WaterFurnace Envision NHAC026, Installation Manual

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10
ENVISION AIR COILS INSTALLATION MANUAL
Hydronic Models
The water heater and hydronic air handler must be located
indoors and not subject to freezing temperatures. The water
heater must be installed in accordance to local codes and
its own installation instructions. The piping between the
water heater and air handler should be kept to a minimum.
Piping should be sized to allow for water velocities of 2’-4’
per second. At average water velocities, air bubbles should
be carried along the piping to an air separator where they
can be discharged from the system. Water velocities greater
than 4’ per second could cause flow noise and should be
avoided. If water lines pass through an unconditioned space
they should be protected to prevent them from freezing.
Valves should be installed to allow system isolation. All
closed loop hydronic systems must be equipped with
an expansion tank to allow room for the heated liquid to
expand. A system is considered closed when a check valve
or backflow prevention valve is installed in the cold water
pipe upstream of the water heater.
Once piping is complete all air must be purged from the
water lines. There is a dole valve at the top of the hydronic
coil header that can be opened to purge air from the coil.
There is also a plug at the bottom of the hydronic coil
header for draining the coil.
Plug for coil drainage.
Dole valve for air purging
Typical Installation. See the Hydronic Application Guide for other applications
LOAD PUMP
Source IN
P/T Ports P/T Ports
Ball Valve
Dielectric
Unions
Dielectric
Unions
WaterFurnace
HYDRONIC UNIT
WaterFurnace
ENCASED HYDRONIC COIL
*NOTE: A 30 PSI pressure relief valve
(Part No: SRV30) should be used in
hydronic applications.
1-1/2˝
FPT
Expansion
Tank
Air
Vent
Pressure
Gauge
30 PSI
RELIEF VALVE
Air
Separator
TO
DSH
FROM
DSH
Back Flow Preventer /
Pressure Relief Valve
Source OUT
GEO
STORAGE
TANK
P/T Ports