Burnham IN3 Boiler User Manual


 
21
G. If a long term pressure test of the hydronic system is
required, the boiler should rst be isolated to avoid a
pressure loss due to the escape of air trapped in the
boiler.
To perform a long term pressure test including the
boiler, ALL trapped air must 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.