DIR #2000527770 00
WATER
INLET
WATER
OUTLET
GAS
CONNECTION
PIPE
Heat exchanger
This appliance uses a finned copper tube heat exchanger
to maximize the heat transfer process. The heat exchanger
is mounted in the inner jacket on the front side of the
appliance. The heat exchanger is composed of two circular,
cast iron headers with 62 vertical finned copper tubes (FIG.
5-2) in two (2) concentric circles. A series of “V” shaped
baffles are installed between the individual tubes to control
the movement of the flue products over the finned copper
surface and increase heat transfer. Water enters the heat
exchanger and makes four passes over the area exposed to
direct heat from the burner. A circulating pump MUST be
installed to ensure proper water flow over the heat transfer
surfaces during burner operation. Water temperatures in
the heat exchanger are determined by water flow.
DIR #2000527769 00
Figure 5-2_Heat Exchanger
Initial set-up of maximum water flow
On initial start-up of the Power-fin, the maximum water flow to
the heat exchanger must be checked and manually limited with
a valve or bypass before normal operation begins.
Minimum water temperatures
A minimum return water temperature of 140°F (60°C) has
been established to control condensate formation based on
the Btu/hr output at rated burner input. Maintaining inlet
water temperatures to the appliance equal to or higher than
the specified minimum temperature ensures proper operation
of the appliance and prevents condensate formation on the
heat exchanger. An appliance allowed to sustain operation
at water temperatures lower than the specified minimum
temperature may not provide enough heat from the burner
to maintain water temperature in the heat exchanger above
the 140°F (60°C) dew point of flue products. Operation of the
appliance at a temperature below the specified minimum set
point will result in non-warrantable operational problems from
the condensate formation on the primary heat exchanger (see
the
Low Temperature Bypass Requirements
section on page 33
of this manual).
CAUTION
An appliance allowed to operate at return
temperatures below the specified minimum
setting may experience problems with
the operating controls, safety switches,
obstruction of the flue gas passages on the
heat exchanger, incomplete combustion and
possible flue gas spillage. Sustained operation
at lower than specified water temperatures
may cause hazardous conditions that may
result in personal injury or non-warrantable
damage to the appliance.
Inlet and outlet connections
For ease of service, install unions on the inlet and outlet
of the appliance. The connection to the appliance marked
“Water Inlet” on the rear jacket should be used for return
from the system. The connection on the header marked
“Hot Water Outlet” is to be connected to the supply
side of the system. Minimum water pipe connections to
this appliance is 4 inch (101.6mm) pipe. See the piping
requirements in the heating boiler section of this manual for
multiple appliance installations.
5
Water connections
25
Installation & Operation Manual
Figure 5-1_Water Connections
