LAARS Heating Systems
Page 30
The Mascot ST has been set up at the factory for
altitudes of less than 2,000 ft, but it may be installed at
elevations up to 10,000 ft for use with Natural Gas or
Propane. If the installation is at an altitude of greater than
2,000 ft, then altitude settings need to be adjusted in the
Installer Mode as describe below.
NOTE: Above 2,000 ft (610 m), the water heater will
de-rate by 2-4% for each 1,000 ft (305 m) of altitude gain.
The Mascot ST cannot be converted from Natural Gas to Propane (or vise-versa) in the field by non-certified
technicians. Contact the Factory or your manufacturer’s representative.
9:HA
Choose the correct value from the
following four options.
0 - 2
0 ~ 1,999 ft (0
-
609 m)
2
-
5
2,000 ~ 4,999 ft (610
-
1,523 m)
5
-
8
5,000 ~ 7,999 ft (1,524
-
2,438 m)
8
-
10
8,000 ~ 10,000 ft (2,439
-
3,048 m)
High Altitude settings (2,000 ~ 10,000 ft)
1. With the Power
turned OFF, press the 'Modes button'
for 5 seconds to get into the Installer
Parameters Mode.
2. Turn the dial (E) until ‘9:HA’ appears.
3. Press the dial (E).
4. Set the high altitude value by turning the dial.
Refer to table.
5. Press the dial again (E) to save the setting.
6. Press the ‘Modes button’
for one second, to Save the number and to go back to initial status.
E
4.12 Gas High Altitude Setting
(no adjustment is needed below 2000 feet)
4.13
Gas Conversion.
5. Change dip switch 6 to OFF and 7 to ON. The unit
will cycle down to MIN fire.
6. Wait for your combustion analyzer to stabilize. Then
measure the CO
2
for MIN fire. Refer to Table 10 for
acceptable MIN fire combustion readings.
7. Open the gas valve adjustment port by removing the
cap screw with a 4mm Allen wrench
8. Use the Allen wrench to make a minor adjustment
(1/8) to increase or decrease CO
2
.
9. It may be necessary to go back and forth
between MAX fire and MIN fire several times
(making adjustments only at MIN fire) before
CO2 levels are acceptable. Be sure to put the
adjustment port cap screw back into the valve
when done.
10. Once the CO
2 and manifold pressure
measurements for both MIN and MAX fire are
acceptable per Table c, set dip switches 6 and
7 to the OFF position for nominal fire (normal
operation).
