Vulcan-Hart MHB24G Electric Steamer User Manual


 
VHX SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS
F24700 (October 2001)Page 23 of 68
SERVICE PROCEDURES AND ADJUSTMENTS
WARNING:
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.
BOILER
Inspection
It is recommended the boiler be inspected for
excessive lime scale build up in a time frame
dependant on the quality of the local water supply
and steamer usage. In hard water areas or for
steamers heavily used, a frequent interval should be
used. This inspection consists of an internal
examination and cleaning of the boiler, an
examination of the two hanging descalers, and for
lime build up on the water level probes. Also, a
check of all boiler controls, including the pressure
switches.
Periodic service must be performed as outlined in
these procedures. See WATER CONDITIONING
under GENERAL.
Clean-Out
1. Turn power switch OFF.
A. Boiler should automatically start
blowdown/drain cycle.
2. Remove the burner assembly and heat
exchanger as outlined under "HEAT
EXCHANGER" in "REMOVAL AND
REPLACEMENT OF PARTS".
NOTE:
Access to the interior of the boiler through
the hand hole cover is very limited on this model
and is recommended to be removed for deliming
purposes only.
3. Remove old descalers (cathodic protectors).
4. With a wire brush or equivalent:
A. Dislodge and remove all loose scale from
boiler shell. The loose material must be
scooped from the boiler or flushed through
the washout drain.
B. Remove all loose scale form the heat
exchanger.
C. Clean the mating surfaces of the heat
exchanger and boiler.
5. Check probe housing and water level probes
for scale build up and clean as necessary.
Refer to "WATER LEVEL CONTROLS TEST".
6. Check the drain line exiting the boiler for
obstructions.
A. Remove the strainer clean out plug, turn
the steamer on and allow the boiler "fill
water" to flush-out the drain line. Turn the
steamer off, remove the cap and strainer
screen and clean, if necessary, before
replacing the screen and clean-out plug.
7. Inspect condition of the descalers as outlined
under "DESCALER (Cathodic Protector)" in this
section, and replace if necessary.
8. Install a new gasket and replace the burner
assembly and heat exchanger by reversing the
removal procedure from step 2.
9. Delime the boiler as outlined under
"DELIMING" in this section.
Deliming
Boiler deliming should be performed in a time frame
dependant on the quality of the local water supply
and steamer usage. In hard water areas or for
steamers heavily used, a frequent interval should be
used. See WATER CONDITIONING under
GENERAL.
On steamers using a water treatment system, follow
the instructions for that system to delime the boiler.
Only use the type of chemical recommended or
described in the instructions for deliming with this
type of system.
If a water treatment system is not
used, follow the
instructions for deliming the boiler as outlined in the
steps below.
1. Turn power switch OFF.
A. Boiler should automatically start
blowdown/drain cycle.
2. Remove hand hole plate and gasket (top front)
from the boiler by removing the nut and clamp,
then tap the cover lightly to free it. Hold the
stud in the plate while tapping to prevent the
plate from dropping into boiler.
3. Clean the mating surfaces of the hand hole
opening and plate.
4. Delime the boiler:
A. If the boiler was delimed through a water
treatment system, proceed to step 7.
B. If the boiler has not
been delimed,
proceed to step 5.