Watts AERCO KC Series User Manual page 9

Whether installing single or multiple units, install
the piping and accessories as shown in the
appropriate piping diagram located in the
Appendix G.. For applications other than
standard space heating, consult the AERCO
Boiler Application Guide, GF-1070, or AERCO
for the appropriate piping schematics.
The minimum flow rate through the unit is 25
GPM and the maximum flow rate is 150 GPM.
Each unit is fitted with 4" flanges for high flow
application and the system velocity at the unit
return should not exceed 5 feet per second.
Each unit must have individual valves on the
supply, and return, for maintenance. In multiple
unit installations, the flow through each unit must
be balanced.
Every boiler plant must have a source of make-
up water to it. As with any closed loop hydronic
system, air elimination and expansion
equipment must be provided as part of the
overall installation. All piping MUST include
ample provision for expansion.
2.3.3 PRESSURE RELIEF AND DRAIN
VALVE INSTALLATION
An ASME rated Relief Valve is supplied with
each unit. The supplied pressure relief valve
setpoint will be 30, 50, 75, 100, or 150 psig as
ordered from the factory. Install the pressure
relief valve in the tapping provided opposite the
system supply connection, (see figure 2.4). The
pressure relief valve should be piped in the
vertical position using the fittings supplied. A
suitable pipe compound should be used on the
threaded connections, and excess should be
wiped off to avoid getting any into the valve
body. The discharge from the relief valve should
be piped to within 12 inches of the floor to
prevent injury in the event of a discharge.
The relief piping must be full size without
reduction. No valves, restrictions, or other
blockages should be allowed in the discharge
line. In multiple unit installations the relief valve
discharge lines must not be manifolded,
(connected), together. Each must be individually
run to a suitable discharge location. The drain
valve provided should be installed on the right
hand side of the unit towards the bottom of the
shell. The valve should be pointed in the down
position, (see Fig. 2.4).
2.3.4 TEMPERATURE/PRESSURE
INDICATOR
The unit is supplied with one of two styles of
Temperature/Pressure Indicators that must be
installed in the tapping on the supply flange of
the unit (see Figs. 2.5a and 2.5b). A suitable
pipe compound should be used sparingly to the
threaded connection.
Figure 2.4
Relief and Drain Valve Location
Figure 2.5a
Pressure /Temperature Gauge Installation
4
INSTALLATION