Improved water pump w/Relay

[vineyardgray]

Found this blog post of great interest, l thought I'd share:
http://www.argonsailing.com/2016/02/water-water-everywhere-but-i-cant-flush.html?m=1

[Midnightsun]

Good mod on the "that" pump however replacing the unit with a better built unit is the answer. If they undersized the contacter and the failure rate is high, time to shop for a better built unit IMHO. Personally I keep a spare on board just in case as it we all know it will fail at the worst time possible. The article also mentions these pumps have an impeller which is not the case, they are diaphragm pumps.

I also have another failsafe which is to switch over to "river water" which uses the wash down pump to pressurise the water system using lake/river water. This was a mod I did a few years back which can be seen here. Long read but really a great modification assuming you boat in fresh clean water. viewtopic.php?f=13&t=3204&p=21171&hilit=river+water#p21171

[Viper]

Those micro switches tend to have a high AC amp rating but not much of a DC rating which is what our water pumps run on. It's important that the DC rating be sufficient as there is a huge difference in the way AC and DC act on contacts. I haven't had to replace a pump switch in some time so I don't recall their typical DC rating but I'll have to see if I can find one lying around that came out of a pump. Those micro switches are used in countless applications and the ones I've seen usually have a rating of 15A at 125/250 volts but only about half an amp at 125V DC. There is a vast selection of ratings out there but this spec is pretty common. The blog post mentioned they aren't rated for running motors but a lot of them are, they're used for that all the time and usually have a HP rating on them, but again that's usually for AC pumps not DC.

[km1125]

You could probably extend the life of those microswitches a lot by adding a capacitor across the contacts.

[bud37]

Good post ...seems to me like a good upgrade and work around to fix an engineering ( cost ) issue.

[Viper]

In my personal experience though, a freshwater pump failure has rarely been due to the pressure switch.

[Midnightsun]

Source of the post In my personal experience though, a freshwater pump failure has rarely been due to the pressure switch.

This was my point about getting another model/brand of pump as opposed to trying to fix a poorly engineered one.

[Viper]

Source of the post

Source of the post In my personal experience though, a freshwater pump failure has rarely been due to the pressure switch.

This was my point about getting another model/brand of pump as opposed to trying to fix a poorly engineered one.

I agree. I like the mod though, it's thinking out of the box. Those relays are great for countless applications. KM's suggestion of using a capacitor is also a good way to help reduce arcing.

[bud37]

Source of the post

Source of the post In my personal experience though, a freshwater pump failure has rarely been due to the pressure switch.

This was my point about getting another model/brand of pump as opposed to trying to fix a poorly engineered one.

I think that is a major problem nowadays, considering where all these parts come from in the first place. Just how can you figure out the quality of internal workings when many engineering decisions are made by bean counters and bonus plans.

I have tried over the last 10 years to buy North American made, it is very hard as some products appear ok on the surface but on inspection the parts come from all over, once again leaving them open to the cheap acquisition rule.

That faulty switch is the perfect example, for a few cents more it would probably be fine.

Darn shame IMO.

[Mikwallace]

Source of the post Found this blog post of great interest, l thought I'd share:
http://www.argonsailing.com/2016/02/water-water-everywhere-but-i-cant-flush.html?m=1

This might be a bit of an overkill? However, I did this setup in my RV and it’s made a significant improvement in my fresh water system. I already had the relay, ordered the Accumulator from Amazon, picked up a couple SS hoses from Lowe’s and 30 min later it’s working. Now the pump is quieter and it seems to operate smothrt