How to keep heat in a hot-tub? - Tilted Forum Project Discussion Community

Stompy · 11-28-2004, 04:44 PM

My girlfriend's parents gave us their hot tub, and during the winter months, the bastard runs our electric bill up like you wouldn't believe.. two consecutive months last year had it up towards $150 (ours is normally $80, max).

I know the top sucks.. it's really old, one of those brown "fold-in-half" type lids. It actually broke on us recently, so there are two half-lids resting on top of the tub.

I heard about these little thermal covers that lay on top of the water itself that keep most of the heat in, and when used with a good lid, insures that you aren't wasting energy.

I can find several on google, but I'm not sure how good they are or if they actually work wonders. Does anyone have experience with these, or does anyone have any specific models/brands of covers (thermal or otherwise) they use that keep the heat in?

wondash · 12-01-2004, 06:03 AM

I'd suggest three things;

1) Buy a new spa cover. Covers only last about 5 years. After that they tend to sag (or worse, rip in half). Since we're also in the market for a new cover, I've checked out some web sites. Most charge between $250 and $350 for a decent cover (up to 8'x8'). For a small extra charge, you can increase the foam density which will increase in the R factor. Check out Factory Direct Spa Covers or Poolandspa.com.

2) Buy a Thermal Cover. It won't work wonders, but every bit of heat retention helps. They're cheap, and some online sites may throw it in for free when you purchase a hard cover. It doesn't really matter where you buy it from, they're all the same. Basically it's just a heavy duty version of bubble-wrap. Keep the bubble side up. They only last a couple of years, then the plastic tends to break down.

3) Don't keep the spa at full temp (100-102) unless you plan on using it two or more times a week. This will save you the most $$ on your electric bill. Lower it to around 80 degrees (or put it in econo mode). Most spa's can increase the temp from 80 to 100 in about three or four hours (depending on how cold the outdoor temp is). This means you need to set it to full temp at dinner time, so it's ready to use later that evening.

Hope this helps. It worked for us.

Stompy · 12-04-2004, 09:12 AM

Sweet, thanks a ton!

I'm gonna be going out today to check out some covers at a spa shop around here.

That, in conjunction with the thermal cover, should definitely do the trick!

noblejr · 12-04-2004, 09:11 PM

If you want a big project, you could build a gazebo with removable insulated walls that you use in the winter, and put them away in the summer to have a nice open gazebo. It's a bit much, but will probably pay for itself in a few winters of heat savings.

Hard8s · 12-05-2004, 05:25 PM

Also check that the insulation on the tub itself has not disappeared. If so make sure to put insulation back up under the tub. Blocks, spray foam, anything to help keep the water temp up. Also when you put one of those bubble covers on the water, try and make sure you don't get any water on the top of it. Any water on top is like having a hole in the cover.

wondash · 12-07-2004, 05:55 AM

noblejr and Hard8s both have good suggestions!

c172g · 12-16-2004, 01:02 PM

We had a jacuzzi tub at our last house. There isn't anything you can do but budget a dollar a day for running the thing. We tried everything. In the summer, it obviously doesn't take much to keep it warm (plus in 80 degree weather, 102 is probably just fine). In the middle of winter, our power bill was the same as yours, even with a new thermal cover, about $150 or so per month. We kept ours at 104 & would turn it to 106 at about 8 every night, by the time the kids were in bed at 10 it would be 106. When we got out we'd turn it back down a few degrees. We live in northern Michigan & that's just the expense of having the toy.

kazoo · 12-16-2004, 08:38 PM

One minor point of caution, should you elect to do anything to the foam on the underside of the tub: be careful about inadvertently coating a component that wasn't meant to be insulated or reducing air space around motors, heating elements, and such or you could create a fire hazard.

