RO versus Distilled H2O

[Crusty Chief]

I kinda tired of carrying around several gallons of distilled water for my Rolls battery bank. Man are they thirsty bugers. I measured the TDS (Total Dissolved Solids) of both and the RO is less than the distilled.

Wondering if anyone else uses RO water from the water maker to top off the batteries? Any draw backs?

Cheers

 

[Nomad Willy]

Anything but distilled is most likely to have minerals ect ect.
I don’t use anything but distilled in the batts and cooling system.

 

[dhays]

I kinda tired of carrying around several gallons of distilled water for my Rolls battery bank. Man are they thirsty bugers. I measured the TDS (Total Dissolved Solids) of both and the RO is less than the distilled.



Wondering if anyone else uses RO water from the water maker to top off the batteries? Any draw backs?



Cheers

Now that you are down south, if you are running AC you would have a source of condensate that you could use for your batteries. You just need to capture the condensate from the AC units.

 

[DavidM]

I kinda tired of carrying around several gallons of distilled water for my Rolls battery bank. Man are they thirsty bugers. I measured the TDS (Total Dissolved Solids) of both and the RO is less than the distilled.

Wondering if anyone else uses RO water from the water maker to top off the batteries? Any draw backs?

Cheers

Why are they so thirsty? When I cruised full time I would add water only 2-3 times each year to my house bank made up of Costco GC batteries. I used about 1/2 quart each time I filled 6 GCs.

I would take a look at your battery charger. Maybe it is set too high on float so it boils out too much water.

RO water is about as good as distilled as your measurements indicate.

David

 

[RT Firefly]

Greetings,
Mr. CC. In a previous life, the distilled water taps in the various research labs were, in fact, reverse osmosis water so fill you boots (batteries). I suppose it depends on the membranes used for your water maker as compared to lab set ups but if TDS are less, I'd say you're good to go.

 

[Crusty Chief]

Why are they so thirsty? When I cruised full time I would add water only 2-3 times each year to my house bank made up of Costco GC batteries. I used about 1/2 quart each time I filled 6 GCs.

I would take a look at your battery charger. Maybe it is set too high on float so it boils out too much water.

RO water is about as good as distilled as your measurements indicate.

David

The Rolls are huge batteries, 820 amps each. Which gives me roughly 400 Amps of use, but I try to limit draw to 275-300 max. These are the only batteries that are not sealed and are in the engine room, so they are susceptible to the engine room heat. They just took almost a gallon for both batteries, which is the norm over the last few years and was almost 110 days ago since last top off.

But thanks for the idea, ill put that task on the list with the other 40 items, LOL!

 

[Crusty Chief]

Now that you are down south, if you are running AC you would have a source of condensate that you could use for your batteries. You just need to capture the condensate from the AC units.

We dont have AC on Pairadice, but its on the list. And I’m not sure the Genny would run everything on the boat, its only a 8KW, so that might have to be upgraded also to handle 3 AC units.

Just another bunch of boat bucks, that’s all.

 

[Chrisjs]

While RO water from a quality installation may approach TDS of distilled it is never as good, because distilled should contain zero ppm of anything except H2O. This is especially so when the RO water is produced from a boat system desalinating seawater.

 

[dhays]

We dont have AC on Pairadice, but its on the list. And I’m not sure the Genny would run everything on the boat, its only a 8KW, so that might have to be upgraded also to handle 3 AC units.

Just another bunch of boat bucks, that’s all.

Thats right, it is only money....

 

[ksanders]

I kinda tired of carrying around several gallons of distilled water for my Rolls battery bank. Man are they thirsty bugers. I measured the TDS (Total Dissolved Solids) of both and the RO is less than the distilled.

Wondering if anyone else uses RO water from the water maker to top off the batteries? Any draw backs?

Cheers

I use RO water for my house bank.

Works just fine. My house bank is 8 years old, and three of those years it only has gotten RO water. PPM of this typically runs around 120

 

[rslifkin]

We dont have AC on Pairadice, but its on the list. And I’m not sure the Genny would run everything on the boat, its only a 8KW, so that might have to be upgraded also to handle 3 AC units.

Just another bunch of boat bucks, that’s all.

Depends on what size your A/C units are and what your expectations are for simultaneous equipment use on generator power. I can run all 3 of mine (2x 10k BTU + 1x 16k BTU) on my 6.5kw gen and sit steadily just under 75% load, which leaves enough headroom for the battery charger, water heater to cycle, etc. If I need to use the electric stove or anything else major, I have to do some load management, but it's rare that I have a reason to run all 3 A/Cs and use other high power devices at the same time on generator power.

