"Peggie Hall" wrote in message
. com...
RG wrote:

Peggie:

I've got a SeaLand Tankwatch 4 monitor system for my holding tank.
Lately, the sending unit for the 1/2 full reading has become
unreliable....

It's not any chemical buildup--you haven't used any chemicals. The
sender(s) are coated/clogged with the animal fats that are present in
waste. Detergent is the right cure, but it'll take a strong
detergent/water solution, not just a small bottle of it...and while it's
only the 1/2 sender that's malfunctioning now, the 3/4 and FULL are sure
to be next...so you'll need to fill the tank to do the whole job. I'd use
2 gallons in a 40 gal. tank. Take the boat out and do what it takes to
agitate the solution for an hour or more...then let the solution sit in
the tank for a few days. If anything short of removing the sending unit to
clean 'em manually is gonna work at all, that's the only that will. And it
may not.

So my suggestion: bite the bullet and do what it takes to gain access to
the tank one last time and replace the guage with this one:
http://www.ferriellosales.com/ The sender--unless your tank is
metal--goes on the outside of the tank, so it can never get clogged.

A little background on this company..it's new. Dennis Ferriello was the
national sales manager for Snake River Electronics for a number of
years...he and Snake River came to a parting of ways recently...Dennis
started his own competing company. He also took both the Snake River
engineers with him. Their website is a bit "woofy" (painfully obviously
homemade)...but don't be put off by that...he's put his $$ into designing
and making tank level monitors that are far superior to Snake River's
instead of paying for glitzy web design. And it's paying off...he's
already captured a major segment of the OEM market, and word of mouth is
already creating a growning market among boat owners. I've known Dennis
for about 10 years. He's always been committed to quality, and I'm glad to
recommend his products.



Thanks, Peggie. I'll try the detergent approach first, and see if I get
lucky. In the meantime, I've spoken to Dennis on the phone, and have
downloaded the instruction manuals on his products from his website. The
concern I have with his product is whether or not it is compatible with my
existing display and the wiring from the tank to the display. Sea Ray uses
its own display, wired to the Tankwatch sending units. From what I can
tell, Dennis' sender works on a variable voltage system, whereas the
Tankwatch system works on an on/off continuity system. My existing panel is
integrated into my electrical panel, and I'm not sure I've got room to mount
an additional readout panel elsewhere. And running new wiring from the tank
to the cabin of the boat is out of the question. But I'll study his
materials and go from there. If you have any comments on using Dennis'
sender with my existing wiring and readout panel, I'd be happy to hear them.
My existing readout panel recognizes four states of condition:

1. Empty: Just what you'd think

2. No readout (except for power on): More than empty, but less than 1/2
full.

3. 1/2 Full: More than 1/2 full, but less than full.

4. Full: Game over.

Thanks again,

Russ