Hi All,

I'm just about ready to pull the trigger on a LMLM and wanted to re-check my water to make sure it's suitable.

Using the popular API test kit, my filtered central NJ tap water is showing 35.8 PPM KH (2 drops to change color) and 71.6 PPM GH. From my limited knowledge of water chemistry I wouldn't expect scale, but is my alkalinity slightly low, making the water potentially corrosive?

There is also the resolution of the test kit to consider, so it might be worth doubling the sample size to increase resolution per drop. The water is filtered first through a whirlpool sediment filter (WHELJ1) and then through a plumbed in water cooler using an activated carbon Everpure 2H-L Water Filter.

I've been using an NS Oscar II with this water for the past several years with no visible issues, although I haven't inspected the boiler in some time.

Thanks

EDIT: Forgot to ask if I should also test for Chlorides somehow as from what I understand they can cause pitting in a stainless boiler.

I would start by checking out LM's guidelines for water quality:

https://www.lamarzoccousa.com/wp-conten ... ations.pdf

They also have a pretty extensive blog on water quality and their machines:

https://home.lamarzoccousa.com/water-fo ... -machines/

I use bottled Crystal Geyser water with my Linea Mini and it's the easiest option for me. The Linea Mini has been a pleasure to use... a great choice!

SamBousak wrote:Using the popular API test kit, my filtered central NJ tap water is showing 35.8 PPM KH (2 drops to change color) and 71.6 PPM GH. From my limited knowledge of water chemistry I wouldn't expect scale, but is my alkalinity slightly low, making the water potentially corrosive?

Two drops puts you close enough to the typical recommendations for alkalinity.

SamBousak wrote:There is also the resolution of the test kit to consider, so it might be worth doubling the sample size to increase resolution per drop.

Yes. Find a vial or container that holds a 10 ml sample, then you would have about 27 ppm KH at three drops and about 36 ppm at four drops giving you reasonably good precision about whether you are at or near the typically recommended 40 ppm (as CaCO3) alkalinity.

SamBousak wrote:The water is filtered first through a whirlpool sediment filter (WHELJ1) and then through a plumbed in water cooler using an activated carbon Everpure 2H-L Water Filter.

Good choice. That system has no WAC resins that you see in some charcoal pitcher filters, so it does not reduce alkalinity or acidify.

SamBousak wrote:Forgot to ask if I should also test for Chlorides somehow as from what I understand they can cause pitting in a stainless boiler.

Chloride ion is a very important consideration because if high it can cause corrosion in brass and copper as well as stainless steel. And it's not easily filtered. Your La Marzocco guidelines suggest using a reverse osmosis system with remineralization if your chloride in level runs above 30 mg/L. You can get drop titration test kits for chloride, but your best bet is usually to see if your water utility can provide numbers. If it's not in an online quality report you can often contact them for that info. Make sure they know you want chloride and not chlorine numbers.

So some interesting results after testing again (original tests were several months ago):

Alkalinity seems to be zero (or less than minimum ppm indicated by one drop). This is a corrosion concern.

TDS was the same. Also I did check the water report, and a chloride range is given from 28ppm to about 70ppm, which is also a concern.

I'm glad I looked into this further before the new machine. I might end up with RO down the road, but for now I'll stick with rpavlis water or bottled Poland spring recommended by LM.

The next step is probably to open up the Oscar II to see if there's any visible corrosion, and probably drain the boiler as it's long overdue.

Thanks for all the help.