 

[Montenido]

According to the Trojan website, if your RO water has LESS than 100ppm dissolved solids it is fine to use in FLA batteries.

https://www.google.com/url?sa=t&rct...ies_0612.pdf&usg=AOvVaw0vxRnS2-pSfDMKMQb89lQ3

I also use a fair amount of distilled water so I am going to check my watermaker product ppm. Also, I might put a jug under my AC drain line and check that for dissolved solids as well.

Cheers, Bill

 

[Chrisjs]

I would go back to one of the earlier questions asked about why the batteries need so much water.
I had 2 Rolls 8Ds as part of my housebank (plus 2 FullRiver 8D AGMs).
The Rolls batts did not need a lot of water. They were in the ER of a Selene 47, just like yours. I would check your charging system for overcharging, and consider fitting a smart(er) regulator. Worst case, try some Water Miser battery caps.

 

[ksanders]

I would go back to one of the earlier questions asked about why the batteries need so much water.
I had 2 Rolls 8Ds as part of my housebank (plus 2 FullRiver 8D AGMs).
The Rolls batts did not need a lot of water. They were in the ER of a Selene 47, just like yours. I would check your charging system for overcharging, and consider fitting a smart(er) regulator. Worst case, try some Water Miser battery caps.

I am pretty sure he is a liveaboard/stayaboard and probably anchor’s out a lot.

Also he went almost 4 months between topoffs.

Seems like a reasonable water usage.

 

[Lepke]

RO from fresh water is usually zero ppm on my system. RO water from sea water is about 200 ppm. I use RO water for batteries. I use 8d batteries and before I changed to a Sterling charger, used several gallons a month. On the alternators water use was light.
My 8Dds usually last about 8 years and 8Dcs go about 10. Dyno batteries.

 

[Ken E.]

Crusty, I use distilled water my batteries because it's readily available but I'd have no problem using WM water in them. I usually see about 100 ppm of TDS when I measure it.

 

[Gordon J]

I’d think twice

Greetings,
Mr. CC. In a previous life, the distilled water taps in the various research labs were, in fact, reverse osmosis water so fill you boots (batteries). I suppose it depends on the membranes used for your water maker as compared to lab set ups but if TDS are less, I'd say you're good to go.

My to water comes on at about 150 ppm. Distilled typically much less. BTW, my tap water from the city system here in Hampton, vs is about 180ppm.

Stick to distilled.

Gordon

 

[Crusty Chief]

Ok you guys. While sitting out back here in Ensenada with a cold one and soaking up the Sun, I started a clinical test.
1) The tap water on the dock is at 820 PPM, Dont wanna drink this stuff, or even wash with it.
2) The water maker at start up was 210 PPM, after about 3 hours of running it was at 110 PPM
3) The Distilled water sample was at 120 PPM
4) The Water from the de-humidifier was at 95 PPM
5) The Budweiser from USA was 260 PPM
6) The Tecate from Mexico was 365 PPM

So after this Clinical test, I determined I need a few more Cervesa’s to accurately compile data. But for the time being, maybe just use the De-Humidifier water when I run out of distilled water first and fill a jug with water from the Water maker at the end of the run as my back up.

 

[dhays]

Ok you guys. While sitting out back here in Ensenada with a cold one and soaking up the Sun, I started a clinical test.
1) The tap water on the dock is at 820 PPM, Dont wanna drink this stuff, or even wash with it.
2) The water maker at start up was 210 PPM, after about 3 hours of running it was at 110 PPM
3) The Distilled water sample was at 120 PPM
4) The Water from the de-humidifier was at 95 PPM
5) The Budweiser from USA was 260 PPM
6) The Tecate from Mexico was 365 PPM

So after this Clinical test, I determined I need a few more Cervesa’s to accurately compile data. But for the time being, maybe just use the De-Humidifier water when I run out of distilled water first and fill a jug with water from the Water maker at the end of the run as my back up.

Great test Crusty. Nothing beats a beer and a few quiet moments to come up with some ideas.

I had wet cells on my sailboat. I would keep an empty water bottle under the drain hose from my dehumidifier and used that to top up my batteries for years. When you think about it, distilled water is water that is boiled and the steam is condensed again a cold surface and collected. Your dehumidifier (or an AC unit) has water that is condensed out of the air and collected. Same process.

