Disconnect pressure switch on pump for watermaker?

[deepthought]

We have a spectra watermaker and thought one of the pumps went bad but when I checked it with out the pressure switch on the bottom the pumps seem to work fine. Anyone know if its ok to run it with out the pressure switch in the watermaker setup?

We have 2 pumps.

Thanks

[SV THIRD DAY]

A diaphragm pump is a positive displacement pump, so running it without the pressure switch will over amp the motor and trip the pumps thermal overload if all of the pumps output is not allowed to flow. So it won't work. Need to replace the switch or risk damaging the pump motor.

[Tellie]

Rich, you know I love ya man. Normally this is good advice and certainly makes perfect sense. But in the real world this is not an issue at all. Because of the nature of how a Spectra watermaker works, bypassing the pressure switch and direct wiring this particular feed pump is not a problem. deepthought's system is either a 380C, Santa Cruz, or the latest version a Cape Horn Extreme. In my personal opinion either of these three units are the knock down, drag out, go around the world watermakers. In fact years ago, after working with Spectra for a few years, they told me to pick any watermaker I wanted to put on my boat and I instantly chose the Cape Horn Extreme. You can run these two feed pumps dry for days, over pressurize them and under pressurize them and they will still keep on going without ill effect or any damage to the system. The Clark pump that is used on these systems is designed to take three times the pressures normally created by the the feed pumps and can certainly take much more. It would almost be impossible for these two feed pump to do any damage ether to themselves or to the rest of the system if over pressurized. Now I assure you this is not going to be Spectras advice for obvious reasons, but I have worked on thousands of these units and have bypassed the pressure switch many, many, times with zero effect. As I have stated to many customers many times, there are Spectras rules and then there are J.T.'s rules. These feed pumps do have one weak link and it is not a Spectra design. These are the two hot leads to the pressure switch. They are (GASP, faint, and cause southern women the Vapors) spade fittings. They are subject to corrosion and oxidation and are known to be an issue. Sotake the two red wire leading from the pressure switch and temporarily splice them together and go forward. When the time comes to replace a worn out feed pump head (it will happen) it will come standard with a new pressure switch and you can re-wire it back.

[a64pilot]

Maybe put silicone grease on the connectors the second time?

[deepthought]

Thanks for the advice yes it is a 380c and I have bypassed the switch and it is working fine. I was bit desperate earlier because I had everything out so I checked couple other watermakers around the anchorage.. One I dont remember the name just told me he didnt have the pressure switch connected and never had. I also saw a Schenker watermaker onboard another boat which looks very similar to my setup just with alot more electronics but I noticed that both of the pumps on it (looked the same as what I have) also did not have the pressure switches connected at all. So I will assume it is safe to not need it.

[senormechanico]

I dunno, maybe we should have a long multipage "crimp vs solder vs just connect those spade connectors"...
<sarcasm>