8
IMPORTANT: Circulators in the following illustrations are mounted on the system supply side, but
mounting on the system return side is also acceptable practice.
The boiler, when used in connection with a refrigeration
1.
system, must be installed so the chilled medium is
piped in parallel with the boiler with appropriate valves
to prevent the chilled medium from entering the boiler.
See Figure 5.
The boiler piping system of a hot water boiler
2.
connected to heating coils located in air handling
units where they may be exposed to refrigerated air
circulation must be equipped with fl ow control valves or
other automatic means to prevent gravity circulation of
the boiler water during the cooling cycle.
Hot water boilers installed above radiation level or
3.
as required by authority having jurisdiction must be
provided with a low water cut-off device.
When a boiler is connected to a heating system that
4.
utilizes multiple zoned circulators, each circulator must
be supplied with a fl ow control valve to prevent gravity
circulation.
Hot water boilers and system must be fi lled with water
5.
and maintained to a minimum pressure of 12 psi.
Bypass piping is an option which gives the ability to
6.
adjust the supply boiler water temperature to fi t the
system or the condition of the installation. This method
of piping, however, is not typically required for base-
board heating systems. Typical installations where
bypass piping is used are as follows:
This method is used to protect boilers from con-
A.
densation forming due to low temperature return
water. Generally noticed in large converted grav-
ity systems or other large water volume systems.
Figure 6 & 7.
These methods are used to protect systems using
B.
radiant panels and the material they are encased in
from high temperature supply water from the boiler
and protect the boiler from condensation.
NOTE#1: When using bypass piping, adjust
valves V1 & V2 until desired system temperature
is obtained.
NOTE#2: Bypass loop must be same size piping
as the supply and return piping.
CONNECTING SUPPLY AND RETURN PIPING
Figure 5 - Circulators Mounted on System Supply