 

[Comodave]

We dont have AC on Pairadice, but its on the list. And I’m not sure the Genny would run everything on the boat, its only a 8KW, so that might have to be upgraded also to handle 3 AC units.

Just another bunch of boat bucks, that’s all.

We don’t have any problem spending your money. Not at all...

 

[ksanders]

Ok you guys. While sitting out back here in Ensenada with a cold one and soaking up the Sun, I started a clinical test.
1) The tap water on the dock is at 820 PPM, Dont wanna drink this stuff, or even wash with it.
2) The water maker at start up was 210 PPM, after about 3 hours of running it was at 110 PPM
3) The Distilled water sample was at 120 PPM
4) The Water from the de-humidifier was at 95 PPM
5) The Budweiser from USA was 260 PPM
6) The Tecate from Mexico was 365 PPM

So after this Clinical test, I determined I need a few more Cervesa’s to accurately compile data. But for the time being, maybe just use the De-Humidifier water when I run out of distilled water first and fill a jug with water from the Water maker at the end of the run as my back up.

Which marina are you at? How do you like Ensenada? How is the marina?

 

[Crusty Chief]

Which marina are you at? How do you like Ensenada? How is the marina?

Hi Kevin,

We are at Baja Naval. Not the best here, (but much better than some we stayed at up North) but rent is cheaper than Coral (A resort mostly) and a lot closer to town. In fact, we are right on the Malacon. I’m told the weekends get a bit loud. The harbormaster, Victor was a Hugh help in processing the paperwork, he handles it all for us, we just pay the fee’s.
When are you planning on coming down?

 

[ksanders]

Hi Kevin,

We are at Baja Naval. Not the best here, (but much better than some we stayed at up North) but rent is cheaper than Coral (A resort mostly) and a lot closer to town. In fact, we are right on the Malacon. I’m told the weekends get a bit loud. The harbormaster, Victor was a Hugh help in processing the paperwork, he handles it all for us, we just pay the fee’s.
When are you planning on coming down?

I retire March 2021 I’ll be there this time of year.

A long ways to go from Alaska But warmth is calling my name.

 

[Crusty Chief]

Yepper!
Haven’t had the heater on in some 70 days, far cry from the PNW, even in the summer!

 

[SeaMaster101]

I’ve been cruising with my vessel for years and had to take care of 24 golf cart batteries. Talking about having gallons and gallons of distilled water with me for thousands of miles and searching for it in the South Pacific... not fun!
About distilled vs reverse osmosis RO water - distilled must have 0 ppm (parts per million) contaminants. And it does. I have measured every distilled water gallon I bought. On the other hand reverse osmosis water from marine water makers will have even in the best case scenario with new membranes about 100-150ppm. My membranes are 10+ years old and the water coming from them is about 200-260ppm. So needless to say don’t use marine Watermaker product to top your batteries unless you really need to. It is better to use some water rather than leaving them dry but that will definitely reduce the expected life. Not as much as dry battery-dry battery dies really fast!

In the labs they may be using different type of membranes for generation of distilled water with 0ppm. I know for a fact that there are different RO membranes for brackish water and salt water. Maybe there is type that gives you better product comparable to distilled water.

 

[timb7734]

Watering batteries

I have 12 golf cart batteries in the engine room, they regularly consume a gallon and a half distilled water per month, your consumption does not sound unreasonable

 

[Lepke]

If you have the opportunity to pull into fresh water and make water there, you'll find a salt water membrane will make very low tds numbers at a much lower pressure setting. Years ago with the hauling of distilled water and the cost, I decided just use watermaker water and change batteries more often, but that didn't turn out to be the case. My Dyno 8Dc & 8Dd batteries give good service at least 8 years. I use a homemade auto watering system so the plates are always covered. And since going to a Sterling charger, my water use is probably half.
Although you can make a distiller with a jacketed exhaust pipe. It's what fishermen used to do before RO.

 

[HeadedToTexas]

Very unusual for RO and distilled water to have the same TDS. You are using a conductivity meter that displays in TDS, right? Unless your distilled water is contaminated, it should be darn close to zero TDS. Rare for RO to get that low unless you are starting with very, very low TDS feedwater. Have you calibrated your meter with a very low conductivity standard?

 

[motion30]

Excatly what i was thinking. If you could run your freshwater through your watermaker it would have very low ppm

 

[HeadedToTexas]

Freshwater still has plenty of TDS. 300 ppm is not uncommon. RO should be able to take that down to 25-30 ppm or so.