Spectra watermaker questions

[SVSeaHawk]

I have a Spectra Ventura 150 that came with the boat two years ago but was nonfunctional. The caps on the membrane were blown off I presume from freezing in Maine where I got it.


I repaired this and got it working with a lot of help from T.J. down in Florida (business name I can't remember). Put in a new membrane, many new fittings and had to turn off a sensor that keeps telling me to replace the prefilters but then we got it working.


My memory is that it put our 6.5+ gal/h which was great. Low PPM and I was happy. We did a winter in the Bahamas and put the boat away for a year with pink antifreeze.


Now I've recommissioned it, in the process Iv'e had to turn off the airlock sensor. It runs but...


The output is LOW... 4.2-4.6 gal/h
The salinity is HIGH... fluctuates in the 500s


I fear the membrane might be damaged and I'm not sure how to test/rule that out.


The pressure reading on the panel ranges from 53 to 58psi.


The gauge on the accumulator tank reads zero so that's a concern. Either the gauge is broken or the tank has depressurized. When testing the gal/h at the tank I can see the pulsing that indicates perhaps the accumulator tank pressure is low.


I'm on anchor in the Bahamas with the family now but I can get to a town, pull that tank, find a bike pump and try to re-pressurize it. I'm not sure how the presence of pressure in the accumulator tank will effect output and quality but it can't hurt, right?


After that, I don't know what to do. The system is obviously a jalopy held together with string and bubble gum but I'd really like to get it working without sending off to the states for a box of (expensive) parts.



Any thoughts, ideas, insights would be hugely appreciated...

[GordMay]

Originally Posted by SVSeaHawk

I have a Spectra Ventura 150 ...
I repaired this and got it working with a lot of help from T.J. down in Florida (business name I can't remember)...

You might be thinking of JT [a very helpful CF member, “Tellie”*] at Halden Marine Service.

* Tellie ➥ https://www.cruisersforum.com/forums...llie-9014.html

Halden Marine Service, Dealers in Spectra, Watermakers, Florida Distributor for AMI watermakers, membranes and parts, Super Wind 350 generators, and SunWare Marine solar systems. Sales, service, installs.
➥ https://haldenmarineservice.com/

[SVSeaHawk]

YES! I think you are correct. He was super helpful getting this thing running.


I have already PM'd Tellie and all roads seem to be leading in his direction.

[Smokeys Kitchen]

I am in Mexico and have the same unit.

When my output dropped to mid to low 5’s gph and especially when salinity rose to mid to high 400’s I replaced the membrane as well as both prefilters and carbon block filter. Prior to running the unit under pressure, I manually flushed the new membrane for @ an hour with seawater. Just trying to make sure all the chemicals (storage) were off of it. I too, had to re-pressurize my accumulator tank and by-pass the pre-filter pressure sensors.

Current output is now in low to mid 6’s gph and salinity is @ 210 to 220.

I am certainly not Tellie but it sounds like the membrane is damaged and may need replacing. If so I would at least replace the carbon block filter also but probably put in new prefilters as well.

Just my thoughts - hopefully Tellie will weigh in.

Ron - S/V Just Lucky

[sailorboy1]

What I learned from my VT-150 is the number of things that go wrong it is HUGE. There are usage troubleshooting flow charts online if you search for them.

[SVSeaHawk]

Originally Posted by Smokeys Kitchen

I am in Mexico and have the same unit.

When my output dropped to mid to low 5’s gph and especially when salinity rose to mid to high 400’s I replaced the membrane as well as both prefilters and carbon block filter. Prior to running the unit under pressure, I manually flushed the new membrane for @ an hour with seawater. Just trying to make sure all the chemicals (storage) were off of it. I too, had to re-pressurize my accumulator tank and by-pass the pre-filter pressure sensors.

Current output is now in low to mid 6’s gph and salinity is @ 210 to 220.

I am certainly not Tellie but it sounds like the membrane is damaged and may need replacing. If so I would at least replace the carbon block filter also but probably put in new prefilters as well.

Just my thoughts - hopefully Tellie will weigh in.

Ron - S/V Just Lucky

Yeah, it's probably the membrane. The filters are new so that seems the likely culprit. Problem is I'm in Bahamas and getting one here is a whole thing.



Guess I was hoping for a way around that, a way to clean it, anoteher problem altogether.


BTW, what changes to your system did you see after pumping up the accumulator tank?

[carstenb]

Actually, my thoughts are that the feed pump is shot.

But you need to get your accumulator repressurized

JT from Halden is excellent and give you good advice on how to troubleshoot

[wrwakefield]

I’m with Carsten. I suspect feed pump pressure is low. Could be intake restriction [raw water intake, strainer, one or both pre-filters] or the in-feed pump is weak.

You definitely need to pressurize the accumulator tank [~65PSI if I recall correctly.]

I have shared the troubleshooting guide I use with our Spectra Santa Cruz [2 in-feed pumps; 12-14G/Hr] in case you don’t already have it.

Let us know how things turn out.

