Temperature Accuracy

[nlittle]

Just curious if anyone else has taken their tubs temp?  I threw a pool/spa thermometer in my HS at 104 and it reads about 110!    I think it is probably the thermometer itself but phew that is hot!

[svspa]

I have a little sharky thermometer in the tub. Water temp always reads 1 degree hotter than the display on my Jacuzzi.

Steve

[hottubdan]

Pool/spa thermometers are not reliable.  If you really want to check temp use a digital thermometer.

[Chas]

HotSpring tubs shut down at 108 or above.

I suspect your pool thermometer is off - most of them are.

 8-)

[Chad]

Pool/spa thermometers are not reliable.  If you really want to check temp use a digital thermometer.

Thanks for the FYI hottubdan.
I was going to purchase one of those but not any more. I'll spend the extra bucks and get a digital one.

[drewstar]

Just curious if anyone else has taken their tubs temp?  I threw a pool/spa thermometer in my HS at 104 and it reads about 110!    I think it is probably the thermometer itself but phew that is hot!

I have a pool thermoeter that I've used to double check the temps in my hot tub  and they are both consitent with each other within maybe 2  degrees. Good enough for me.

 I am mostly concerned about the temps when I am refilling the spa.  It's possible on the Tiger River tubs (and I suspect many other tubs) to trip the circ pump when you flip the power back on and it wont heat.  Since the digital temp display only goes down to 84 (?) or so, and Watkins tubs don't show "Actual" temp; just 'Set" and an indicator telling you it's reached the set temp, it can be difficult on a refill to tell inintally if it's heating.  I don't wont to wait several hours and find it's still not heating.    Tossing in the a pool thermometer helps me idendtify if everything is working.

Yes, I could get into the tub and put my hand over the heat drain, but jumpinng into 45 degree water isn't my first choice.

[txwillie]

I fed the neighbors cats a few weeks back while they were on vacation. They have an old Morgan spa with non-digital controls. Was gonna try it out, so I bought some dichlor shock and dosed it real good. The temp was low, so I cranked it up. Just has a dial that shows cool/warm/hot. Came back the next day, opened it up and the floating thermometer showed 114 F. I believe it. Could not get into the spa. I turned it back down and never opened it up again.

txwillie

[drewstar]

I fed the neighbors cats a few weeks back while they were on vacation. They have an old Morgan spa with non-digital controls. Was gonna try it out, so I bought some dichlor shock and dosed it real good. The temp was low, so I cranked it up. Just has a dial that shows cool/warm/hot. Came back the next day, opened it up and the floating thermometer showed 114 F. I believe it. Could not get into the spa. I turned it back down and never opened it up again.

txwillie

And the neighbors come home to find thier electric bill has gone up more than the mortgage payment and the cat collapesed form mal nutrition. .

[lskarp]

Remind me not to have TX willie over to house sit!!

[txwillie]

Remind me not to have TX willie over to house sit!!

What? They said go ahead and use it. In the summer, they offer use of the pool too. How was I to know that the tub was even capable of getting the temp so hot? It was only that elevated over one night. Sheeze.....

txwillie

[Steve]

There's differing qualities of thermometers out there but in my experience, most spas are within a degree or 2. The biggest issue with accuracy of a top side control is determining if the temperature sensor within the spa is pushed in as far as possible to gain the most accurate reading. If the sensor is back an inch, it's reading a cooler temp and therefore heating the water to a higher degree than shown on the display.

This is also the way to obtain water temps higher than 104 if desired though I don't recommend it...

Steve

[Chas]

Many Pool thermometers have the gradations printed on a card. Some are just held to the glass vial with a pair of staples, others use that and gule, still others are clamped together by the housing itself.

The point is, that over time the glas and card can shift in relation to each other, and that makes them useless.

If you have a good technical thermometer with the gradations etched into the glas itself, you have a better chance, but I still have seen those go bad if they are left in the tub hangin' on a string or floating in the skimmer.

I use a tech thermometer which I order from HotSrpings under a 'tool' part number. It comes with a little metal enclosure that looks about like a pen. Has a pocket clip and the thermometer is held in with a screw cap. Seems to last a few years and then I have to replace it. Not meant to be left in the tub - I have sold a few to customers who hung it on a nail near the tub, or kept it carefully with their tub supplies, and used it to check the temp and then put it safely away.

These:

Are not generally any good.

 8-)