Spectra watermaker questions

[SVSeaHawk]

Originally Posted by BlueH2Obound

If you DO decide the membrane is bad, you might want to replace it (and the housing) with a non-spectra housing and membrane.
One of the reasons we didn't purchase a water maker that had proprietary parts was that we wanted to be able to open source replacement parts without going through the original manufacturer. But then, in 18 months of running (we're full time cruisers), we've not had to replace any parts other than the 5 micro, the 20 micron, and the carbon (backflush) filters (not membranes).
The industry standard membranes and membrane housings are considerably less expensive than proprietary parts.

Next boat perhaps. It would be like building your own lithium bank. There's a lot to be said for knowing your systems inside and out.

[carstenb]

Originally Posted by SVSeaHawk

For those still following along at home, i replaced the pump head and saw an improvement... not huge but something.


Pressure rose from 49psi as a low before to 54psi as a low now. Salinity down to 400s. Output up to close to 5gph


However, while testing the pump head I got a low voltage reading and started messing around with the multimeter.


The house bank was at 12.5v but the meter read 11.6 at the bus bar that powered the watermaker.


There is another circuit (water pumps) in the area and it was a higher gauge wire, (10awg, 8 maybe) so I put the water maker on that circuit. There was an improvement.


Then I put on the generator. The house bank went up to 13.1v but the meter read 12.6 at the watermaker bus bar. This combo put out 5.6gph and low 400s so I knew I was onto something. The pump pressure went up to a high of 61psi.



With the generator still running and the batteries still at 13.1 I put the water maker back on its usual busbar. It dropped to 11.6 despite the (12awg) wires reading 13.1 before I connected the watermaker.


I don't know that much about voltage drop and how the circuits are supposed to function. Any thoughts would be welcome...



Now I'm thinking I will install a15amp breaker off that fatter circuit and call it a day. Unless there is something about the above that indicates another problem or avenue for improvement ( a guy can hope).


Anyway, thanks for reading this far. It's been fun one so far...

Your readings indicate a bad or corroded connection or a bad or corroded wire. You need to find this

You may be getting 13.1 V but no amperage. Your problem lies here

Your busbar has an issue. Remove clean and replace all your wiring at the busbar. See if that helps

[sailorboy1]

Originally Posted by SVSeaHawk

I don't know that much about voltage drop and how the circuits are supposed to function. Any thoughts would be welcome...

well you have a bad connection and/or too small wires for the length

You proved that voltage is the problem it seems. If the system used to put out more flow what was the voltage back then? It is an unspoken thing that the capacity they claim is at high voltage AT THE PUMP

[BlueH2Obound]

Originally Posted by SVSeaHawk

Next boat perhaps. It would be like building your own lithium bank. There's a lot to be said for knowing your systems inside and out.

I may not have been clear. We didn't build our water maker out of purchase parts, we purchased a brand new, modular system that is already designed, just needing the final assembly, mounting the pieces and parts where you have the space. Absolutely stellar design. Narry a problem since installation!

https://seawaterpro.com/products/110...41104560652448

We went with the 120vac model, but they sell 12v as well. No affiliation, just a happy customer!

[SVSeaHawk]

OK the mysteries continue...
I went and removed a sketchy bus bar and tightened up the connections and now the Feed Water PSI is in the 80s, sometimes as high as 90.


The PPM is a little over 500.


But the output is still 5GPH.


I bought 8 gauge wire I was going to run to the panel but with the pump putting out 90psi now I'm not sure I see the point. I will check the actual voltage at the unit tomorrow but I assumed the point of improving voltage was to increase the feed water PSI which seems to have happened.


I guess I'm wondering why the output didn't improve. Ideas?

[Smokeys Kitchen]

Originally Posted by SVSeaHawk

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?

Getting back late ....

Since I repressurized the accumulator tank during the replacement of the membrane along with all the other filters, it would be difficult to tell what the exact difference was from the repressurization. I just know that it is working ok now.

[carstenb]

Originally Posted by SVSeaHawk

OK the mysteries continue...
I went and removed a sketchy bus bar and tightened up the connections and now the Feed Water PSI is in the 80s, sometimes as high as 90.


The PPM is a little over 500.


But the output is still 5GPH.


I bought 8 gauge wire I was going to run to the panel but with the pump putting out 90psi now I'm not sure I see the point. I will check the actual voltage at the unit tomorrow but I assumed the point of improving voltage was to increase the feed water PSI which seems to have happened.


I guess I'm wondering why the output didn't improve. Ideas?

Ok - the feed pressure is still on the low side. At what pressure does the clark pump cycle? You can hear it cycle from one side to the other - you can also see the sudden pressure drop on the feed pressure gauge.

Ours cycles at around 100psi. If your is cycling at 80-90 it is too low.

I forget - have you replaced the feed pump? If not, this may still be the culprit. Silly question - but are you sure your pressure filter is clean?

If you are really electrically minded you can take the motor apart and check to see if the brushes are worn to the nub - messy job, but doable

[SVSeaHawk]

Originally Posted by carstenb

Ok - the feed pressure is still on the low side. At what pressure does the clark pump cycle? You can hear it cycle from one side to the other - you can also see the sudden pressure drop on the feed pressure gauge.

Ours cycles at around 100psi. If your is cycling at 80-90 it is too low.

I forget - have you replaced the feed pump? If not, this may still be the culprit. Silly question - but are you sure your pressure filter is clean?

If you are really electrically minded you can take the motor apart and check to see if the brushes are worn to the nub - messy job, but doable

Are you sure about that PSI number. I thought I was shooting for 55-70PSI in the feed water.


