Watermaker Virgin

TQA · #1 01-07-2011

I bought my boat a year ago and it came with a Spectra Ventura 150 deluxe watermaker fitted.

Now I have never had a watermaker before so it was with some trepidation that I fired it up for the first time yesterday but I followed the instructions, ran it unpressurised to flush out the 'pickling' chemicals then closed the pressure relief valve and was gratified to see the product flow start after a few minutes and the water to taste sweet. The pressure was a little lower than the handbook suggested at about 65 psi but we are in warm Caribbean water so I was not concerned.

However after about a hour it has stopped making water and the pressure is now fluctuating between about 15 psi and 45 psi with a more pronounced pulse in the brine output.

The intake filter is clear.

What has gone wrong?

mitchbrown · #2 01-07-2011

TQ

There should be a Raw water strainer connected to the thru hull fitting and then a low pressure pump and then probably 2 filters which probably are 10 micron. if the pressure on the low side is to low it would have to be one of these 3 components causing the problem. there may also be an oil seperator filter in the mix and one of the filters may have a charcoal element in it. If the pressure gets to low the machine will usually shut itself off.

Mitch

Tel321 · #3 01-07-2011

A Spectra Deluxe 150 has no electronic controls. There are only two possible problems that would cause your watermaker to fail as you described. The most likely cause is that the feed pump head has failed. Not unusual for one that has sat for too long. The simple test for this is to run the watermaker with the pressure relief valved closed. While it is running pinch off the brine discharge hose. At the same time watch your pressure guage. On a good feed pump the pressures should quickly rise to around 125psi and the pump motor should shut off for a second then it will consistantly shut on and off. If this happens your feed pump is good. If the pressure will not rise to this limit and the feed pump continually runs with the brine discharge pinched off the feed pump has to be replaced. Though these pump heads are propriatary to Spectra it's an easy fix you can do yourself. If with the brine discharge pinched off the feed pump rises to 125psi but when you release the brine discharge the gauge falls back to reading 15-45 psi then the Clark pump needs to be re-built. Send it back to Spectra and they will refurbish the Clark pump and send it back. If it is the Clark pump don't hesitate to PM me for specific removal procedures of the Clark pump before proceeding.
Also the Clark pump has two strokes. The pressure guage when it goes up to 45psi and falls to 15psi is only one stroke showing what's going on on one side of the Clark pump. The very next rise to 45psi and fall to 14psi is the other side of the Clark pump. Both strokes should read the same 45psi-14psi.
Good Luck,Tellie.

TQA · #4 01-13-2011

Tellie

Thanks for the comprehensive reply.

My feed pump looks like it is OK as I get the 125 psi with the brine pipe pinched off so it is the Clark pump then.

As I am out in the Windward Leward island chain I have downloaded the field repair guide for the Clark pump and will give it a go myself.

southernyankee · #5 11-13-2012

Tellie,
I am in the process of buying a new boat and struggling with which water maker and the type of pump. The boat will have a genset of 5kw and hold 200 gallons of water. I have looked at the echotec and spectra. I would rather not run the echotec off the engine and would like to have the most redundancy possible. If I chose a AC model that can be run from an inverter, I have the engine alternator and genset as power sources in case one does not start. Any thougths on echotec vs. spectra?

Thanks!

Brian.

tellie · #6 11-13-2012

Tellie,
I am in the process of buying a new boat and struggling with which water maker and the type of pump. The boat will have a genset of 5kw and hold 200 gallons of water. I have looked at the echotec and spectra. I would rather not run the echotec off the engine and would like to have the most redundancy possible. If I chose a AC model that can be run from an inverter, I have the engine alternator and genset as power sources in case one does not start. Any thougths on echotec vs. spectra?

Thanks!

Brian.

Hi Brian,

It's been awhile since I've posted on SailNet. Choosing the right watermaker to fit your needs and your boats capabilities is not as simple as some would have you think. It takes a bit of thought and consideration and both asking the right questions and knowing the right questions to ask. First, I'm not a big fan of engine driven watermakers, especially on smaller diesel engines. It seems logical at first but you must be careful that adding a heavy high pressure pump does not affect your engines balance. Many manufacturers, especially Yanmar will void your warranty as soon as the see one of these bolted to their engines. There are some side loading issues with larger pumps as well. But in fairness there are those that swear by them, but not me. Tying your watermaking capabilities to a generator adds a second weak link. If your generator fails so does your AC driven watermaker. But these are popular with many and as long as there is plenty of AC from the generator they work fine. I'm a bigger proponent of DC watermakers because of their efficiency and they don't rely on a generator to operate but they will be fine with a generator running. If you are looking for redundancy in a watermaker then DC provides that with the generators capability as well. Also if redundancy is a prime objective then Spectras Cape Horn Extreme is an option to look at. It is the only watermaker on the market that has two feed pumps and if one fails the other will still make water and not require quick emergency repair, a nice feature to have when away from a supplier. Don't be easily fooled that bigger is always better. When sizing any watermaker many factors need to be taken into consideration and a good balance between use, needs, capacity, the type of cruising you intend to do, how many people on average are on board, and realizing your water usage will increase even if you are very water conscious, should be seriously discussed. If you'd like I'd be happy to expand upon this and help you get a better idea and a better comfort zone before you spend your money.

Best Regards
Tellie

Captainmeme · #7 11-13-2012

Tellie, Our boat is a 27 foot Nor'sea, inboard Yanmar. We have considered adding a water maker, and are leaning (well at least leaning until you said unbalance engine) to an engine driven system assuming there is space in the engine room for the pump. My reasoning for an engine driven maker is to add additional load to the engine while charging batteries.
I've read that just the alternator is not enough load for the Yanmar to keep it happy.

Can you expand upon unbalance some please. Are you saying the additional weight
cantilevered off the side of the engine is determinant? If so in what way? Or is it the
belt that drives the pump that puts an unbalanced force on the crankshaft pulley? Or some other force?
Seems to me that an engine driven watermaker would be more efficient since the conversion from mechanical energy to battery charge to DC motor torque is all
bypassed using the engine to drive the high pressure pump.

Jerry

Brent Swain · #8 11-13-2012

The side load of a pump is microscopic compared to the load of pistons banging down on a main bearing. Looks like Yanmar is just grasping for excuses to void your warrantee.
Electric drives are a huge source of watermaker failures. Nothing simpler than a V belt , and nothing simpler to repair. Keep it simple.
Pressure washer pumps with ceramic plungers, make great watermaker pumps, at around $300, and are much more solidly built than most watermaker pumps.

Captainmeme · #9 11-13-2012

Thanks Brent for the response. After asking about the engine driven pump I did some research and found an "app note" from Yanmar concerning this. What they recommend is
to keep the load within 30 degrees of horizontal, why I don't know. They also require the load be mounted to the same bed as the engine so both the engine and load move together.
That makes sense to me. If one was to mount the load to the hull and the engine was to
move around on the mounts I can see a slapping action transmitted via the belt.
Here is the link for those interested: ENGINE INSTALLATION

Another question, when or if the high pressure pump fails is it possible for the pump to leak oil into the membrane thereby contaminating it?

Geoff54 · #10 11-13-2012

Quote:

Originally Posted by Captainmeme

What they recommend is to keep the load within 30 degrees of horizontal, why I don't know.

The primary loading on the main bearings is in the same plane as the cylinders (well, not exactly but close enough). Presumably they don't want any increased loading in that same plane.