Troubleshooting Low Spectra WM Output

[witzgall]

Hi all;

Our new to us boat came with a nice Spectra watermaker, a simple 6gph unit. It was pickled with PP Glycol, for over 2 years. I know is says in the manual that this should be changed every year, but the Spectra guy I talked to at a boatshow said it should be ok.

Anyways, I flushed it and ran the unit for a total of 4 hours before re-pickling it. The pressure was around 50, and output hovered around 4gph. The manual says that with these symptoms, the feed pump is suspect. Before it take that apart, am I headed in the right direction? If so, any advice on servicing the feed pump?

Chris

[senormechanico]

Battery voltage will have a big impact on output.

Make sure it's getting rated voltage AT THE PUMP.

Could be you have weenie wiring, bad connections etc.

Ours puts out to spec even after ten years.

I don't bother with pickling, just refresh its own product water every six months.

It helps to be in the Pacific North WET with moderate temps.

The Spectra is below decks where it's always cool.

[witzgall]

Yeah, I thought about the voltage after I posted. Batt voltage was from 12.4 - 13+, depending on what the solar was putting out. This is not at the unit, so I will have to test that and check the wiring.

I don't think I could get away with not pickling here, stuff grows quickly here in NC.... The pump and membrane are in the lazarette and the rest is down below under the sink.

Chris

[Tellie]

Originally Posted by witzgall

Hi all;

Our new to us boat came with a nice Spectra watermaker, a simple 6gph unit. It was pickled with PP Glycol, for over 2 years. I know is says in the manual that this should be changed every year, but the Spectra guy I talked to at a boatshow said it should be ok.

Anyways, I flushed it and ran the unit for a total of 4 hours before re-pickling it. The pressure was around 50, and output hovered around 4gph. The manual says that with these symptoms, the feed pump is suspect. Before it take that apart, am I headed in the right direction? If so, any advice on servicing the feed pump?

Chris

What boat show,what guy? When you were walking away from the booth was your wife mumbling words like Adonis, Greek God or Fabio?

Senormecahnico is right. First start by checking the voltage at the feed pump terminals both with the watermaker running and also when it is not. The Ventura 150 or 180C units are voltage sensitive and need at least 12.3 volts to perform close to spec. Check all connections and clean as needed. Chick wire sizing against the wire chart in your manual. If all this checks out I'd start suspecting the feed pump head. It's not unusual for diaphragm pumps to dry out after sitting for long periods of time without use. A simple test is to run the system and while watching the pressure gage pinch off the brine discharge hose with a pair of pliers. A good feed pump will very quickly climb to around 125psi and shut off and on. A bad feed pump will not climb to 125psi and will continue to run at lower pressures without shutting on and off. These feed pumps are proprietary to Spectra. If the feed pump does pass this test then the culprit is the Clark pump. Again check the pressure gage when the system is running. The needle will rise and fall each time the Clark pump shifts. One rise and fall is one side of the Clark pump the next rise and fall is the other side. Note each high pressure mark and each low mark. Both strokes on the pressure gage should be the same. A very small difference is not a concern. If the differences are big then the Clark pump is not producing the right amount of pressure. My guess is that the problem is most likely a bad feed pump head. No big deal. Don't try to fix it, just replace it with a new one.

[senormechanico]

Thanks Tellie,

I value your opinion, especially when you're right, like THIS TIME !!
Seriously, Your posts are always read and agreed with by me.

Steve B.

Originally Posted by Tellie

What boat show,what guy? When you were walking away from the booth was your wife mumbling words like Adonis, Greek God or Fabio?

Senormecahnico is right. First start by checking the voltage at the feed pump terminals both with the watermaker running and also when it is not. The Ventura 150 or 180C units are voltage sensitive and need at least 12.3 volts to perform close to spec. Check all connections and clean as needed. Chick wire sizing against the wire chart in your manual. If all this checks out I'd start suspecting the feed pump head. It's not unusual for diaphragm pumps to dry out after sitting for long periods of time without use. A simple test is to run the system and while watching the pressure gage pinch off the brine discharge hose with a pair of pliers. A good feed pump will very quickly climb to around 125psi and shut off and on. A bad feed pump will not climb to 125psi and will continue to run at lower pressures without shutting on and off. These feed pumps are proprietary to Spectra. If the feed pump does pass this test then the culprit is the Clark pump. Again check the pressure gage when the system is running. The needle will rise and fall each time the Clark pump shifts. One rise and fall is one side of the Clark pump the next rise and fall is the other side. Note each high pressure mark and each low mark. Both strokes on the pressure gage should be the same. A very small difference is not a concern. If the differences are big then the Clark pump is not producing the right amount of pressure. My guess is that the problem is most likely a bad feed pump head. No big deal. Don't try to fix it, just replace it with a new one.

[Tellie]

Originally Posted by senormechanico

Thanks Tellie,

I value your opinion, especially when you're right, like THIS TIME !!
Seriously, Your posts are always read and agreed with by me.

Steve B.

Thanks Steve. The opinion is mutual.

J.T.