Repair manual

DESCALE PROCEDURE FOR TWO & THREE PROBE GENERATOR BASE STEAMERS
STEP BY STEP PROCEDURE
IMPORTANT WARNING: BEFORE REMOVING THE HAND HOLE PLATE TO DESCALE ANY STEAM GENERATOR, MAKE SURE
THERE IS NO WATER OR PRESSURE BUILT UP IN THE GENERATOR. CHECK THE OUTER SURFACE OF THE GENERATOR TO
MAKE SURE IT IS COLD. TURN THE YELLOW HANDLE ON THE MANUAL FILL VALVE 90 DEGREES TO THE BODY TO
PREVENT ANY WATER FROM ENTERING THE UNIT. THIS LIQUID DESCALER IS DESIGNED TO BE USED WITH NO HEAT
APPLIED TO THE GENERATOR.
STEP #1
Before opening the hand hole plate in the generator make sure the red power switch is in
the off position. Open the electric circuit box in front of the generator and look for two
black square solid state timers mounted on the side. If there are two solid state timers
in the box, this unit has a TDS blowdown. The timer mounted on top is a one second timer.
1. IF THE UNIT HAS AN ASCO DRAIN SOLENOID VALVE, remove the white wire from the
terminal marked number 3 on the TDS timer to prevent the purge from coming on.
2. IF THE UNIT HAS A PARKER DRAIN SOLENOID VALVE, remove the red/white wire from
the terminal marked number 2 on the TDS timer and attach it to L2 on the
terminal block.
To open the hand hole plate, loosen and remove the nut and bar across the generator
opening. Place the end of a two by four on the hand hole plate. Rap the end of the wood
with a hammer in various places until the plate and gasket fall inside the generator.
Remove any scale build-up that can be taken out by hand or with a small vacuum cleaner. IF
THE GENERATOR HAS PREVIOUSLY BEEN REPLACED WITH A NICKEL PLATED ONE, DO NOT SCRAPE OR
SCRATCH THE SURFACE. Assess the scale build-up above the water level on the tubes and the
top to determine the number of descalings that will be needed.
Use 2 quarts of liquid cleaner regardless of the size of the boiler. If there is a heavy
build-up of scale (1/4" or more) on the upper tubes (above the water level) and across the
top of the generator, it will have to be descaled twice.
After removing the scale and determining the number of descalings needed, replace the hand
hole plate with the old gasket still on the plate.