Crown Boiler MWC116ENL User Manual
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Expansion Tank (Included & Required)
4)
– This boiler is equipped with a built in expansion tank. This tank is suitable
for use on systems having a water content of up to 40.6 Gal. This tank is pressurized to approximately 14.7 psi.
On systems having water content in excess of 40.6 gallons, a second expansion tank must be provided. Locate
5)
this tank as close as possible to the return connection on the boiler.
As shipped, the expansion tank is suitable for installations where the vertical distance between the relief valve and
6)
the highest point in the system is 23ft or less. Consult the factory if it is desired to install this boiler on a system
having a greater height.
Fill Valve (Required)
7)
– Either a manual or automatic fi ll valve may be used. Connect the fi ll as shown in Figure 9.1.
Automatic Air Vent (Included & Required)
8)
– The boiler is equipped with an automatic air vent. Manual vents will
usually be required in other parts of the system to remove air during initial fi ll.
Low Water Protection
9)
– This boiler is equipped with a fl ow switch which will only allow the boiler to fi re when there
is fl ow through the boiler, and therefore water in the heat exchanger.
Isolation Valves (Optional - Not Shown)
10)
– Isolation valves are useful if the boiler must be drained, as they will
eliminate having to drain and refi ll the entire system.
Drain Valve (Required)
11)
– Install a 3/4” boiler drain (not supplied) in the return piping as shown in Figure 9.1.
Figure 9.1: Basic Piping
CAUTION
Failure to install the throttling valve or fl ow restrictor described on the boiler supply could result
in unreliable boiler operation