Figure 5: Recommended Boiler Piping for Zoning with Valves
D. Install Drain Valve in return piping. See figure 5.
E.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 flushed. A qualified water treatment chemical specialist should be consulted for recommendations regarding appropriate chemical compounds and concentrations which are compatible with local environmental regulations.
F. After the boiler and system have been cleaned and
flushed, and before refilling the entire system add appropriate water treatment chemicals, if necessary, to bring the pH between 7 and 11.
G.Fill entire heating system with water and vent air from system. Use the following procedure on a Series Loop System equipped with zone valves. (See Figure 5).
1.Close isolation valve in boiler supply piping.
2.Isolate all circuits by closing zone valves or balancing valves.
3.Attach a hose to bib cock located just below
isolation valve in boiler supply piping. (Note - Terminate hose in five gallon bucket at a suitable floor drain or outdoor area).
4.Starting with one circuit, open zone valve.
5.Open bib cock.
6.Open fill valve
7.Allow water to overflow from bucket until dis charge from hose is bubble free for 30 seconds.
8.Open zone valve to the second zone to be purged, then close the first. Repeat this step until all zones have been purged, but always have one zone open. At completion, open all zone valves.
9.Close bib cock, continue filling the system until the pressure gauge reads 12 psi. Close fill valve. (Note - If
10.Open isolation valve in boiler supply piping.
11.Remove hose from bib cock.
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