
 

·
Registered
Joined
·
2,668 Posts
Personally I would look at adding a posstive offset of a few degrees to the set point when power is very cheap and locking out the heater when power is costly. Should be easy enough with a small computer driving a relay.
 

·
Registered
Joined
·
3,223 Posts
Discussion Starter #5
This is what I'm thinking.
Ideally I'd want a controller that could work with a ToD tariff to increase temp.magbe a degrees before the window and then get it back up after the peak. And then also see if there is a negative period and to allow a drop down before those negative periods and heat up then.
Don't get me wrong it's a new thing for the hot tub world but I wonder if a basic raspberry pie with some tweaking would do the job. I think it's going to be a fee years before we see a manufacturer doing it though but to think I may go back to the smart plug setup again to avoid the peak.
Also don't forget to keep the water level topped up so it's at or near max as that little air pocket at the top is wasted heat too.
 

·
EV Convert
iPace HSE / 2019 and eTron 55 / 2020
Joined
·
681 Posts
Hiya KP, are you on Octopus Agile? If so, one possible solution to this is to use a Sonoff 16A smart switch with IFTTT, Octopus have an ingredient for IFTTT that allows you to switch [something else] on/off based on tariff changes, or other factors such as [average cost over x periods]. Also works with Kasa but they won't take the current. Subs required now for IFTTT so it's not free unless you have minimal uses.
 

·
Registered
Joined
·
3,223 Posts
Discussion Starter #7
Hiya KP, are you on Octopus Agile? If so, one possible solution to this is to use a Sonoff 16A smart switch with IFTTT, Octopus have an ingredient for IFTTT that allows you to switch [something else] on/off based on tariff changes, or other factors such as [average cost over x periods]. Also works with Kasa but they won't take the current. Subs required now for IFTTT so it's not free unless you have minimal uses.
Hi A1GSS,

Yeah I've used the Kasa as a proof of concept but the bigger thing for me is how it could affect the hot tubs life span on parts as I'm fully turning it off and then back on again.
While it's not doing a filter run every time it turns back on I am partially worried about lifespan of certain things and wonder more if there is a better solution that can interface with a tub somehow even though they are pretty simple things.

I hadn't realised that IFTTT had become a cost service now but it was bound to happen. I kept thinking those price setting emails were for a pro or dev account I never ended up using 😥🤦‍♂️
 

·
Registered
Joined
·
28 Posts
Hiya KP, are you on Octopus Agile? If so, one possible solution to this is to use a Sonoff 16A smart switch with IFTTT, Octopus have an ingredient for IFTTT that allows you to switch [something else] on/off based on tariff changes, or other factors such as [average cost over x periods]. Also works with Kasa but they won't take the current. Subs required now for IFTTT so it's not free unless you have minimal uses.
i'm wondering if you could splice one of these onto the heater connection and set the schedule to be off during peak time, i guess the issue would be that the sonoff would be powered on and off multiple times a day as the tub stat did its thing outside of the peak hours

at least for me that would solve the problem of the re-energizing and the subsequent filtering cycle, assuming the tub doesn't throw up an error if it can't detect the heater...
 

·
Registered
Joined
·
3,223 Posts
Discussion Starter #9
I have come up with an alternative method due to what I have access too...

Instead of the hot tub plugging straight into a socket, I'll have inline a UPS similar to this
And then have that plumber in via the Kasa smart plug so while the tub is always powered, the ups isn't so can avoid the peaks...

It's a bit overkill but the tub is right next to a shed so I have the space, it's carpeted and doesn't get that cold in the depths of winter so will stay within the temperature tolerance to a certain extent.
I can also expand it with another shelf so doubling run time too 😁
 

·
Registered
Joined
·
3,223 Posts
Discussion Starter #11
that's a pretty neat solution, assuming you don't have to pay the £1800 for the UPS :D
Oh god no!
Also have some big old 12v car batteries i can use to extend it even further, fingers crossed it goes well, its going to be heavy and i need to cable in the UPS as its on a 32amp commando currently so that needs doing right :)
 
1 - 11 of 11 Posts
Top