Discussion
Superleg48 said:
Heres Johnny said:
The laws of physics don’t really support this argument, it might depend how often you’re heating it up, but heat loss is proportional to the temperature difference between the water and ambient, the hotter the water the greater the loss. We found turning ours down to a standby temp reduced the electricity needed to maintain it and would only take an hour or so to get up to temp when we wanted to use it,
We also switched to bromine as chlorine caused some mild skin irritation, it seems to be just preference really.
The laws of physics as you put it absolutely do support the argument that if you let a tub go cold and reheat to say 38 degrees On a cyclical basis each time you want to use it, you will use more energy than setting the temp at 38 degrees and leaving it there. If you are found a little time between uses, then yes, reducing the temp to say 30 degrees will reduce energy consumption slightly too, until you want it to go back to 38 degrees and voila, more energy required for that process. The tub is extremely well insulated (if it is a decent one) so maintaining the temp steady is not so affected by ambient temps as you might think. We also switched to bromine as chlorine caused some mild skin irritation, it seems to be just preference really.
Questions been asked many times
https://physics.stackexchange.com/questions/378502...
We’ve got a jacuzzi one. With hindsight I wouldn’t be as keen as I was at the time to have one again, but my wife would disagree. Since I have a couple of weekend cars that hardly get driven and take up space it’s more than a fair exchange.
Also, given the last 12 months of lockdowns, restrictions etc it’s been a great source of fun for the children. Had friends over at the weekend and the kids loved splashing around and spraying each other with water pistols. Does mean we’ve been varying the temperature between 34 and 38 degrees, but not noticed much of a change in running costs.
Also, given the last 12 months of lockdowns, restrictions etc it’s been a great source of fun for the children. Had friends over at the weekend and the kids loved splashing around and spraying each other with water pistols. Does mean we’ve been varying the temperature between 34 and 38 degrees, but not noticed much of a change in running costs.
PushedDover said:
I can only imagine the chuff of getting one of those up to temp for when you want to use it,
Then realising its gone thermonuclear and hot enough to boil potato's in.
They are a hot bath, versus a spa / hot tup with jets , non?
Yep sod that, “Fancy a tub in a bit?” 4 hours later.......Then realising its gone thermonuclear and hot enough to boil potato's in.
They are a hot bath, versus a spa / hot tup with jets , non?
We turned ours off over the winter, it was costing close to £80 a month to run while we weren't using it. I never used the eco mode so no idea what difference that would have made. It's going back on in a couple of weeks so when we're not using it i'll set it to eco. Heat loss in the winter is a lot more prevalent then warmer months. Since we got our smart meters, i noticed if i heated it from cold it would cost around £12 to get to 38 degrees.
Bromine and Chlorine basically do the same thing but Bromine is better for your skin so it's personal choice.
Bromine and Chlorine basically do the same thing but Bromine is better for your skin so it's personal choice.
Julietbravo said:
Has anyone got one of the wood fired ones? The ones that look like a barrel with the flue running up the side.
Look on page 2 about halfway down...Since I posted earlier in here, we eventually bought one of the Lay-Z-Spa inflatable ones to run for a year and see how we get on with it before committing to the expense of buying, installing and running a "proper" one. So far very happy with the Lay-Z-Spa, the massage jets are more powerful than I expected given they're air jets in an inflatable tub. Easy enough to maintain if you check the water chemistry daily and check and rinse the filter every three or so days. Not a bad way to dip a toe in (pun intended) if anyone else is thinking about this but wary of the cost of a full-fat one.
8bit said:
Look on page 2 about halfway down...
Since I posted earlier in here, we eventually bought one of the Lay-Z-Spa inflatable ones to run for a year and see how we get on with it before committing to the expense of buying, installing and running a "proper" one. So far very happy with the Lay-Z-Spa, the massage jets are more powerful than I expected given they're air jets in an inflatable tub. Easy enough to maintain if you check the water chemistry daily and check and rinse the filter every three or so days. Not a bad way to dip a toe in (pun intended) if anyone else is thinking about this but wary of the cost of a full-fat one.
The layzspa are a great way to find out if you would actually use a proper version. Since I posted earlier in here, we eventually bought one of the Lay-Z-Spa inflatable ones to run for a year and see how we get on with it before committing to the expense of buying, installing and running a "proper" one. So far very happy with the Lay-Z-Spa, the massage jets are more powerful than I expected given they're air jets in an inflatable tub. Easy enough to maintain if you check the water chemistry daily and check and rinse the filter every three or so days. Not a bad way to dip a toe in (pun intended) if anyone else is thinking about this but wary of the cost of a full-fat one.
I use mine 15-20 nights a month when I'm home. It uses a around £60 a month in electric for heating now that I have properly insulated it (custom build) . Barely half a tank of diesel for the car. Looking after it with the test strips and chlorine tablets is very simple.
Uggers said:
The layzspa are a great way to find out if you would actually use a proper version.
I use mine 15-20 nights a month when I'm home. It uses a around £60 a month in electric for heating now that I have properly insulated it (custom build) . Barely half a tank of diesel for the car. Looking after it with the test strips and chlorine tablets is very simple.
Yeah, it's no real hassle at all once you get used to it. Interested in your custom build insulation, would you mind sharing some details and perhaps a photo or two?I use mine 15-20 nights a month when I'm home. It uses a around £60 a month in electric for heating now that I have properly insulated it (custom build) . Barely half a tank of diesel for the car. Looking after it with the test strips and chlorine tablets is very simple.
