Lochinvar Knight 80 - 285 - Manual (Page 31)

Installation & Operation Manual
31
6
Hydronic piping
(continued)
It is required that near boiler piping
systems utilize Primary/Secondary
configurations as shown in FIG.’s 6-4
thru 6-9 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 6A. 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 of piping,
4 - 90° elbows, and 2 - fully ported ball valves.
2. Boiler system circulating pump:
A Grundfos UPS26-99F pump will be provided by the
factory as the boiler circulation pump based on 20 feet
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. 6-3. 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 6-4 thru 6-9. 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.
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. Typically the sensor will be
located far enough downstream to sense system diluted
water temperature.
13. Indirect water heaters:
The Knight boiler may be piped to an indirect water heater
to heat domestic hot water with the space heat transfer
medium. As depicted in the piping diagrams on pages 32
thru 37, the space heating piping will branch off to flow
the space heat transfer medium through a single wall heat
exchanger coil inside the indirect water heater.
The Knight boiler is pre-configured to control the
operation of the DHW pump with Domestic Hot Water
Prioritization programming. The DHW programming is
designed to control and balance the space heating demand
with the domestic hot water demand.
Lochinvar offers the Squire which is a series of indirect
water heaters. The Squire features a stainless steel vessel
with a single wall stainless steel heat exchanger.
NOTICE
Pump sizing and flow requirements are
based on 20 feet of piping, 4 - 90°
elbows, and 2 - fully ported ball valves.
NOTICE
ƽ WARNING The National Standard Plumbing Code, the
National Plumbing Code of Canada and the
Uniform Plumbing Code limit the pressure
of the heat transfer fluid to less than the
minimum working pressure of the potable
water system up to 30 psi maximum. Also,
the heat transfer fluid must be water or other
non-toxic fluid having a toxicity of Class 1,
as listed in Clinical Toxicology of
Commercial Products, 5
th Edition.