Honeywell HeatStar HSU50 E-Manual page 4

FUEL CONVERSION Section 2: FUEL CONVERSION INSTRUCTIONS
WARNING: Explosion Hazard
Turn off the gas supply to the heater before perform-
ing any service or maintenance.
Failure to follow these instructions will result in death,
injury or property damage.
WARNING: Electrical Shock Hazard
Unplug the electrical cord from the outlet before
performing any service maintenance.
Failure to follow these instructions will result in death,
injury or property damage.
The electrode and sensor are not adjustable. DO
NOT change location or position as part of this
conversion kit.
This conversion kit shall be installed by a qualified service
agency in accordance with the manufacturer's instructions
and all applicable codes and requirements of the authority
having jurisdiction. If the information in these instructions is
not followed exactly, a fire, explosion or production of carbon
monoxide may result causing property damage, personal injury
or loss of life. The qualified service agency performing this work
assumes responsibility for the proper conversion of this appliance
with this kit.
FIGURE 10
WARNING
Compact Unit Heater
4 screws
Step 1
CAUTION THE UNIT MUST NOT BE CONNECTED TO EITHER
THE GAS SUPPLY OR THE ELECTRICAL POWER SUPPLY, BEFORE
PROCEEDING WITH CONVERSION.
Step 2
Remove and retain the four screws holding the manifold on to the
burner box (Figure 10). Rotate the valve/ manifold assembly, away
from the burners (Figure 11). The valve/manifold assembly holds the
orifices (3 orifices on unit HSU50/MHU50, 5 orifices on unit HSU80/
MHU80, 8 orifices on unit HSU125/MHU125). This will allow access
to the orifices on the manifold, and also the adjustment spring in the
valve/regulator.
Step 3
Remove and discard the adjustment spring cap from gas valve/
regulator with a flat blade screw driver by turning the screw counter-
clockwise. Remove and discard the regulator adjustment screw found
under the cap. Remove and discard the spring that is located under
the adjustment screw. Take the spring kit from the conversion kit,
and compare the part number of the kit to the parts list on page 3. If
it does not match, immediately contact Heatstar, Inc. for the correct
kit. After confirming the spring kit is correct for the heater model you
are converting, install the new spring and adjustment screw. Turn
spring adjustment screw clockwise (in) until the screw stops, then turn
it counter-clockwise (back) 1 ½ turns. Place conversion label supplied
with the spring kit on the valve near the adjustment screw cover
opening.
Step 4
Remove and discard the orifices (3 orifices on unit HSU50/MHU50,
5 orifices on unit HSU80/MHU80, 8 orifices on unit HSU125/
MHU125) from the manifold with using a ½ " open end wrench. Turn
them counter-clockwise to remove. Take the new orifices from the
conversion kit and before installing, confirm that the number stamped
on the side of the orifice matches the number for the kit being
installed. If it does not, immediately contact Heatstar, Inc. for the
correct kit. If they are the correct orifices, install them in the manifold
using caution not to cross thread.
E-4
Fuel Conversion Manual
FIGURE 11