PLA choice for hot tubs?

I came into a free hot tub that needs a few parts. Manufacturer has gone out of business, so I am looking for options. Anyone have experience with printing/using parts for use in a hot tub? I am replacing an air valve unit handle. Will be mounted outside the water but will be under the cover and exposed to chlorine/bromine fumes over time. Anyone know if PLA can handle this? ABS or other?

I’ve already printed the air valve unit to test, but wanted to know if anyone has tried this already.

ABS can handle it, UV exposure and Chlorene may damage it over time similar to most other plastics. Polycarbonate would work better, but is more difficult to print. PLA would not be suitable chemically or from a temperature standpoint.

I agree with piercet and I would just like to add a few more.
Alloy910 and 680 are nylons that, by definition, are quite inert to chemicals and might do the trick for you. Plus, they can withstand some high temps. I’ve tried the 910 and I love it. Use “Wolfbite Mega” from Airwolf3D to help with adhesion. Works wonders compared to gluesticks.
Also, the BluPrint from Taulman again, is a co-polyester designed to withstand boiling water for almost 5 hours according to their website:
Any part that will need to be placed in boiling water for preparation.
BluPrint can sustain boiling water for 5 continuous hours. Clarity will be lost after 2 hours to a dull haze. Structure will be maintained.
”. Unfortunately doesn’t say anything about chemicals.
Hope these help

Good tips… Thx guys… Given it cost me pennies to print this, I’m going to take a gamble on the PLA and will report back when I get the tub working and it has had some time. At least it wont be under water. It will be the fumes when covered that will get it I think.

Since you want to give it a shot with the PLA, how about you try the new HiTemp PLA that’s been out lately? At least, with this, you’ll have the PLA print-ability you’re familiar with and the needed high temp resistance and you won’t have to worry about the part getting too soft and coming apart making a mess in your tub.
So far I’ve seen Protopasta and Makergeeks having that high temp version of PLA, where you just put the finished part in the oven @90-100degC for about one hour (anneal process) and then it’s good for up to 110-125C.

@PlastiBots looks like it’s been a few years, if by any chance you get a notification of this post, it’d be really great to hear how you got on with this?

Lol thanks for the reminder! Turns out PLA worked quite well. It lasted until early 2019 until it cracked. The steam/chemicals caused the black to turn gray, but it held together quite well. It was also constantly wet - but not submerged. I’ve been meaning to re-print another copy, but haven’t gotten around to it.

That’s awesome, thanks!
I just finished the first “prototype” print of an assembly + adapters that lets me add an inline filter to a hot tub pump inlet and attach a hose to it for a pool vac. It works absolutely brilliantly, but at something like 35 to 40 hours of print time and the best part of half a spool of PLA, I figured I’m going to see how long it holds out before thinking about reprinting in another material!
Might still make a few refinements and upload to thingiverse though…
Cheers @PlastiBots !

Something to keep in mind that the valve handle I made was for an external component for the handle of a valve. Just be cautions of putting something inside a pump assembly that has to deal with water turbulence and pressure. If it breaks apart it could cause damage to the pump unit or heating core.