Water maker - why discard intial water?

[Tellie]

Originally Posted by Bruce Beard

It flushed just fine. Lots of fresh water that got to everywhere it was supposed to for the correct amount of time. I always felt it was a function of the salt water left inside the filter housings after the flush. There is always some left in the housings at the bottom no matter how long the flush lasted.
I was initially concerned but Spectra assured me it was normal for my system.
Something must have been happening as the membrane was still working just fine at 11 years old. No degradation of water volume or quality.
Every time I changed a filter on that system I was amazed by the foul smell.
Interestingly, the US Watermaker 800 GPD watermaker on our new boat never smells the way the Spectra machine did.
Even when filters clog and the machine is stopped to change them without a flush they never smell that bad...

I'm gonna kick that horse one more time and the sway back may just kick back but, Spectra is wrong.

[lordgeoff]

Originally Posted by Tellie

Not to beat a horse here, but as Dulcesuenos correctly points out, If the flush system is set up correctly it will flush the filters and lines as well so there is no salt water left in the system to go bad. The rotten egg smell is hydrogen sulfide gas. This gas can seep by a salt water membrane and make the water smell bad. This is why a proper flushing is important. Once you have a system that starts to bio-foul, and that's what this is all about, it can set in and be tough to get out without a chemical cleaning. It's not difficult to set a fresh water flush system up correctly, but it should most definitely be done. A consistently fouling system can and will lead to other issues and costs as well.

Here is a solution Del. You can spend your Friday sundown backwashing your water maker and I’ll sip cold beers on the back deck.
I’m happy with that if you are?
BTW my Spectra runs as good as day one. Never had to do a chemical wash
and the horse died....

[Olddan1943]

Originally Posted by lordgeoff

The Desal goes into my 25Lt containers. When they are full I turn the Desal off.
I then go to the fridge and snap the top off a beer...........
Repeat every Friday just before sundowners.

25Lt containerS? You must have a huge fridge.

[a64pilot]

Originally Posted by lordgeoff

Here is a solution Del. You can spend your Friday sundown backwashing your water maker and I’ll sip cold beers on the back deck.

I’m happy with that if you are?

BTW my Spectra runs as good as day one. Never had to do a chemical wash

and the horse died....

It takes less than 5 min to fresh water flush mine, work wise it’s the flip of two levers on my panel, flip a switch, go to the fridge get that beer, return, turn off switch, flip one lever.

There is no taking anything apart or climbing into tight places etc.

[Olddan1943]

Originally Posted by Olddan1943

25Lt containerS? You must have a huge fridge.

Then you have a beer and recycle that?

[Captain Bill]

I have to disagree with you Tellie. The hydrogen sulfide smell is from the anaerobic decomposition of biological organisms in the seawater and trapped in the raw water filters. More specifically the decomposition of sulfur containing proteins in those organisms. Fresh water flushing will kill most of these organisms that are not already dead but will do nothing to prevent decomposition of those organisms. The only way to prevent the build up of hydrogen sulfide in the system is to clean the raw water strainer and remove the pre-filters. A full fresh water flush will only remove the organism in the water, not in the filters. The number of organisms in the sea water in a non-running system is inconsequential compared to the amount trapped on the filters after a few hours of running.

[lordgeoff]

Originally Posted by Olddan1943

25Lt containerS? You must have a huge fridge.

Putting water in a fridge?
That would be as weird as putting food in a fridge.
Fridges were invented to keep beer cold.

[Olddan1943]

120 vt or 12 vt?

I opted for the 12vt. Why start the gen when the ME is running?

[lordgeoff]

Originally Posted by Olddan1943

120 vt or 12 vt?

I opted for the 12vt. Why start the gen when the ME is running?

Yes my system is 12V also. Uses only a few Amps.
Not sure if the penny dropped with the other lads.
My system is set up to back wash and either send the desal product to my water tanks or to other storage.
I choose to store the desal water separately from the built in tanks (1,000Lt) as the water in those tanks is a mixture of supply from marinas and town dock so the quality cannot be assured. The tank water would almost certainly have chlorine which is terminal for the watermaker if not filtered out by a charcoal filter when used for backwashing. My system has a charcoal filter btw.
Water Makers love to be used regularly. Whether I need water or not I run the water maker every Friday (or earlier if needed).
We generally travel for 5-6 months so the water maker gets regular use. At the end of the season I do a complete backwash using my own desal water as the flushing product prior to pickling with Glycol for the winter.
I am very pleased with the Spectra unit. It has been faultless for 5 years.

[Olddan1943]

Originally Posted by lordgeoff

Yes my system is 12V also. Uses only a few Amps.
Not sure if the penny dropped with the other lads.
My system is set up to back wash and either send the desal product to my water tanks or to other storage.
I choose to store the desal water separately from the built in tanks (1,000Lt) as the water in those tanks is a mixture of supply from marinas and town dock so the quality cannot be assured. The tank water would almost certainly have chlorine which is terminal for the watermaker if not filtered out by a charcoal filter when used for backwashing. My system has a charcoal filter btw.
Water Makers love to be used regularly. Whether I need water or not I run the water maker every Friday (or earlier if needed).
We generally travel for 5-6 months so the water maker gets regular use. At the end of the season I do a complete backwash using my own desal water as the flushing product prior to pickling with Glycol for the winter.
I am very pleased with the Spectra unit. It has been faultless for 5 years.

If you are afraid of the chlorine, use that first and discarding the first water saved in the boat's tanks as a rinse.