Cheers, Bill

[FlyingScot]

From the manual: The purpose of the feed line accumulator is to reduce the spikes in the feed pressure caused by the cycling of the Clark Pump. If the accumulator is not properly charged it can lead to problems with the Shurflo Pump pressure cutout switch. The accumulator has a Schrader air valve, like a car tire, which allows the internal air bladder of the accumulator to be precharged. The accumulator should be pumped up to about 65 psi (4.5 bar) for best results. Add air using a tire pump or air compressor. You can experiment with the exact pressure that will give the best pulsation dampening on your installation.

[SVSeaHawk]

Originally Posted by FlyingScot

From the manual: The purpose of the feed line accumulator is to reduce the spikes in the feed pressure caused by the cycling of the Clark Pump. If the accumulator is not properly charged it can lead to problems with the Shurflo Pump pressure cutout switch. The accumulator has a Schrader air valve, like a car tire, which allows the internal air bladder of the accumulator to be precharged. The accumulator should be pumped up to about 65 psi (4.5 bar) for best results. Add air using a tire pump or air compressor. You can experiment with the exact pressure that will give the best pulsation dampening on your installation.

Yes, saw this. Just not sure what problem those spikes in feed pressure might cause.


Also, the pressure cut out switch could be an issue in my case. I had a leak, since repaired, which corroded the leads to that pressure switch. I replaced the switch itself and believe it is working fine. But ofc nothing is certain.


In a general sense, I can understand how the pressure switch might get confused and shut off when there are pressure spikes. In that case I can see how the effective pressure of the pump would go down as the spiking pressure shuts it off momentarily.


If that were the case, the comments RE the pump being at fault would prove correct AND the membrane may not be damaged which is the outcome I am desperately seeking.


This is all very helpful...

[carstenb]

If you replaced the pressure switch - did you adjust it? It has an adjustment in the top. They are supposed to be set at 125 psi but you never know. Better yet - simply wire a bypass and don't use it. (we have run our spectra fro years with a bypass)

Check you pressure gauge. The clark pump should cycle at about 95-100 psi if I recall.

Unless you are sure the membrane is bad - the pump is a cheaper option to replace.

[SVSeaHawk]

Originally Posted by carstenb

If you replaced the pressure switch - did you adjust it? It has an adjustment in the top. They are supposed to be set at 125 psi but you never know. Better yet - simply wire a bypass and don't use it. (we have run our spectra fro years with a bypass)

Check you pressure gauge. The clark pump should cycle at about 95-100 psi if I recall.

Unless you are sure the membrane is bad - the pump is a cheaper option to replace.

Interesting...
I replace the actual switch inside the pressure switch assembly. ($10 Amazon)

Certainly could adjust the pressure. There is a screw on the pressure assembly, assume it's that. Will check manual.

Not sure how to determine the psi on that. How do I know when I've reached 125psi?


Of course, I could easily and will bypass the pressure switch on the pump and see if that makes a difference.That's a very good idea. I seem to be collecting bypass options left and right.



As for the clark pump PSI, the only reading i have are on the panel. They say the unit is running at 54-58psi. Spec seems to call for at least 55psi. Is this a different pressure reading?


Also, the pressure gauge on the accumulator tank reads zero even when the system is running. I would think it might bounce around as the clark pump operates, no? Wondering if this indicates a broken gauge.


Anyway, will test your idea this afternoon when I get into the next harbor.
Thank you, feeling optimistic...

[carstenb]

Originally Posted by SVSeaHawk

Interesting...
I replace the actual switch inside the pressure switch assembly. ($10 Amazon)

Certainly could adjust the pressure. There is a screw on the pressure assembly, assume it's that. Will check manual.

Not sure how to determine the psi on that. How do I know when I've reached 125psi?


Of course, I could easily and will bypass the pressure switch on the pump and see if that makes a difference.That's a very good idea. I seem to be collecting bypass options left and right.



As for the clark pump PSI, the only reading i have are on the panel. They say the unit is running at 54-58psi. Spec seems to call for at least 55psi. Is this a different pressure reading?


Also, the pressure gauge on the accumulator tank reads zero even when the system is running. I would think it might bounce around as the clark pump operates, no? Wondering if this indicates a broken gauge.


Anyway, will test your idea this afternoon when I get into the next harbor.
Thank you, feeling optimistic...

With the pressure switch still in line - put a kink in your hose from the feed pump to your pressure filter. If the pump won't generate enough pressure to kill the switch, you have a feed pump problem

[SVSeaHawk]

Originally Posted by carstenb

With the pressure switch still in line - put a kink in your hose from the feed pump to your pressure filter. If the pump won't generate enough pressure to kill the switch, you have a feed pump problem

OK, that's a good move too.
I jumped that switch. No change.
I will put it back and try as advised here.
Then I'll find a bike pump and work on the accumulator tank.


Do you think, should it turn out to be a pump problem that there are options to repair the pump itself in the field? O-rings. Seals. That sort of thing.

[senormechanico]

Have you checked for impeded flow to the pump?
The thruhull might have critters living in there.
Try disconnecting the input hose and see if you get a geyser.