8
During heating cooling cycle open valves
3.
C and D, close
valves A and B.
Maintain a minimum clearance of one (1") inch to
A.
hot water pipes. In air handling units where they
may be exposed to refrigerated air circulation, the
boiler piping system MUST be supplied with flow
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 must
4.
be provided with a low water device either as part of
the boiler or at the time of boiler installation.
When a boiler is connected to a heating system that
5.
utilizes multiple zoned circulators, each circulator must
be supplied with a flow control valve to prevent gravity
circulation.
* Reduced pressure back flow preventer must be
present under provisions required by the Environmental
Protection Agency, (EPA).
Bypass piping is an option which gives the ability to
6.
adjust the supply boiler water temperature to fit the
system or condition of the installation. Although, this
method of piping is not typically required for baseboard
heating systems.
This method is used to protect systems using
A.
radiant panels and the material they are encased
in from high temperature supply water from the
boiler. See figure 6 above.
CONNECTING SUPPLy AND RETURN PIPING
This method is used to protect boilers from
B.
condensate forming due to low temperature return
water. Generally noticed in large converted gravity
systems or other large water volume systems. See
Figure #7.
This method is used to protect boilers from
C.
condensate forming as well as protecting the
heating system from high water temperature. See
Figure #8.
Note:
7.
When using bypass piping, adjust valves A and
B until desired system temperature is obtained.
Bypass loop piping must be the same size piping for the
8.
supply and return.
Typical installation using circulators is shown in
9.
Figure
#9.
Typical installation using zone valves is shown in
10.
Figure #10.
See
11.
Figure #11 for typical piping for domestic hot
water heater.
For further piping information refer to the I=B=R
12.
installation and piping guide.
Figure #7
