Flat thermometers

[genelong]

Does anyone know of where I can buy stick-on liquid crystal thermometers for hot tubs - similar to the little stick-on thermometers they make for fish tanks.  They stick to the side, and have squares or dots for each degree, which turn light or dark depending if the temperature is past that degree.  

If you don't know what I'm talking about, an example of what I want is at http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/21141/cid/229
except I need it to measure hot tub temperature ranges, like 98-108, or something like that.

Thanks

Gene

[Brewman]

Those stick on thermometers for aquariums stick on the outside of the glass, at least ours does.  
I doub't they'd stick on the inside- the water and heat from the spa might work them loose.  

Sticking the thermometer to the outside of a spa wouldn't get you the water temperature anyway, it would give you the temperature of the spa cabinet surface.  

Are you trying to set up something to read the spa water temperature without having to lift the cover?

[drewstar]

Those are liquid crystal thermometer strips, and it's my understanding they are also used in homebrewing. (Google can help you find an on-line source).

I'm curious where would you mount this? Aren't they usually mounted on the outside of glass?  You'd have to stick it  on the hot tub shell?  (Not sure how well the adhesive would hold up with hot bubbley water).

Also they are not that accurate and have a limited life.

Why not go with a more conventional thermometer? Or pehaps if you don't want something bulky, or breakable an electronic one with a probe?

Anyhow, Google, It's your friend.

[drewstar]

IF checking the temp without lifiting the cover something like this would be neat:

http://www.nu-temp.com/601.htm

[wmccall]

Those crystal ones aren't usually real accurate. I can tell the temp of a spa within one degree usually. Shall I come over?  

[genelong]

I'm looking for this because I really hate floating thermometers - they are constantly bobbing against someone.  I'm picturing something manufatured specifically for hot tubs, to stick on the inside of the tub, just below water level, with very large digits, so that you can see at a glance what the temperature is from anywhere in the tub.

It would also be nice so that when the thermostat gets stuck (as mine does from time to time), you can avoid getting scalded tootsies.

Seems like an obvious need to me, I'm just assuming someone's already thought of it, but maybe not.

[wmccall]

I've seen people tie thermometers down so they can't float around.  

[Brewman]

The control panel of my spa gives a temperature reading.  I take it yours doesn't?

Maybe some suction cup thing would work, not sure how well it would stick if you have a pebbly surface shell.

[jsimo7]

IF checking the temp without lifiting the cover something like this would be neat:

http://www.nu-temp.com/601.htm

I just ordered one of the NU600 air/water wireless thermometer from this website that drew had the link to. I will do a review on it when I get it up and running.

[drewstar]

I'm not a fan of the floating thermometers either. However, you can get a decent quality thermometer that doesn't float.

The one Ihave for my swimming pool is heavy and doens't float. It sinks like a stone: Tie a string to it:

Check out the S.S ones here:

http://www.poolstore.com/store1/welcome.html?accessories/Thermometers/Thermometers/index.html

[Chas]

The thermometers with the gradations etched on the glass are the only ones which are trustworthy enough to use for a spa. Of course, you don't want glass in the spa unless it is contained in a metal tube with a stout plastic front. BUT any thermometer which lives in the spa full time will be knocked out of accuracy in a short time. Most pool and spa thermometers have the numbers and gradations printed on a plastic card behind the glass. The card and the glass are stuck together with hot glue or something similar. The glue lets go, the card and/or the glass move, and I get a call saying, "My hot tub jumps 35 degrees while I'm sitting in it. Come fix it now!!"

I sell a pocket thermometer - with the gradations etched onto the glass - and I suggest finding a place near the spa where it can be kept. It takes just a few seconds to "take the temperature" of the spa and then return it to its home. The one I sell is a HotSpring part number, meant for technicians to carry for repair work.  They work very well, have a metal sleeve for storage, and cost around $19. You can get the same one, or you can get a similar one from scientific supply houses, darkroom (photo) supply houses, general supply houses, etc. A medical thermometer works.


