Product Water Divert Valve-???

[Windance III]

Hi,
we have a SeaRecovery watermaker Unit 600g/day on our Priveleg435. The Product water is fed directly into the tank. The only way to see or better hear if water is produced, is listening near the water tank. One can hear the water dripping into the tank. I would like to install a 3way valve to be able to test the prod. water before it goes into the tank.
Question: Must the valve be an "open before close" type i.e. that under no condition will the valve be closed and that the output of the membrane be blocked. Even for a split second, when switching over, is that critical?
Or will a standard 3 way brass valve do?
I appreciate the risk that the valve might be set in a middle position and could close the valve, but this is unlikely to happen.
Would appreciate your view,
thanks
Werner
Windance III

[GordMay]

A standard brass or plastic 3-way "Ball Valve" is all you require.
Should the valve be left in an "intermediate" (middle) position (somewhere between supply & divert), some water will be allowed to flow in each direction.
There will be no significant back pressure, and no "closed" position.

[Windance III]

Thanks Gord, appreciate your reply, am off the boat at present and will install it when we get back,
thanks and best wishes
Werner

[AnchorageGuy]

We have a Y-valve by Whale installed in the product line and a small discharge faucet with no turn off handle at the galley sink to test the product first.

[Hyprdrv]

What happens when the tank is full and back pressure occurs at that time??

Steve

[AnchorageGuy]

Never happened in 10 years. The discharge faucet is at the galley sink counter so it runs into the sink and it is much higher than the tank. My tanks are not under any pressure even when full at least not enough to force water out. Our tank is 100 gallons.

[Windance III]

My concern was back pressure to the membrane but does not seem to be problem under normal circumstances, surely the tank has an overflow, not that I have seen one,
rgds

[Hyprdrv]

I think I get it now, The tank isn't pressurized, the pressure pump to the house system is after the tank so it draws water down from the tank. The tank must have some kind of float switch to shut the watermaker off once it reaches it's "fill" point so the tank doesn't become pressurized. The tank may have an overflow line though.

Thanks,
Steve

[George Elliott]

Steve These guys are right a regular vlve with 3 or 4 positions will work, I used a valve that I labelled brine discharge, sample, tank and off. If I remember correctly the valve is a Tempo for fuel systems with 1/4" ports. I only use the off position when the system is pickled, when switching from 1 position to the other you may see a brief spike on the preasure guage, but if you do it quickly you won't even see that. If you hang it up for long it'll simply blow the hose for product water running to the valve, typically it's just chepo clear line. good luck george

[Windance III]

Thank you all for the info,
Werner
Windance III

[Nauticatarcher]

How about a TDS Controller, Hannah or HM Digital make good relatively cheap ones and a 3 way solenoid valve, I installed this on ours so now when you turn watermaker on alarm sounds until TDS gets below user set poin and then controller trips solenoid valve and puts water to tank, if watermaker fails and starts making saltwater it will trip solenoid and discharge overboard, almost idiot proof and from memory cost about $150AUD to do

[Lancerbye]

The Village Marine unit that was in my boat when I bought it is also of the automatic type. You can set the level of solids in parts per million that you wish and it automatically switches from overboard discharge to the tank when the probe measures 200ppm above that range for what ever reason discharges overboard. The system consists of a small conductivity probe, a controller and a threeway solenoid valve.