Direct Steam Models; Regenerated Steam (Older Models); Heater Contactors - Vulcan-Hart VL Series Service Manual

VL BOILER BASE SERIES CONVECTION STEAMERS - SERVICE PROCEDURES AND ADJUSTMENTS

DIRECT STEAM MODELS

CERTAIN PROCEDURES IN THIS
SECTION REQUIRES ELECTRICAL
TEST OR MEASUREMENTS WHILE
POWER IS APPLIED TO THE
MACHINE. EXERCISE EXTREME
CAUTION AT ALL TIMES. IF TEST
POINTS ARE NOT EASILY
ACCESSIBLE, DISCONNECT
POWER, ATTACH TEST
EQUIPMENT AND REAPPLY
POWER TO TEST.
These models consist of a pressure regulator and
gauge that run off a building's potable steam supply.
The regulator used will be of the adjustable type and
should be set for a discharge pressure of 10 psi. The
maximum input pressure to the regulator should be 15
psi. Incoming power (120VAC) for the compartment
controls is supplied from a junction box in the base.
REGENERATED STEAM (OLDER
MODELS)
CERTAIN PROCEDURES IN THIS
SECTION REQUIRES ELECTRICAL
TEST OR MEASUREMENTS WHILE
POWER IS APPLIED TO THE
MACHINE. EXERCISE EXTREME
CAUTION AT ALL TIMES. IF TEST
POINTS ARE NOT EASILY
ACCESSIBLE, DISCONNECT
POWER, ATTACH TEST
EQUIPMENT AND REAPPLY
POWER TO TEST.
The steam coils on a regenerated type steamer are
intended for use at a steam supply pressure of 15 psi
maximum. A pressure regulating valve is available as
optional equipment for steamers where a building's
steam supply pressure exceeds 15 psi. The regulator
used will be of the adjustable type and should be set
for a discharge pressure high enough for good steam
generation. This pressure can be monitored by the
supplied pressure gauge. The regulator should be set,
only when steam is flowing (steam solenoid valve is
open). If steam is heavy with condensate, install a ball
float trap in the steam line before the pressure
regulating valve.
F24650 Rev. A (1017)
SHUT OFF THE STEAM SUPPLY BEFORE
SERVICING THE UNIT.
To remove a steam coil, disconnect union in steam
supply line to the coils and in the condensate
discharge line from the coils. Remove header that
supplies steam to coils by disconnecting union at each
coil. In same way, remove coil condensate collection
header. Remove four bolts clamping each coil flange
in place and pull coil forward. Use a new flange gasket
when replacing coil. The faces that mate with gasket
must be clean.
Turn steamer power switch ON, allowing steam
generation and, consequently, pressure to rise to
normal operating level and then turn power switch
OFF for a final purging of boiler and steam supply
lines. Steamer is now ready for use.

HEATER CONTACTORS

The contactor can be serviced by removing the cover
of the contactor box.
A noisy contactor (hum or chatter) is generally due to
excessive dust or dirt on the armature pole faces or
around the armature core preventing the magnet coil
from pulling the armature into a completely sealed
position. This can usually be corrected by blowing or
wiping the pole faces clean. To inspect electrical
contacts, remove cover at top of contactor by
removing two screws which hold it in place. Replace
Page 38 of 93
CERTAIN PROCEDURES IN THIS
SECTION REQUIRES ELECTRICAL
TEST OR MEASUREMENTS WHILE
POWER IS APPLIED TO THE
MACHINE. EXERCISE EXTREME
CAUTION AT ALL TIMES. IF TEST
POINTS ARE NOT EASILY
ACCESSIBLE, DISCONNECT
POWER, ATTACH TEST
EQUIPMENT AND REAPPLY
POWER TO TEST.
DISCONNECT THE ELECTRICAL
POWER TO THE MACHINE AT THE
MAIN CIRCUIT BOX. PLACE A TAG
ON THE CIRCUIT BOX INDICATING
THE CIRCUIT IS BEING SERVICED.