There are several types fittings and unions
used on hot tubs and spas.
below is a breif description of some of the
types and abbreviations used.
- PIPE FITTINGS
- BARB type fittings are used with flexible
tubing and clamps and glue. Barbs can
be
smooth or ribbed.
- FPT means female pipe thread
- HOSE ADAPTER, means the end of a vacuumn
hose will fit over this. used mainly
on pools.
- MPT mean male pipe thread.
- SLIP means pipe will glue inside of this
fitting.
- SPG or SPIGOT, means a slip fiitting will
glue over this and it is the same size as
pipe.
- SLIP (SPG) COMBINATION - Pipe will glue inside
this and fitting of larger size will glue
over it.
- UNION THREADS
- Most all union nut threads are buttress threads.
- However the pilot thread depth will vary
and effect compatibility. See picture below.