11-28-2004, 04:44 PM	#1 (permalink)
Stompy Banned from being Banned Location: Donkey	How to keep heat in a hot-tub? My girlfriend's parents gave us their hot tub, and during the winter months, the bastard runs our electric bill up like you wouldn't believe.. two consecutive months last year had it up towards $150 (ours is normally $80, max). I know the top sucks.. it's really old, one of those brown "fold-in-half" type lids. It actually broke on us recently, so there are two half-lids resting on top of the tub. I heard about these little thermal covers that lay on top of the water itself that keep most of the heat in, and when used with a good lid, insures that you aren't wasting energy. I can find several on google, but I'm not sure how good they are or if they actually work wonders. Does anyone have experience with these, or does anyone have any specific models/brands of covers (thermal or otherwise) they use that keep the heat in? __________________ I love lamp.

12-04-2004, 09:12 AM	#3 (permalink)
Stompy Banned from being Banned Location: Donkey	Sweet, thanks a ton! I'm gonna be going out today to check out some covers at a spa shop around here. That, in conjunction with the thermal cover, should definitely do the trick! __________________ I love lamp.

12-05-2004, 05:25 PM	#5 (permalink)
Hard8s Addict Location: Wherever I am!	Also check that the insulation on the tub itself has not disappeared. If so make sure to put insulation back up under the tub. Blocks, spray foam, anything to help keep the water temp up. Also when you put one of those bubble covers on the water, try and make sure you don't get any water on the top of it. Any water on top is like having a hole in the cover. __________________ If ignorance is bliss, then wipe this smile off my face!

12-16-2004, 08:38 PM	#8 (permalink)
kazoo Psycho Location: Where the night things are	One minor point of caution, should you elect to do anything to the foam on the underside of the tub: be careful about inadvertently coating a component that wasn't meant to be insulated or reducing air space around motors, heating elements, and such or you could create a fire hazard. __________________ There ain't nothin' more powerful than the odor of mendacity -Big Daddy

12-01-2004, 06:03 AM	#2 (permalink)
wondash Psycho	I'd suggest three things; 1) Buy a new spa cover. Covers only last about 5 years. After that they tend to sag (or worse, rip in half). Since we're also in the market for a new cover, I've checked out some web sites. Most charge between $250 and $350 for a decent cover (up to 8'x8'). For a small extra charge, you can increase the foam density which will increase in the R factor. Check out Factory Direct Spa Covers or Poolandspa.com. 2) Buy a Thermal Cover. It won't work wonders, but every bit of heat retention helps. They're cheap, and some online sites may throw it in for free when you purchase a hard cover. It doesn't really matter where you buy it from, they're all the same. Basically it's just a heavy duty version of bubble-wrap. Keep the bubble side up. They only last a couple of years, then the plastic tends to break down. 3) Don't keep the spa at full temp (100-102) unless you plan on using it two or more times a week. This will save you the most $$ on your electric bill. Lower it to around 80 degrees (or put it in econo mode). Most spa's can increase the temp from 80 to 100 in about three or four hours (depending on how cold the outdoor temp is). This means you need to set it to full temp at dinner time, so it's ready to use later that evening. Hope this helps. It worked for us.

12-04-2004, 09:11 PM	#4 (permalink)
noblejr Crazy Location: Atlanta	If you want a big project, you could build a gazebo with removable insulated walls that you use in the winter, and put them away in the summer to have a nice open gazebo. It's a bit much, but will probably pay for itself in a few winters of heat savings.

12-07-2004, 05:55 AM	#6 (permalink)
wondash Psycho	noblejr and Hard8s both have good suggestions!

12-16-2004, 01:02 PM	#7 (permalink)
c172g Crazy Location: Michigan	We had a jacuzzi tub at our last house. There isn't anything you can do but budget a dollar a day for running the thing. We tried everything. In the summer, it obviously doesn't take much to keep it warm (plus in 80 degree weather, 102 is probably just fine). In the middle of winter, our power bill was the same as yours, even with a new thermal cover, about $150 or so per month. We kept ours at 104 & would turn it to 106 at about 8 every night, by the time the kids were in bed at 10 it would be 106. When we got out we'd turn it back down a few degrees. We live in northern Michigan & that's just the expense of having the toy.