The brushes are an interesting thought. Are they replaceable? I'll go look through the parts list...

[SVSeaHawk]

OK - I rewired the circuit from the panel to the watermaker with 8 gauge wire. Tested it before the rewire and the unit was running at 10.8volts off 12.45V at the panel. With the new wiring It was 12.3v with 12.45 at the panel. An improvement...


HOWEVER the output and PPM has remained the same.


56-61psi and ~500ppm with 5.6gph


I replaced the 20 an 5 micron filters while I was in there.



yesterday there was a strange 90psi reading at the panel. Still the same output and ppm.



I am running out of ideas here.



carstenb suggested I look at the brushes on the motor (thanks for the idea) however I think the psi is within spec and loath to open that can of worms.


That leaves me with... a membrane issue?


Would replacing the membrane increase output?



As a round up, I've...
replace the pump head.
Pressurized the accumulator tank to 60psi.
Replaced the 5 + 20 micron filters.
Checked for leaks, bled it for air.
Tightened the valve with a (gentle) wrench.
Checked the flow into the system at the thru hull.
Rewired the circuit with 8 gauge wire.



Ideas? Anyone?

[Bellinghamster]

Feed pump pressure depends on the model. From the troubleshooting guide:
The pressures shown on the Spectra gauges and panels are the feed pressure not the membrane pressure. Because each model as a different feed pressure ratio, each model will have a different Nominal operating pressure. And, because sea temperatures vary widely and Spectra Watermaker membrane pressures vary with sea temperature, each model has a Nominal Operating Pressure Range, but System Flow should vary only slightly.

Model Press Relief Closed Press Relief Open Feed Flow
VENTURA 150 55-70 PSI 20-30 1.5GPM
200C 7 0-80 PSI 20-30 1.5GPM
CATALINA 300 90-110 PSI 20-30 2.3GPM
380C 90-110 PSI 20-30 2.7GPM
NEWPORT 400 100-115 PSI 20-30 2.8GPM
NEWPORT 700 150-170 PSI 30-40 3.8GPM (15% Clark Pump)
NEWPORT 700 190-210 PSI 50-60 2.6GPM (20% Clark Pump)
NEWPORT 1000 190-210 PSI 50-60 3.5GPM
Normal pressures may fall outside of these nominal pressures in extreme arctic or tropical
inland sea conditions.

[sailorboy1]

Originally Posted by SVSeaHawk

Ideas? Anyone?

Have you looked at the troubleshooting flow chart? Because you keep asking about things that are in it.

Have you done a flow measurement? If your feed pump puts out rated flow at the correct pressure what does the chart say your problem is?

[SVSeaHawk]

OK - looked at that again. The chart seems to say all i can expect is 5.8gph. Flow chart says...



"Model 150 Product 5.8gph"







I'm surprised. I thought I was looking for 6.5pgh. Internet says...



"The Ventura 150 operates anywhere in the world and delivers over 6 gallons (24 liters) an hour"


Also the ppm is 500-ish. Not ideal but live-with-able if the output were higher.

[sailorboy1]

In the 2 years I had a VT 150 it NEVER did 6-gph. Something in the low to mid 5s was the norm

I rewired the circuit from the panel to the watermaker with 8 gauge wire. Tested it before the rewire and the unit was running at 10.8volts off 12.45V at the panel. With the new wiring It was 12.3v with 12.45 at the panel. An improvement... 12.3 V is pump while it is operating


HOWEVER the output and PPM has remained the same. The ppm has nothing to do with the flow, it is just is about the membrane and/or leaks


56-61psi and ~500ppm with 5.6gph well that is pretty good really, I would stop tryin g to "fix" it

[carstenb]

Interesting

our spectra 200T has clark shifting pressure of 95-105 which is within the norm. It produces about 7.5 gallons per hour (not the >8 spectra claims) ppm around 150-160

we've had the unit for close to 8 years and it has made all our water so probably something like 15,000 liters or more.

we've replaced the feed pump 3 times and the membrane once

Rebuilt the clark pump although it turned out it didn't need it

[Tupaia]

Originally Posted by SVSeaHawk

OK - looked at that again. The chart seems to say all i can expect is 5.8gph. Flow chart says...



"Model 150 Product 5.8gph"







I'm surprised. I thought I was looking for 6.5pgh. Internet says...



"The Ventura 150 operates anywhere in the world and delivers over 6 gallons (24 liters) an hour"


Also the ppm is 500-ish. Not ideal but live-with-able if the output were higher.

The 150 in Ventura 150 stands for US Gals per day (24 hours) that equates to 6.25 US Gals per hour MAXIMUM. The acceptable PPM in the manual is 750. PPM takes several mins to go down after start up.

I have had my unit from new 21 years and have only ever achieved between 5.3 and 5.8 US Gals/hour (130-140G/D) PPM is around 200-220 at 65-70 PSI. Current membrane was replaced when the Clark pump was rebuilt under warranty because of some cracks in the housing after 11 years. My first membrane ran at 70-75 PSI but still only produced 5.3-5.8 USG/hour. My unit has a Z-brane so has never been pickled and is still using the original feed pump but numerous pressure switches.


Causes of higher than expected PPM

If the membrane has been pickled expect the PPM to go up. There is a cleaning procedure given in the manual.

Chlorinated flush water with an out of date charcoal filter.

The membranes will also fail or produce high PPM if they are allowed to dry out.


Performance issues can also result from use of "paper" pleated pre filters.