CleaverBrooks WB, Owner'S Operation And Maintenance Manual

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Pre-Start Preparation
3-2 750-136
Model WB Electric Boiler Manual
3.
There is a very high probability that, during shipment or storage prior to operation, the elements will accumu-
late moisture. The moisture will turn to steam when the elements are energized, rupturing the element casing.
To check for this condition, take a reading with an ohmmeter between one of the contactor terminals (load side)
to ground for each contactor. If the reading is less than 17,000 ohms for standard 3-phase connection, or
50,000 ohms for a single element, remove the fuses going to that contactor so that, during the first day’s opera-
tion, the low reading elements will not be energized, but will be heated by other dry elements and the moisture
driven out at a controlled rate.
There are alternate heating methods. Direct a heat lamp at the offending elements or remove the element assem-
bly, bake it in a 200º F oven for 8 hours, then reinstall and rewire. Following any of these procedures, the sup-
port element then may be put in operation by replacing the fuses after the elements have been rechecked with
an ohmmeter.
3.2 — Boiler and System Cleaning
One important phase in completing hot water heating installations and boiler startup is cleaning the system.
No matter how carefully a system is constructed, certain extraneous materials could find their way into the
boiler. Pipe dope, thread cutting oils, soldering flux, rust preventatives, soldering compounds, core sand, welding
slag, and dirt, sand or clays from the jobsite usually are found.
Cleaning a hot water system (either steel or copper piping) is neither difficult nor expensive. The three most com-
mon materials used for cleaning are:
a. Trisodium Phosphate (TSP)
b. Sodium Carbonate
c. Sodium Hydroxide (Lye)
Their preference is in the order shown. Prepare the cleaning solutions as follows, do not mix different types of
cleaners.
a. Trisodium Phosphate: one lb. for each fifty gallons in the system.
Moisture in the element may result in damage to the element.
Disconnect and lockout the main power to avoid the hazard of electrical shock, which could cause serious personal
injury or death.
! Caution
! Warning