Conference unifix::sailing

>    Does anyone know why?   Am I note leaving the water pressure switch
>    on long enough?
    
You probably need to leave the water pressure switch on all the time. Most
of these systems have no pressure tank to save up water pressure for you.
The pump is designed to consume power only when you actually draw water. You
will typically hear the pump run whenever you draw water, and stop instantly
when you stop drawing water.

The hot water will deliver water for a while without running the pump since
the hot water tank will maintain pressure for a while because of the air
pocket at the top of the tank. (I'm not sure how much air is suposed to be
in there...?)

--RS

Yes, the water pump has a pressure switch to turn it off when the water
system pressure reaches 20 to 40 psi (or so). The circuit breaker for
the water pump should be left on. As .1 points out, many if not most
systems lack a water pressure storage tank (if that's the right term).
This means that the water pressure pump runs whenever a faucet is
opened. We found this annoying enough that I added a Jabsco water
pressure storage tank to our system. This tank allows 1/2 to 1 gallon of
water to be used before the pump turns on. 

Alan

    Is the water pressure switch and the water pressure circuit breaker
    one in the same (on the instrument panel).  If so, how long should
    it run before shuting off?

re .3:

No, the circuit breaker and pressure switch are separate. The pressure 
switch is normally part of the water presssure pump. When first using 
the water system the water pump may run for a few minutes until all the 
air in the system (eg, at the top of the hot water heater) is compressed. 
If the pump doesn't turn off, there may be a leak in the system or for 
some reason the pump isn't getting water from the main water tank. If 
you have two or more water tanks, there should be a separate shutoff 
valve for each tank between the tank and the water pump. 

Alan

(Our boat was delivered with a leaking tank fitting. Reaching the 
fitting required removing the water tank from the boat, which required 
major surgery to the joinerwork. Funny now, but not then.)

    The Valiant, I own, has 2 water tanks. Each has a shut off valve,
    both are currently on. Should this be the normal configuration ?
    Should I alturnate between usage ? One last thing, When I'm filling
    the tanks, where should I be looking to determine the tanks to be
    full ?
    

re .5:

A major reason for two tanks and two valves is to reduce the possibility
of running out of water. Another reason for two water tanks and two
shutoff valves is to reduce the chance of contaminated water in one tank
contaminating the water in the second tank. (It is an excellent idea not
to vent water tanks outside the hull to avoid the possibility of salt
water getting into the tanks.) Yet another reason is to prevent loss of 
all drinking water if one tank or the water system plumbing develops a
leak. This isn't much of a concern when coastal sailing, but could be
life threatening on an offshore passage. 

Our Valiant 32 has two 45 gallon water tanks. When filling the tanks we 
close both shutoff tanks and fill the tanks completely. Since the open 
ends of the vent hoses are above the level of the fill pipes, we know 
that the tanks are full when the water overflows from the fill pipe. We
then open only one shutoff valve (usually the valve for the port tank
since much heavy gear -- batteries, ground tackle, galley, etc -- is on
the port side) and use all of the water in that tank. When the tank is
empty, we know we have 45 gallons of water left. We then open the second
shutoff valve and allow the full tank to drain into the empty tank (we
don't normally worry about contamination). Now each tank contains about
22.5 gallons. One shutoff valve is then closed. This allows us know
about how much water we have and when we have to start conserving. When
cruising in cool weather a 45 gallon tank is usually enough for about
two weeks (crew of two) without undue care. 

    Alan,
    While you are on the subject..
    
    I installed a Par 2 faucet pump two years ago. Ended up ruining one
    house battery last year and severely limiting recharge of one the
    first year. The dang pump would try to cycle every so often. The
    pressure switch would say "I'm low", it would juice the pump motor
    but the motor would not want to full rotate. Draw lots of current.
    I could not find/detect any leaks in the system. The pump is
    the 89 buck model (lists for 130 or so) which is a separate motor
    that drives through a crank, as opposed to cheaper direct drive
    and more expensive belt drive.
    
    I have not replaced the sensor switch since they are not readily
    available. Oh yes, burnt out a motor last year because of it
    stalling.
    
    Any ideas??
    Don

re .7:

Hmmmm, sounds more likely that the motor is defective -- high current 
and inability to drive the pump might indicate some shorted windings. 
The pressure switch turns the pump on at a low pressure (say 15 to 20 
psi) and off at a high pressure (say 30 to 40 psi). If the pressure 
switch is turning off at too high a pressure, I would think that the 
pump would run at normal speed at low water pressure and then gradually 
slow down (and maybe eventually stop) as the pressure increases. 

The Jabsco diaphragm pumps seem to be reliable -- ours (a belt-driven 
model) has had no part failures in nine years, but a vent hole clogged 
and the pump wouldn't pump until the hole was cleaned. Our Jabsco 
diaphragm belt-driven bilge pump clogs much too easily, but it leaves 
very little water in the bilge so I tolerate the occasional disassembly 
and cleaning. My (not extensive) experience indicates that price and 
pump life are directly proportional. 

Your pump problems are a good argument for having a manual back-up pump.
Our manual pump has a Y-valve in the inlet line so that it can be used 
for either salt water or fresh.

    Being a liveaboard (in california this is possible) I generally
    use about 100 gal. of water a week; would use more but my wife goes
    ashore for her shower (for some reason she likes to let the water
    beat down on her). I agree with Alan that you should have a water
    pressure storage tank.  I have a 2 1/2 gal. tank which unlike the
    smaller ones has a rubber membraine that compresses for the pressure.
    
    I would suggest that you " T " a pressure guage into your system
    to determine the "off" pressure. 40 psi seems very high for a normal
    pump to obtain.  Probably 30 psi or less is normal.  With a motor
    going out it is almost impossible to guess if it was the switch
    or the motor without some idea of the cut-off pressure.

    Well, the motor burned eventually. I replaced it. same problem.
    Would start out fine, build up pressure, but never fully stop.
    I kept reducing the plumbing so there was just one outlet. no
    leaks, yet the pump strove every so often to start. /Starting
    current in DC (any motor) is always high. Even with a peaked battery
    you could watch the volt meter dip.
    
    I think it will just continue as a riddle. I separated the
    head from the system and bought a small Par in line (17 bucks
    at Boat U.S. which Im going to  plumb in this weekend. Whale
    makes a momentary switch you can bump with your knee to turn on
    but it is crummy. Has open contacts. I know this isn't serving
    .0s problem. Think of me as being a barnacle tagging along in the
    inlet to your prop shaft bearing.
    Don

re .9:

Your suggestion of a pressure gauge is a good one. According to the 
catalog I have, Jabsco diaphragm pumps shut off at 39 psi, which, as you 
mention, is higher than most. The higher pressure is nice when washing 
one's grubby self, but it does result in using more water.