jeff_wisnia wrote:
fzbuilder wrote:

Hello all, I have a older 120v spa that overnight developed a short.
The spa is on a cement slab and if I stand on the cement barefooted, I
get a shock like tingling in the fingers. When I turn on the pump, it
gets a bit worse. I have a GFCI and tested it with a ground tester and
all good. I went one by one and unplugged the heater, the circ pump
and then finally the main pump. Still getting a small shock. Any help
would be appreciated.

The only thing I have done since yesterday is to add muriatic acid to
get my TA down. I added about a cup last night, ran the jets for a few
and covered it up.



This may sound far out, but have you considered the possibility that
there is current leaking through the cement slab from some source and
that's why you feel that tingle when you touch the grounded spa?

There have been quite a few dogs electrocuted here in Red Sox Nation in
recent years by leakage from defective buried cables making the pavement
quite electrically hot in certain spots and much less hot a foot away.
There were so many incidences of that a couple of years ago that the pet
supply places were selling lots of insulated doggie boots, and the
utility companies responsible for the buried cables were looking very bad.

Just a thought....maybe you should try using an ac milliampmeter to see
how much current will frow from your finger to a known good ground while
you are standing on that same spot on the cement?

Jeff


Somewhere I've read that dairy cattle can be stressed by the tingle they
get from stray currents in a concrete floor. The solution is to bond
all the rebar before you pour the concrete.

How about an aluminum pie pan weighted with sand? Wouldn't that be a
good pickup to spot check a concrete slab for voltage and current? I'd
wear dry rubber soles and not touch other things while touching the pan,
just in case more than a tingle is possible.