Vulcan-Hart VSX24D, Service Manual

Page: 10 / 80

VSX SERIES STEAMERS - COMPONENT FUNCTION AND LOCATION
Page 10 of 80
COMPONENT FUNCTION AND LOCATION
CABINET BASE BOILER
CONTROLS
WARNING: THE STEAMER AND ITS PARTS ARE
HOT. USE CARE WHEN OPERATING, CLEANING
OR SERVICING THE STEAMER. THE COOKING
COMPARTMENTS CONTAIN LIVE STEAM. STAY
CLEAR WHEN OPENING EACH DOOR.
Water Level Gauge Assembly - permits visual
confirmation that water level is being maintained in
the boiler during operation. The correct water level
is a point one-half of the height of the glass. The
manual valves at the top and bottom of this
assembly must be fully open and only closed if the
glass tube is damaged.
Observe that the water is clean and clear in the
glass tube. The appearance of extreme murkiness
in the water indicates inadequate water quality and
will cause failure of controls and the steamer.
Warranty does not cover malfunction due to poor
water conditions. Blowdown and/or clean out the
boiler as outlined in “BOILER BLOWDOWN AND
STEAMER SHUT-OFF” under “STEAMER
OPERATION” and “BOILER” under “SERVICE
PROCEDURES”.
Water Level Control and Level Sensing Probes -
these controls allow water to enter the boiler to fill
and maintain the proper water level. They will also
shut off the heat source to the boiler if the water
level drops too low.
The water level control works by using three
different probe lengths to monitor the water level.
The probes consist of a high level (HL), low level
(LL) and low water cut-off (LLCO). The level sensing
probes may easily be removed to inspect for lime
build up. As a rule, the condition of these devices
will indicate the overall water condition of the boiler.
Clean the probes if needed.
NOTE: Controls may not function and serious
clogging will occur if a daily blowdown procedure is
not followed.
Boiler Fill Solenoid Valve - admits water to the
boiler when demanded by the water level control to
maintain the correct water level in the boiler.
Cold Water Condenser Solenoid Valve - allows
cold water flow into the boiler blowdown drain box to
condense steam and cool the hot water before its
discharge into the drain.
Cycling Pressure Switch - controls boiler pressure
between prescribed limits by turning the heat source
on and off.
High Limit Pressure Switch - a switch of identical
design to the cycling pressure switch but used as a
high limit. The pressure settings are at higher and
lower limits than the cycling pressure switch in order
to turn off the heat source before the boiler pressure
reaches its limit and automatically resets after the
pressure drops below the lower limit set point.
Blowdown/Drain Solenoid Valve - this valve is
plumbed into the drain pipe of the boiler. Newer
steamer models will automatically blowdown when
power is turned off by using a normally open
solenoid valve. Older models can have a solenoid
valve that is activated by depressing a separate
blowdown timer button or have a manual “ball” type
valve. Daily boiler blowdown is essential to proper
operation and component life by removing sediment
and scalants that may be lodged in the chamber of
the boiler.
Strainers - a strainer is used in the water inlet line
to prevent foreign matter from becoming lodged in
the fill or cold water condenser solenoid valves and
to keep unwanted particles out of the system. A "Y"
strainer should be inserted upstream of the fill
solenoid valve.
On models using a direct steam supply, a strainer is
used in the pressure regulating valve.
Power Switch - when turned ON, power is supplied
to the controls and the steam generating process is
started in the boiler. The power switch is located on
the front of the boiler control box.
Water Inlet Valve - the water inlet valve is used to
stop water flow to the steamer when the steamer is
being serviced. Newer models will have a small
Petcock type valve while older models will be a
“ball” type valve. This valve should remain open
during normal operation.
High Limit Thermostat - a protective device that
shuts off the heat source if the boiler temperature
exceeds a specified limit. All standard models are
equipped with a surface high limit.
Descaler - hangs submerged in water inside the
boiler and is used to help control boiler surface
scaling. Two descalers are used in each boiler.
Handhole Cover Assembly - when unbolted and
removed, allows internal examination and cleaning
of boiler shell and its components if required.