Radio Shack used to sell an electronic dual-temp unit for about $13 which was just perfect, but they have changed the design and added a bunch of features, so somebody will have to do a 'wet test' on the new ones and report back for us.

Go to and search "Thermometers."

[drewstar]

Why do many tubs not have dual temp displays? (show actaul water temp and the set water temp?)

My tiger river only shows the set temp  and it seems like a lot of tubs out there don't have the dual temp display. Why? It can't really be that exspesive of an option and it seems to be a great feature. I wish I had it.

[stuart]

Why do many tubs not have dual temp displays? (show actaul water temp and the set water temp?)

My tiger river only shows the set temp  and it seems like a lot of tubs out there don't have the dual temp display. Why? It can't really be that exspesive of an option and it seems to be a great feature. I wish I had it.

 

Most brands show both set temp and actual temp...I was hoping that Watkins changed that when they did all of the cosmetic upgrades but I guess not.

[Chas]

I used to do warranty work for Sundance and few other makers who chose to include an actual temp display. In the old days, you could make a very minor adjustment if the display was off a couple of degrees.

I did a lot of those calls.

The trouble was, the same adjustment would change the actual temperature in the tub - if I goofed, the customer could end up with a spa which went to 108 when it was set for 104.

It is my understanding that UL required the removal of those adjustment possibilities in newer tubs - so the temperatures are now locked in. If it does somehow wander off, the temp sensor must be replaced, and if that doesn't fix the trouble, the circuit board gets replaced. But most temp sensors are only accurate to a degree or two in the first place! So tubs with the display - like Caldera for example... can only be counted on to be within two degrees, and there is no adjustment to fine tune it.

As a result, many companies have decided to not include a current temp display in the programming of their units.

And one more item of interest: many tub makers will not do a warranty service call if the tub is off by just one degree. They know that sending a service tech out to replace the temp sensor could very well make it two degrees off. Also - they know that many people don't have a accurate thermometer to begin with - hence the topic of this thread - so the tub may actually be spot-on and the customer's thermometer off. I have had that happen more times than I care to recall.  Let me be clear: what I am talking about is when you have to set the tub to 100 to get an actual 102, but the tub stays reliably at that temp and the only problem is knowing that you have to keep your setting at 100. If the temp changes or wanders, a service call happens right away.

[stuart]

I used to do warranty work for Sundance and few other makers who chose to include an actual temp display. In the old days, you could make a very minor adjustment if the display was off a couple of degrees.

I did a lot of those calls.

The trouble was, the same adjustment would change the actual temperature in the tub - if I goofed, the customer could end up with a spa which went to 108 when it was set for 104.

It is my understanding that UL required the removal of those adjustment possibilities in newer tubs - so the temperatures are now locked in. If it does somehow wander off, the temp sensor must be replaced, and if that doesn't fix the trouble, the circuit board gets replaced. But most temp sensors are only accurate to a degree or two in the first place! So tubs with the display - like Caldera for example... can only be counted on to be within two degrees, and there is no adjustment to fine tune it.

As a result, many companies have decided to not include a current temp display in the programming of their units.

And one more item of interest: many tub makers will not do a warranty service call if the tub is off by just one degree. They know that sending a service tech out to replace the temp sensor could very well make it two degrees off. Also - they know that many people don't have a accurate thermometer to begin with - hence the topic of this thread - so the tub may actually be spot-on and the customer's thermometer off. I have had that happen more times than I care to recall.  Let me be clear: what I am talking about is when you have to set the tub to 100 to get an actual 102, but the tub stays reliably at that temp and the only problem is knowing that you have to keep your setting at 100. If the temp changes or wanders, a service call happens right away.

Both of my Marquis have been with 1 degree of what they read year round....

Out of thousands of spas we have out there with the display reading the actual temp I don't get service calls on the spa not reading correct unless it reads dramatically different and has a sensor problem or something.

If that happens we are happy that the topside let us know....Wanna bet that HotSpring changes in the next few years to an actual temp read out?