Lochinvar 399 6Hydronic piping, Installation & Operation Manual, Near boiler piping components

Installation & Operation Manual

6Hydronic piping

NOTICE	Pump sizing and flow requirements are
	based on 20 feet (6 m) of piping, 4 - 90°
	elbows, and 2 - fully ported ball valves.
NOTICE	It is required that near boiler piping
	systems utilize Primary/Secondary

configurations as shown in FIG.’s 6-7 and 6-8 only. The use of other near boiler piping configurations could result in improper building and system flow rates leading to inadvertent boiler high limit shutdowns and poor system performance.

Near boiler piping components

1.Boiler system piping:

Boiler system piping MUST be sized per the pipe requirements listed in Table 6B. Reducing the pipe size can restrict the flow rate through the boiler, causing inadvertent high limit shutdowns and poor system performance. Flow rates are based on 20 feet (6 m) of piping, 4 - 90° elbows, and 2 - fully ported ball valves.

2.Boiler system circulating pump:

Field supplied. The boiler circulating pump should be based on 20 feet (6 m) of piping, 4 - 90° elbows, and 2 - fully ported ball valves.

3.Domestic hot water circulating pump:

Field supplied. The pump MUST be sized to meet the specified minimum flow requirements listed in FIG.’s 6-5 and 6-6. Consult the indirect water heater operating guide to determine flow characteristics for the selected product used.

4.Boiler isolation valves:

Field supplied. Full port ball valves are required. Failure to use full port ball valves could result in a restricted flow rate through the boiler.

5.Check valves:

Field supplied. Check valves are recommended for installation as shown in FIG.’s 6-7 and 6-8. Failure to install check valves could result in a reverse flow condition during pump(s) off cycle.

6.Domestic indirect hot water isolation valves:

Field supplied. Full port ball valves are required. Failure to use full port ball valves could result in a restricted flow rate through the boiler.

7.Anti-scald mixing valve:

Field supplied. An anti-scald mixing valve is recommended when storing domestic hot water above 115°F (46°C).

8.Unions:

Field supplied. Recommended for unit serviceability.

9.Temperature and pressure gauge:

Factory supplied. The temperature and pressure gauge is shipped loose. It is the responsibility of the contractor to install the temperature and pressure gauge on the boiler water outlet.

10.Pressure relief valve:

Factory supplied. The pressure relief valve is sized to ASME specifications.

11.Boiler purge valve:

Field supplied. The boiler purge valve is used to remove entrapped air from the heat exchanger during start-up.

12.System temperature sensor:

Lochinvar supplies a system temperature sensor. The sensor is to be installed in the heating loop downstream from the boiler hot water piping and

heating loop junction. The sensor should be located far enough downstream to sense system diluted water temperature.

13.Y-Strainer:

Field supplied. A Y-strainer or equivalent multipurpose strainer is recommended at the inlet of the heat exchanger to remove system particles from older hydronic systems and protect newer systems.

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