Superleg48 said:
Heres Johnny said:
The laws of physics don’t really support this argument, it might depend how often you’re heating it up, but heat loss is proportional to the temperature difference between the water and ambient, the hotter the water the greater the loss. We found turning ours down to a standby temp reduced the electricity needed to maintain it and would only take an hour or so to get up to temp when we wanted to use it,
We also switched to bromine as chlorine caused some mild skin irritation, it seems to be just preference really.
The laws of physics as you put it absolutely do support the argument that if you let a tub go cold and reheat to say 38 degrees On a cyclical basis each time you want to use it, you will use more energy than setting the temp at 38 degrees and leaving it there. If you are found a little time between uses, then yes, reducing the temp to say 30 degrees will reduce energy consumption slightly too, until you want it to go back to 38 degrees and voila, more energy required for that process. The tub is extremely well insulated (if it is a decent one) so maintaining the temp steady is not so affected by ambient temps as you might think. We also switched to bromine as chlorine caused some mild skin irritation, it seems to be just preference really.
The energy required to raise 1kg of water by 1 degree is fixed. Electric heating is 100% efficient so there are no losses due to the heating processes.
That's just physics.
Nickyboy said:
We turned ours off over the winter, it was costing close to £80 a month to run while we weren't using it. I never used the eco mode so no idea what difference that would have made. It's going back on in a couple of weeks so when we're not using it i'll set it to eco. Heat loss in the winter is a lot more prevalent then warmer months. Since we got our smart meters, i noticed if i heated it from cold it would cost around £12 to get to 38 degrees.
Bromine and Chlorine basically do the same thing but Bromine is better for your skin so it's personal choice.
Interesting approach to using the tub. The colder it is outside, the more likely we are to use the tub.....though not if it's blowing a gale or lashing down (it's outside with no coverings/gazebo etc). It's best if the snow is falling !Bromine and Chlorine basically do the same thing but Bromine is better for your skin so it's personal choice.
We definitely use the tub more in the winter than the summer. Agree on Chlorine / Bromine.
Steve Campbell said:
Interesting approach to using the tub. The colder it is outside, the more likely we are to use the tub.....though not if it's blowing a gale or lashing down (it's outside with no coverings/gazebo etc). It's best if the snow is falling
Exactly the same here. I can only think of a handful of times over the years when we've used ours in daylight. Even then it's likely to have been a rush to get out and into it because it had started battering down with rain or snow. Outdoor tub in the lashing rain is great.98elise said:
No it doesn't. You are heating to make up for the losses. Losses are proportional to the temperature differential. While the water is cooler the losses are smaller so you use less energy. If you let the water drop to ambient you will use no energy.
The energy required to raise 1kg of water by 1 degree is fixed. Electric heating is 100% efficient so there are no losses due to the heating processes.
That's just physics.
Losses are indeed proportional to the temperature differential between water and ambient air, however those proportions are impacted by the level of thermal insulation that the hot tub provides. A well insulated hot tub will lose less heat where the differential is greater than a less well insulated tub and therefore use less electricity to maintain steady. My comment was based on a well insulated tub. The energy required to raise 1kg of water by 1 degree is fixed. Electric heating is 100% efficient so there are no losses due to the heating processes.
That's just physics.
I don’t understand the relevance of your last sentence to the point. Please don’t try to clarify, though. Do not wish to derail the thread with this debate.
Superleg48 said:
98elise said:
No it doesn't. You are heating to make up for the losses. Losses are proportional to the temperature differential. While the water is cooler the losses are smaller so you use less energy. If you let the water drop to ambient you will use no energy.
The energy required to raise 1kg of water by 1 degree is fixed. Electric heating is 100% efficient so there are no losses due to the heating processes.
That's just physics.
Losses are indeed proportional to the temperature differential between water and ambient air, however those proportions are impacted by the level of thermal insulation that the hot tub provides. A well insulated hot tub will lose less heat where the differential is greater than a less well insulated tub and therefore use less electricity to maintain steady. My comment was based on a well insulated tub. The energy required to raise 1kg of water by 1 degree is fixed. Electric heating is 100% efficient so there are no losses due to the heating processes.
That's just physics.
I don’t understand the relevance of your last sentence to the point. Please don’t try to clarify, though. Do not wish to derail the thread with this debate.
I'm no physicist so maybe I'm missing a key difference here, but we have a wet underfloor heating system in our dining kitchen extension. To start with I had the programmable thermostat set such that the air temp overnight was lower than through the day, thinking we'd save some energy by not heating it as warm when we're asleep anyway. I ran it like that for a couple of weeks, then set to a constant temp for a couple of weeks. We found it used less energy keeping a steady temperature 24x7 compared to dropping the temperature overnight.
I was assuming that the same would apply with our Lay-z-spa, it does have some sort of energy saving setting but I never bothered yet to investigate that for the above reason.
I was assuming that the same would apply with our Lay-z-spa, it does have some sort of energy saving setting but I never bothered yet to investigate that for the above reason.
Steve Campbell said:
Interesting approach to using the tub. The colder it is outside, the more likely we are to use the tub.....though not if it's blowing a gale or lashing down (it's outside with no coverings/gazebo etc). It's best if the snow is falling !
We definitely use the tub more in the winter than the summer. Agree on Chlorine / Bromine.
TBH i was in the same mindset, i couldn't wait until it snowed but we had turned it off by then. I didn't mind going outside so much but the g/f wouldn't go outside when it got cold. The now didn't last long enough to turn it again We definitely use the tub more in the winter than the summer. Agree on Chlorine / Bromine.
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