Enerco MHU 45 - Manual (Page 9)

9 Operating Instructions and Owner’s Manual Enerco | Compact Unit Heater
5. Test for spillage at the draft hood relief opening after five
minutes of main burner operation. Use the flame of a
matchor candle, or smoke from a cigarette, cigar, or pipe.
6. After it has been determined that each appliance remaining
connected to the common venting system properly vents
when tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other gas-burning
appliance to their previous condition of use.
7. If improper venting is observed during any of the above tests,
the common venting system must be corrected. The common
venting system should be resized to approach the minimum
size as determined by using the appropriate tables in
Appendix G in the current standards of the National FuelGas
Code, ANSI Z223-1 in the U.S.A. and the appropriate
Category I Natural Gas and Propane appliances venting sizing
tables in the current standards of the CSA B149.1 Natural Gas
and Propane Installation Code in Canada.
NOTE Local codes may supersede any of the above provisions.
ELECTRICAL CONNECTIONS
NOTE The MHU/HSU series unit heaters use a direct spark
ignition system. There is no pilot necessary as the spark lights the
main burner as the gas valve is turned on. The direct spark ignition
N
MANUAL
MAIN SHUT-OFF VALVE
(FURNISHED BY INSTALLER)
GAS SUPPLY CONNECTION
GAS FLOW
DRIP LEG
1/8 NPT
PLUGGED TAP
GROUNDED
JOINT UNION
LINE VOLTAGE FIELD WIRING
UNIT
BLACK
BLACK
WHITE
WHITE
EQUIPMENT
GROUND
BLACK WIRE WITH WHITE TAPE OR
WHITE WIRE WITHOUT TAPE
L1
FIGURE 7
GAS SUPPLY TO UNIT HEATER
ISOLATE
GAS VALVE
MANUAL MAIN SHUT-OFF
VALVE WILL NOT HOLD
NORMAL TEST PRESSURE
CAP
UNIT HEATER
FIGURE 8
FIGURE 9
WARNING
Electric shock hazard. Can cause injury
or death. Do not use this heater if any
part has been under water. Immediately
call a qualified service technician to
inspect the furnace and to replace any
part of the control system and any gas
control which has been under water.
WARNING
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at
disconnect switch(es). Unit may have
multiple power supplies.
WARNING
Danger of explosion and fire. Can
cause injury or product or property
damage. You must follow these
instructions exactly.
WARNING
Danger of explosion. Can cause injury or
product or property damage. If over-
heating occurs or if gas supply fails to
shut of f, shut off the manual gas valve
to the appliance before shutting of f
electrical supply.