Operating Instructions; Adjusting The Temperature On The Munchkin Display - Munchkin 399M Installing, Operating & Maintaining

4. Do not use this appliance if any part has been under water. Immediately call a qualified serv-
ice technician to inspect the appliance and to replace any part of the control system and any
gas control which has been under water.
5. The Munchkin Heater shall be installed so the gas ignition system components are protected
from water (dripping, spraying, rain, etc.) during appliance operation and service (circulator
replacement, condensate trap, control replacement, etc.)
C. OPERATING INSTRUCTIONS
1. STOP! Read the safety information in Part 6.
2. Set the thermostat to the lowest setting.
3. Turn off all electric power to the appliance.
4. This appliance is equipped with an ignition device which automatically lights the burner. Do
not try to light the burner by hand.
5. Remove front cover.
6. Turn gas shutoff valve clockwise to "off". The handle will be vertical, do not force it.
7. Wait five (5) minutes to clear out any gas. If you then smell gas, STOP! Follow Part 6, Section
B/Lighting Instructions in the safety information. If you don't smell gas, go to the next step.
8. Turn the gas shutoff valve counter clockwise to "on". The handle will be horizontal.
9. Replace the Front Cover.
10. Turn on all electric power to appliance.
11. Set the thermostat to the desired setting.
12. If the appliance will not operate, follow the instructions "To Turn Off Gas To Appliance"
Section E and call your service technician or gas supplier.
D. ADJUSTING THE TEMPERATURE ON THE MUNCHKIN DISPLAY:
1. Before you can change the temperature from the factory setting of 180 degrees. You must make
sure that none of the thermostats are calling for heat. The Munchkin controller will not memorize a
program setting while in a heating cycle. To adjust the temperature to the Munchkin simply press in
the S3/Program key for three seconds until you see a flashing (C) then an alternate value of (180).
This number is the factory set point of the unit, which is 180 degrees. To change the temperature,
simply push either the
ture while the S2/+
Munchkin can be set as low as 50 Degrees and as high 203 Degrees. These ranges are your maxi-
mum and minimum ranges of the Munchkin. In addition to changing the temperature you are also
allowed to change three more settings in this model (1. Munchkin differential – 2. Indirect setting
(Vision System Only) – 3. Celsius to Farenheit measurement. Simply press in the
to get to next value, the Munchkin differential setting will appear in the display ch and alternating
value of 30. This allows the installer to adjust the activation of the burner based on the differential
temperature setting of the Munchkin. The burner will not start until the outlet water temperature
reaches a temperature that is equal to the temperature setting for the Munchkin, minus the differ-
ential EX: The Munchkin is set to heat at 180° F degrees and the differential is set at 20° F. The burn-
er will not start until the outlet temperature of the system falls below 159° F degrees (180° – 20° F =
160° F). To adjust, press either
F. Press the S3/Program
of 119 (Vision Systems Only) To adjust, press either
The final adjustment in this mode is the Farenheit to Celcius measurement. Press the
key again and you will see t and alternating value of F. To change value press the
choose the correct measurement.
30
S1/– or S2/+ on the display. The
will increase the temperature of the Munchkin. The temperature of the
S1/– (Decrease Value) or
key again and you will see the Indirect Setting de and an alternative value
START-UP PROCEDURES
S1/– button will decrease the tempera-
S2/+ (Increase Value) Ranges 5° F to 30°
S1/– (Decrease Value) or
S3/Program key
S2/+ (Increase Value).
S3/Program
S1/– or S2/+ to