VHX SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS
F24700 (October 2001)Page 29 of 68
D. Check ports in v alve body.
9. Reverse procedure t o i nstall.
BOILER BLOWDOWN/DRAINSOLENOID VALVE
The water contained in the boiler, bei ng under
pressure, should be "blown through" this valv e and
be noticeably visible ex hausting out the steamer
drain. Daily boiler blowdown is essential t o pr oper
operation and component life by r em oving sediment
and scalants that may be lodged in the chamber of
the boiler.
The boiler blowdown/drain process is an automatic
function and should start whenever the power switch
is turned OFF after a normal operating cycl e. The
blowdown solenoid is a normally open (N.O.) valve
that CLOSES when energized by the power switch.
When the power switch is turned OFF, the
blowdown solenoid is de-energized and the valv e
OPENS to allow the boiler to blowdown.
If the blowdown operation appears to function
sluggishly or not at all, considerabl e scalants may
be lodged in the drain line plum bi ng exiting the
boiler, strainer, and/or the blowdown v alve.
1. Turn the power switch OFF and al low boiler to
blowdown.
2. Turn the ON/O F F knob on the main gas valv e
to OFF.
3. Remov e t he strainer clean-out plug located in
the center of cap.
4. Turn the power switch ON and all ow the boiler
"fill water" to flush-out the drain line until no
debris is seen exiting the clean-out hol e.
5. Turn the power switch and the water supply
OFF.
6. Turn the ON/O F F knob on the main gas valv e
back to ON.
7. Remov e and c l ean the strainer as outlined
under "INLINE WATER STRAI NE R
CLEANING".
A. If the boiler blowdown is ok, then the drai n
line and valve are c l ear of debris and the
valve is funct ioning properly.
B. If considerable lime scal e debr is is
apparent, then not only the blowdown
valve, but also the boi ler and water level
probes must be thoroughly cleaned. See
"FILL AND COLD WATER SOLENO ID
VALVES" for an inspection and cleaning
procedure of a solenoid valv e and
"BOILER" for a procedure on boiler
inspection, clean-out and delim ing.
INLINE WATER STRAINERCLEANING
The procedure outlined below can be used to
inspect and clean the inline water strainer f or the
blowdown solenoid valve and, if installed, the inline
water strainer for the boiler fill solenoid valve. Inline
Y strainers should always be located upstream of a
water solenoid valve.
NOTE: For proper operation, the str ai ner must be
installed so the water flow is directed t owards the
solenoid valve and the l eg of the Y with a threaded
cap is pointing downwards to catch debris.
1. Turn the power switch OFF t o and allow the
boiler to blowdown.
2. When bl owdown compl etes, shut OFF the
water supply.
3. Remov e t he cap and strainer screen from the
leg of the Y pointing downwards toward the
floor.
4. Remov e t he screen from the cap and clean any
accumulated debris from t he scr een and al so
remove any debris trapped in the openi ng of
the strainer body.
NOTE: If screen can not be thoroughl y c l eaned,
replace it with a new one.
5. Insert screen into cap t hen r e- i nstall cap to
strainer body.
6. Turn the water supply and power switch ON
and allow the boiler to reach operating
pressure.
7. Turn the power switch OFF and c hec k strainer
for leaks, as the boiler blows down.