34
6A
Hydronic piping
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.
2. Boiler
circulating
pump:
Factory supplied. System piping must be sized to meet the
minimum requirements in Table 6A on page 35.
3. 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.
4. Check
valves:
Field supplied. Check valves are recommended for
installation as shown in FIG.’s 6-3 through 6-6. Failure
to install check valves could result in a reverse flow
condition during pump(s) off cycle.
5. Unions:
Field supplied. Recommended for unit serviceability.
6. 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.
7. Pressure relief valve:
Factory supplied. The pressure relief valve is sized to
ASME specifications. Install the 3/4" NPT fitting on the
top right side of the boiler (images in this manual show
relief valve installed).
8. Boiler
purge
valve:
Field supplied. The boiler purge valve is used to
remove entrapped air from the heat exchanger during
start-up.
9. System temperature sensor (optional):
Factory supplied with the unit. The manufacturer offers
a system temperature sensor (100157718). 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.
Installation & Service Manual
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.
10. 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.
F I R E T U B E C O M B I
™
