July 26, 2010
All O.E.M. Manufacturers and Installers
HWH Corporation
Adjustment for all jack pressure switches
PRODUCT/SERVICE BULLETIN
If the jacks or an individual jack comes down but does not touch the ground, do not adjust the level sensor.
ADJUSTMENT FOR ALL JACK PRESSURE SWITCHES
Adjust the pressure switch(es) as described above.
Please contact HWH Corporation at (800) 321-3494 for technical advice or assistance.
MI95.44
08DEC15
ISSUE DATE:
FROM:
RE:
TO:
The 610, 625 and 725 systems utilize a pressure switch on each jack to achieve the proper stabilizing
pressure. Each jack should lift the coach 1/4" to 3/4" when stabilizing the coach. This will vary due to type
should be leveled in several different positions so that each jack can be checked. These pressure switches
There is an old style pressure switch and a new style pressure switch. The old style pressure switch has
has a rubber boot covering the adjustment body and the jam nut. The new switch does not have a rubber
boot, it has a sealing washer between the jam nut and the switch.
The adjustment for the two switches is the same except the rubber boot must be removed to access the
adjustment body. When removing a rubber boot, be careful to not pull too hard on the switch wire. The
wire connection to the switch could be damaged.
Before adjusting a switch, unplug the wire to prevent the wire from twisting. Remove the rubber boot if so
equipped. Loosen the jam nut and use pliers to turn the adjustment body. If a jack needs to lift a little
more for stabilizing, turn the adjustment body clockwise. This will increase the pressure. If a jack is lifting
too high, turn the adjustment body counterclockwise. This will decrease the pressure. Only turn the
adjustment body a half a turn at a time then check the operation of the system. Remember to plug the
switch in for the test. Repeat as necessary. When the adjustments are complete, snug the jam nut back
down. DO NOT OVER TIGHTEN. Hold the adjustment body with pliers to prevent the adjustment body
from turning while tightening the jam nut. Replace the rubber boot if so equipped.
SWITCH
BODY
LOCKING
NUT
PRESSURE
ADJUSTMENT
BODY
OLD STYLE
NEW STYLE
SEALING
WASHER
RUBBER
BOOT
(On I-80, Exit 267 South) 2096 Moscow Road, Moscow, Iowa 52760
(800)321-3494 or (563)724-3396
W
H
H
CORPORATION
R
Phone:
www.hwhcorp.com
(563)724-3408
Fax:
Internet:
are adjustable.
of suspension and chassis. There must be some lift to combat thermal contraction of the fluid. The coach
