UHD S
TANDARD
D
UCT
F
URNACE
I
NSTALLATION
O
PERATION
AND
S
ERVICE
M
ANUAL
24
SECTION 11: USER INSTRUCTIONS
11.1 User Instructions
The UHD[X][S][R] Series heaters are fully automatic
and operate from the external controls fitted on site.
11.2 Heater Operation
When the heater has been switched on by the
thermostat installed on site, the main burner will
automatically turn on.
The burner control box will control the safe ignition
of the flame.
All heaters require a constant gas and electricity
supply which must not be interrupted during the
normal operation of this heater.
11.3 Lighting Instructions
11.3.1 To Turn On Heater
1. Ensure that the electrical and gas supplies to
the heater are on. Check that the on site
controls are
"
ON
"
.
IMPORTANT:
The thermostat setting must be above
the ambient temperature for the heater to operate.
The automatic firing sequence will begin as
described
on Page 22, Figure 11
. The heater will
now operate automatically under the control of the
on site controls.
11.3.2 To Turn Heater Off
Set the thermostat to the
"
OFF
"
position.
The burner will turn off immediately.
To restart, turn the thermostat above room
temperature.
11.4 Simple Troubleshooting
Some possible reasons for the heater not operating
are:
1. Gas supply not
"
ON
"
.
2. Electricity supply not
"
ON
"
.
3. The time and/or temperature controls are not
"
ON
"
.
4. A limit switch may have operated. This may be
caused by an interruption of the electrical
supply, failure of the distribution fan or vent or
heat exchanger blockage.
If a temperature limit switch persistently trips, there
is a fault which must be investigated by a contractor
qualified in the installation and service of gas-fired
heating equipment.
11.4.1 Simple Troubleshooting (Burner Faults)
If the burner fails to ignite for any reason, it will retry
for ignition (four trials total). After four unsuccessful
ignition trials, the control will put the heater into
lockout for one hour.
Lockout should not occur during normal operation of
the heater and indicates there is a fault condition
which must be corrected. There is an LED light on
the ignition control that flashes codes to assist in
fault correction.
See Page 24, Figure 13
for LED
indication codes.
Figure 13: LED Diagnostic Codes
WARNING
Explosion Hazard
Installation, service and annual inspection
must be done by a contractor
q
ualified in
the installation and service of
g
as-fired
heatin
g
e
q
uipment or your
g
as supplier.
Turn off
g
as and electrical supplies before
performin
g
service or maintenance.
Failure to follow these instructions can
result in death, injury or property dama
g
e.
LED INDICATION FAULT MODE
Slow Flash
Normal Operation - No call for heat.
Fast Flash
Normal Operation - Call for heat.
2 Flashes
Ignition Lockout - No flame detected.
3 Flashes
Airflow Fault - Pressure switch open or closed.
4 Flashes
Temperature Limit or
Switch Open
5 Flashes
Flame Sense Error - Gas valve not energized.
Steady On
Internal Control Failure
