7
Figure 4A: Boiler Piping for Circulator Zoned Heating System
Figure 3: Recommended Piping for Combination
Heating & Cooling (Refrigeration) Systems
To perform a long term pressure test including the
boiler, ALL trapped air must fi rst be removed from the
boiler.
A loss of pressure during such a test, with no visible
water leakage, is an indication that the boiler contained
trapped air.
L. Oil, grease, and other foreign materials which
accumulate in new hot water boilers and a new or
reworked system should be boiled out, and then
thoroughly fl ushed. A qualifi ed water treatment
chemical specialist should be consulted for
recommendations regarding appropriate chemical
compounds and concentrations which are compatible
with local environmental regulations.
M. After the boiler and system have been cleaned and
fl ushed, and before refi lling the entire system add
appropriate water treatment chemicals, if necessary, to
bring the pH between 7 and 11.