12
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
ASTON SERIES AIR HANDLER INSTALLATION MANUAL
LOAD PUMP
Source OUT
P/T Ports
P/T Ports
Ball Valve
Dielectric
Unions
Dielectric
Unions
G Series
HYDRONIC UNIT
G Series
HYDRONIC AIR HANDLER
*NOTE: A 30 PSI pressure relief valve
(Part No: SRV30) should be used in
hydronic applications.
Ý
FPT
Expansion
Tank
Air
Vent
Pressure
Gauge
30 PSI
RELIEF VALVE
Air
Separator
TO
DSH
FROM
DSH
Back Flow Preventer /
Pressure Relief Valve
Source IN
GEO
STORAGE
TANK
P/T Ports
