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To perform a long term pressure test including the boiler, ALL trapped air must first 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.
K.Oxygen Corrosion:
Oxygen contamination of the boiler water will cause corrosion of the iron and steel boiler components, which can lead to failure. As such, any system must be designed to prevent oxygen absorption in the first place or prevent it from reaching the boiler. Problems caused by oxygen contamination of boiler water are not covered by Burnham's standard warranty.
There are many possible causes of oxygen contamination such as:
1.Addition of excessive
2.Absorption through open tanks and fittings.
3.Oxygen permeable materials in the distribution system.
In order to insure long product life, oxygen sources should be eliminated. This can be accomplished by taking the following measures:
1.Repairing system leaks to eliminate the need for addition of
2.Eliminating open tanks from the system.
3.Eliminating and/or repairing fittings which allow oxygen absorption.
4.Use of
5.Isolating the boiler from the system water by installing a heat exchanger.
10.INSTALL DRAFT HOOD without modification on outlet of flue collector (See Figure 1). Secure with sheet metal screws.
WARNING
Do not alter boiler draft hood or place any obstruction or
11.Install blocked vent switch
The blocked vent switch assembly shipped taped to the top of the boiler includes a power cord and a switch attached to a mounting bracket. The mounting bracket has a three tooth staggered comb stamping at one end with a #10 sheet metal screw in the center tooth.
A.Untape the blocked vent switch assembly from the top of the boiler and uncoil the power cord.
Figure 6
B.Pinch the black strain relief bushing installed in the jacket right side panel to dislodge it from the jacket and pull just enough of the black power cord out so the blocked vent switch will reach the near side of the draft hood skirt. Do not pull out more power cord than necessary.
C.Position the mounting bracket (with switch attached) onto the lower edge of the draft hood skirt by locating the center tooth (with the #10 sheet metal screw) on the outside and the other two teeth inside the draft hood skirt. See Figure 6.
D.Slide the mounting bracket up tight against the lower edge of the draft hood skirt, so that the #10 sheet metal screw is above the skirt's stiffening rib.
E.Secure the bracket in this position by tightening the #10 sheet metal screw against the outer surface of the draft hood skirt.
F.Reinsert the excess power cord through the jacket side panel hole to take the slack out of the power cord running up to the blocked vent switch.
G.Reposition the strain relief bushing around the power cord at the jacket side panel, pinch the two halves of the bushing together, and snap it back into the hole in the jacket side panel to secure the power cord to the jacket.
H.Be sure the power cord, mounting bracket, and switch are secure and located as shown in Figure 6.