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DAKA Furnace Model 622
2008 Edition
Rev 2B: 11-9-12
VII. OPERATING CONTROLS
A. Fan Controls
The fan control on the side of the DAKA furnace has a rotating thermostat disc.
Holding the disc firmly in place, adjust the three tangs for these three settings from
left to right as follow:
FAN OFF - 90°, FAN ON - 130°, LIMIT - 200°.
These Fahrenheit settings will cause the 550-cfm back blowers on the DAKA furnace
to turn ON when the temperature within the air jacket rises to 130°, and OFF when
the temperature within falls below 90°. The limit setting will shut off the front 60-cfm
draft blower should an unsafe bonnet temperature over 200°F be reached. The
blower will be reactivated automatically when the temperature falls to 160°F.
While this fan control is designed for fully automatic operation, you can turn the back
blowers on manually at any time by pushing white button on fan control in. Pulling
button out will turn the blower off, unless the heat within the air jacket is above the
"FAN ON" setting of the dial, in which case the blowers will continue to run until the
temperature drops.
The snap-disc control inside the J-box ring is an operating control for the 60-cfm
draft blower, with a built in range of 190° OFF 170° ON, to prevent furnace
overheating. During normal operation this control may be activated frequently and is
designed to help level the furnace heat output.
IMPORTANT: In a supplementary "Add-On" installation, the blowers on the
DAKA furnace can be used as circulation blowers for heating the house.
They also can be used in conjunction with your primary furnace blower to
boost air circulation in large ductwork systems. An optional fan control may
need to be located in supply plenum to turn primary blower on and off when
heat is received from the DAKA furnace. (See FIG. 1 for fan control location).
B. Living Area Wall Thermostat Location
(22)
The Honeywell T812A1002D thermostat should be installed in any ground floor
room on an inside wall, preferably beside the thermostat governing the primary
furnace, which should be set approximately 5° lower than the DAKA thermostat.
When falling room temperatures call for heat, the DAKA thermostat turns on the 60-
cfm front draft blower on the DAKA furnace; the additional combustion air increases
the heat output until the DAKA room thermostat signals the blower to cut off.
Combustion air then reduces to a maintenance level with a relatively low heat
output, ready for the next firing cycle. Should there be insufficient fuel to increase
the room temperature as called for, the primary furnace will fire when the
temperature falls to the 5° lower setting. The DAKA draft blower will continue to run;
however, to turn it off, lower the DAKA room thermostat setting below that of the
primary furnace.