3 1 2 Essential Elements in a Space Heating System
. .
Backflow Preventer
Install a backflow preventer valve in the make up water supply to
-
the unit as required by local codes
.
Expansion Tank
An expansion tank must be installed in the space heating piping
to prevent excessive pressure from building in the system See the
.
examples of system application at the end of this section for the
installation location Refer to the expansion tank manufacturer s
.
’
instructions for additional details
.
Follow the guidelines below when installing an expansion tank
.
●
Connect an air separator to the expansion tank only if the air
separator is located on the suction side of the system circulator
.
●
VESTA VC boiler is equipped with an water connection and
differential pressure
.
,
feeding valve Therefore installation
of additional system water fill connection is not necessary in
most cases
.
●
If an additional water fill connection is required for a specific
use install the water fill connection at the same location as the
,
expansion tank s connection to the system
’
.
●
When replacing an expansion tank consult the expansion tank
,
manufacturer s literature for proper sizing
’
.
●
For diaphragm expansion tanks always install an automatic air
,
vent on the top side of the air separator to remove residual air
from the system
.
Isolation Valves and Unions
●
Full port ball valves are required for the boiler system Failure
.
to use full port ball valves could result in a restricted flow rate
through the boiler
.
●
Check valves are recommended for installation Failure to install
.
check valves could result in a reverse flow condition during
pump s off cycle
( )
.
●
Unions are recommended for unit serviceability
.
Pressure Relief Valve
To complete the space heating system installation you must install
,
a
3
/
4
,
in maximum 30 psi pressure relief valve to the pressure rerief
valve adapter located on the top side of the VC boiler An ASME
.
approved HV pressure relief valve for space heating system is
supplied with the boiler
.
WARNING
●
Installing the pressure relief valve improperly may result
in property damage personal injury or death Follow all
,
,
.
instructions and guidelines when installing the pressure
relief valve The valve should be installed only by a licensed
.
professional
.
●
The pressure relief valve must be installed vertically to the
pressure relief valve adapter on the top side of the boiler
,
as shown in the example below with the drain pipe outlet
,
exiting the side of the pressure relief valve horizontally and
elbowing down
.
CAUTION
Install the pressure relief valve as close to the boiler as possible
.
No other valve should be installed between the pressure relief
valve and boiler
.
Refer to the following illustration and install a pressure relief valve
to the pressure relief valve adapter located on the top corner of the
VC
.
boiler
Pressure Relief Valve
Return Pipe
Installing the System Piping 17