I have a Spectra MPC-5000 Mk2 controller of a Newport 400 Mk 11-Z. I have yet to use it so it is in factory condition. I have a really really long water hose.

How many spare filters to you carry onboard?

The installer said, "everything is automatic." I still had him install a small spigot, the out-let is aimed to the bilge. I wanna taste the water first. Do you keep a TDS meter on board? The installer said it was unnecessary.

Anyone go to the added options of a UV light on the product outlet before it goes to the water tanks?

The installer asked if I wanted 12vt or 120vt..... My rational for the 12vt included but not limited to, ME running charging the batteries, I have 2X135 solar panels or the generator. I think I have the power to run the water maker, pretty much solid or perhaps, over-kill. SMILE

Ah, one more thing. I carry some Peroxide "bleach" on board. Add that to the water tank and it is supposed to destroy the chlorine in the water. Thank you Publix grocery store.

[Tellie]

Originally Posted by Captain Bill

I have to disagree with you Tellie. The hydrogen sulfide smell is from the anaerobic decomposition of biological organisms in the seawater and trapped in the raw water filters. More specifically the decomposition of sulfur containing proteins in those organisms. Fresh water flushing will kill most of these organisms that are not already dead but will do nothing to prevent decomposition of those organisms. The only way to prevent the build up of hydrogen sulfide in the system is to clean the raw water strainer and remove the pre-filters. A full fresh water flush will only remove the organism in the water, not in the filters. The number of organisms in the sea water in a non-running system is inconsequential compared to the amount trapped on the filters after a few hours of running.

OK , trying not to get too technical but you are correct. To a point you are correct that you won't remove all organisms, not to mention you're still dealing with the organisms living in your fresh water tanks and plumbing that can do the same thing. It's a matter of slowing down the inevitable long enough that your system can sit for a few days without creating a problem of bad smelling product. But a proper fresh water flush will remove and retard enough that this decomposition becomes minor enough to stop any noticeable smell or foul taste in the product water on first start up. You give me a proper watermaker that stinks every time on initial start up and less than 30 minutes later it never will again.

[Tellie]

Originally Posted by Olddan1943

If you are afraid of the chlorine, use that first and discarding the first water saved in the boat's tanks as a rinse.

I have a Spectra MPC-5000 Mk2 controller of a Newport 400 Mk 11-Z. I have yet to use it so it is in factory condition. I have a really really long water hose.

How many spare filters to you carry onboard?

The installer said, "everything is automatic." I still had him install a small spigot, the out-let is aimed to the bilge. I wanna taste the water first. Do you keep a TDS meter on board? The installer said it was unnecessary.

Anyone go to the added options of a UV light on the product outlet before it goes to the water tanks?

The installer asked if I wanted 12vt or 120vt..... My rational for the 12vt included but not limited to, ME running charging the batteries, I have 2X135 solar panels or the generator. I think I have the power to run the water maker, pretty much solid or perhaps, over-kill. SMILE

Ah, one more thing. I carry some Peroxide "bleach" on board. Add that to the water tank and it is supposed to destroy the chlorine in the water. Thank you Publix grocery store.

Call me when you do start it up for the first time and I'll walk you through the proper fresh water flush set up for your NP400, and yes, I absolutely recommend a simple hand held TDS meter. You can't properly set up the fresh water flush on your NewPort400 without one.

[Palarran]

We run our water maker daily and don't flush it or reject the first part of the water. It takes less than 30 seconds to produce water less than 300ppm and it runs for an hour. The dilution is so great that the salt content in the first start of the cycle is negligible. I also have to agree with Captain Bill that the smell is from the filters, specifically for us the 20 micron filter. Those filters cost about zero so we just change them often. The 5 micron filter we change about once per month.

It's really crazy how complicated some of these water makers are. Ours is a simple flip of a switch, turn a knob clockwise until a needle hits 800 psi, check the output gpm, make as much as you want, turn the knob counter clockwise, and turn off the switch. We've made lots of water this way, probably 25,000 gallons and no one has ever complained about the taste or gotten sick from drinking it.

It's interesting about the TDS meter - does anyones readings ever change? Mine runs between 250 and 300 period. Never more or less.

[SV THIRD DAY]

Originally Posted by Tellie

Not to beat a horse here, but as Dulcesuenos correctly points out, If the flush system is set up correctly it will flush the filters and lines as well so there is no salt water left in the system to go bad. The rotten egg smell is hydrogen sulfide gas. This gas can seep by a salt water membrane and make the water smell bad. This is why a proper flushing is important. Once you have a system that starts to bio-foul, and that's what this is all about, it can set in and be tough to get out without a chemical cleaning. It's not difficult to set a fresh water flush system up correctly, but it should most definitely be done. A consistently fouling system can and will lead to other issues and costs as well.

Bingo!!!

Don't except a water maker set up where you smell hydrogen sulfide gas every time you start up the watermaker. It's shortening the life of your system and telling you something is wrong. Something is either wrong with how you are maintaining it or how the fresh water flush system is set up one way or the other you need to deal with it now or pay for it later.

Another important thing never judge the quality of your water maker water based on taste alone, you must use a TDS meter either a handheld or an inline meter. They're like 25 bucks online so don't be cheap, get one and verify that the quality of your water is good don't hurt your kidneys by drinking 1300 PPM water but thinking it's still tastes good because you can't taste the salt.

[Caroline Joan]

Thanks for all your replies.
I'm so much wiser on my water maker now.

I'll continue to dump the first few minutes of water produced & buy a tester for the water output.

No sulphur smells my end - well not from the water maker anyway!