IX System Piping
A. General System Piping Precautions
WARNING
INSTALL BOILER SO THAT THE GAS IGNITION SYSTEM COMPONENTS ARE PROTECTED FROM WATER (DRIPPING, SPRAYING, RAIN, ETC) DURING APPLIANCE OPERATION AND SERVICE (CIRCULATOR REPLACEMENT, ETC).
CAUTION
THE HEAT EXCHANGER USED IN THE BWC IS MADE FROM A SPECIAL ALUMINUM ALLOY. FAILURE TO TAKE THE FOLLOWING PRECAUTIONS COULD RESULT IN SEVERE BOILER DAMAGE.
•BEFORE CONNECTING BOILER, MAKE SURE THAT THE SYSTEM IS FREE OF SEDIMENT, FLUX AND ANY RESIDUAL BOILER WATER ADDITIVES. FLUSH THE SYSTEM IF NECESSARY TO ENSURE THAT THESE CONTAMINATES ARE REMOVED.
•DO NOT CONNECT THIS BOILER TO A SYSTEM THAT IS SUBJECT TO REGULAR ADDITIONS OF MAKEUP WATER OR ONE WHICH EMPLOYS RADIANT TUBING WITHOUT AN OXYGEN BARRIER.
•DO NOT ADD ANTIFREEZE OR OTHER BOILER WATER TREATMENT CHEMICALS EXCEPT THOSE LISTED IN PART XI OF THIS MANUAL.
•MAINTAIN THE PRESSURE IN THE BOILER AT A MINIMUM OF 12 PSI.
•DESIGN SYSTEM TO ENSURE THAT THE FLOW FALLS WITHIN THE LIMITS CALLED FOR IN TABLE 9.1.
B. System Design
Proper operation of the BWC boiler requires that the water flow through the boiler remain within the limits shown in Table 9.1 any time the burner is firing. Failure to maintain the flow within these limits could result in erratic operation or premature boiler failure.
There are two basic methods that can be used to pipe the BWC boiler. Method #1 is almost always preferred. The instructions on the following pages describe these methods for piping BWC boilers and explain how to size the circulator and piping. Additional information on hydronic system design may be found in Installation of Residential Hydronic Systems (Pub. #200) published by the Hydronics Institute in Berkeley Heights, NJ.
TABLE 9.1: FLOW REQUIREMENTS THROUGH BOILER
BOILER MODEL | MIN. REQUIRED FLOW | MAX. ALLOWABLE | |
(GPM) | FLOW (GPM) | ||
| |||
BWC070 | 4.0 | 9.0 | |
BWC090 | 4.0 | 9.0 | |
BWC120 | 4.5 | 12.0 | |
BWC151 | 6.0 | 15.0 |
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