As I'm sure you all know we had an alarm from our water system on
Tuesday 8/7. At this time I believe that everything is restored to
normal, but I will monitor it fairly closely for a while. I want
to
thank everyone for being careful about their water usage while we were
trying to get things fixed, with a special thanks to Doug who helped out
while we were force to manually control well pump. He saved me
many trips
back & forth on Shire Rd.
The short version of events is that the well guys, B&W Pump, wound
up having to replace the well pump. As it turns out they replaced
our
3/4 HP pump with a 1 HP version. This caused it to overload the
well
pump circuit. They were able to work around it leaving the well
pump
manually controlled by the circuit breaker in the power panel. So
there
were a number of days where Doug & I would turn the well pump on
and off trying to build up the level in the tank. Eventually I was
able
to get an electrician, Mark Hammond, to come out and tweak the well
pump switch. That put us back on an operational footing. The
bad news
is that the new well pump (with installation) cost just about
$2,600. I
haven't seen the electrician bill yet but expect it be no more than
than couple hundred dollars.
I learned some stuff along the way so I thought I'd write some stuff
down so it isn't just my little secret...
Water
Tank
Our water storage tank is 14.5 feet square on the outside.For calculation purposes I
guessed
that the
interior dimensions are 13.5 feet square allowing for 6" thick walls.So the horizontal cross section of the tank is about 182 square
feet.
The tank contains 6 probes at the following distances from
the top:
Distance from top
Usable Gallons
Level Description
29”
8,315
Well pump
off
48”
6,151
Well pump on
65”
4,215
Alarm
92”
1,139
Booster
Pumps Enable
98”
456
Booster
Pumps Disable
102”
0
Ground
So this means that the maximum usable capacity of our water tank is
about 8,300 gallons. Once the level in the tank falls to about
6,000
gallons the well pump will turn on and fill it back up. If the
level in
the tank ever gets to 4,000 gallons, the alarm will sound. The
bottom 3
probes will prevent the booster pumps (that pump water out to our
houses) from running dry if the tank ever gets down to the last few
hundred gallons.
Our average water usage has been about 1,000 gallons per day. So
that
means we have about 3 or 4 days of water in the tank when the alarm
sounds.
Pumps
Our system has 3 pumps. The well pump is 70 feet down in the
well.
It's job is bring water up to go either into the storage tank or out to
the community. The other two pumps are booster pumps that push
water out
to the community. Several years back we had trouble with our
booster
pumps losing prime causing a loss of pressure int he community. It
turned out that the problem was that the well pump would
pull water from the aquifer so fast that it would bring down the aquifer
level. Once the water level got down to the well pump, the pump
would
start supplying a mixture of air & water. The air would get
into
the booster pumps and cause them to lose prime, cutting the supply to
the community. The solution was to add a ball valve near the well
head
to limit how fast the well pump would take water from the well.
This
avoided the problem of air in the lines.
In the process of replacing the well pump, we've had to recalibrate the
ball valve to avoid getting air in the line. At the present time
the
valve is set to allow the well pump to produce about 2.7 gallons per
minute. So to produce the 1,000 gallons we need each day the pump
will
run about 6 hours a day. Bear in mind that this is an average
usage.
Normally the pump would turn on when there are 6,000 gallons in the tank
and would run about 12 1/2 hours to fill the tank back to the 8,000
gallon level. But it would only do this every other day.