Nortek REZNOR UDSBD 015-3 Guide

1611UDSBD-3GBEN
UDSBD 015-3, 020-3, 025-3, 030-3
Gas fired Balanced flue / Fan assisted flue
unit heater with centrifugal fan
These appliances meet the following EC Directives:
DIR 2009/142/EC:GAD
DIR 2014/30/EU:EMC
DIR 2014/35/EU:LVD
DIR 2006/42/EC:MD
INSTALLATION
COMMISSIONING
SERVICING
WARNING
Please read this document carefully before commencing installation, commissioning and/or servicing.
Leave it with the user or attached to the appliance or gas service meter after installation.
Improper installation, adjustment, alteration, service or maintenance can cause property damage, injury or death.
All work must be carried out by appropriately qualified persons.
The manufacturer does not take any responsibility in the event of non-observance of the regulations concerning
the connection of the apparatus causing a dangerous operation possibly resulting in damage to the apparatus and/or
environment in which the unit is installed.

1611UDSBD-3GBEN, Pag. 2/36
INDEX
Warnings ..........................................................................................................................3
1. General.......................................................................................................................4
2. Installation codes .......................................................................................................4
3. Warranty.....................................................................................................................4
4. Uncrating and preparation..........................................................................................4
5. Dimensions ................................................................................................................5
6. Technical data ............................................................................................................8
7. Flue requirements.......................................................................................................10
8. Unit heater location....................................................................................................15
9. Hanging the unit.........................................................................................................16
10. Gas piping and pressures ...........................................................................................17
11. Electrical supply and connections..............................................................................18
12. Check installation and start up...................................................................................20
13. Maintenance schedule................................................................................................24
14. Heat exchanger maintenance .....................................................................................25
15. Burner maintenance...................................................................................................26
16. Burner orifice.............................................................................................................28
17. Ignition system...........................................................................................................29
18. Blower motor.............................................................................................................29
19. Centrifugal fan...........................................................................................................33
20. Venter motor and wheel .............................................................................................30
21. Gas valve....................................................................................................................31
22. Combustion air pressure switch.................................................................................31
23. Limit controls.............................................................................................................32
24. Flue and combustion air system.................................................................................32
25. Troubleshooting .........................................................................................................34
26. Parts list......................................................................................................................35

1611UDSBD-3GBEN, Pag. 3/36
FOR YOUR SAFETY
What to do if you smell gas:
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any phone in your
building.
• Immediately call your gas supplier.
• Evacuate all personnel.
Warnings
FOR YOUR SAFETY
Do not store or use petrol or other flammable vapours and liquids in the
vicinity of this or any other appliance.
WARNING: Improper installation, adjustment, alteration, service or main-
tenance can cause property damage, injury or death. Read the installation,
operation, and maintenance instructions thoroughly before installing or
servicing this equipment.
WARNING :Do not use this appliance if any part has been immersed in water.
Immediately call a qualified service technician to inspect the appliance and
replace any gas control that hes been immersed in water.
WARNING : Gas-fired appliances are not designed for use in hazourdous
atmospheres containing flammable vapors or combustible dust, in atmospheres
containing chlorinated or halogenated hydrocarbons or in applications with
airborne silicone substances.
WARNING : Should overheating occur, or the gas supply fail to shut
off, shut off the manual gas valve to the appliance before shutting off the
electrical supply.
WARNING : This appliance is not intended for use by persons (including
children) with reduced sensory or mental capabilities, or lack of experience and
knowledge unless they have been given supervision or instruction concerning
use of the appliance by a person responsible for their safety. Children should
be supervised to ensure that they do not play with the appliance.

1611UDSBD-3GBEN, Pag. 4/36
This unit was test operated and inspected at the factory prior to crating and was in
proper operating condition. If the heater has incurred damage in shipment, document
the damage with the transport company and contact your supplier.
Check the rating plate for the gas and electrical specifications of the heater to be sure
that they are compatible with the gas and electric supplies at the installation site.
Read this booklet and become familiar with the installation requirements of your
heater. If you do not have knowledge of local requirements, check with the gas
supplier and any other local agencies who might have requirements concerning this
installation.
Before beginning, make preparations for necessary supplies, tools and manpower.
If the installation includes optional vertical louvers or downturn nozzle etc.,
install these options before the heater is suspended. Follow the instructions
included in the option package.
3. Warranty
4. Uncrating
and
preparation
Warranty is void if :
a. Wiring is not in accordance with the diagram furnished with the heater.
b. The unit is installed without proper clearances as soon as clearances are
required regardless of the material being combustible.
c. A fan model is connected to a duct system or if the air delivery system is
modified.
These units must be installed in accordance with BS6230 or BS5440 as appropriate
plus all local building codes.
1. General Models UDSBD 015-3 through 030-3 are design certified to the CE EN1020 stan-
dard for use in industrial and commercial installations only. All models and sizes
are available for use with either natural, propane or butane gas with operating tem-
perature between -15°C and 40°C. The type of gas, the input rate and the electrical
supply requirement is shown on the heater rating plate. Check the rating plate to
determine if the heater is appropriate for the intended installation.
This installation manual is shipped with the heater. Verify that the literature is cor-
rect for the heater being installed. If the manual is incorrect for the heater, contact
the supplier before beginning installation.
The instructions in this manual apply only to the models listed.
Installation should be done by a suitably qualified installer in accordance with
these instructions. The installer is responsible for the safe installation of the heater.
2. Installation
codes

1611UDSBD-3GBEN, Pag. 5/36
5. Dimensions & Clearances (horizontal orientation = standard)
Top view
Front view
Legend:
1. Combustion air inlet
2. Flue connection
3. External gas connection
4. Electrical connections
5. Service panel
Rear view
Side view
Figure 1a : UDSBD 015-3 -> 020-3
Table 1a : Dimensions (mm)
JG
K
H
R
12
43
P
M N
D
A C
U V
E
A1
Y
Z
X
5
UDSA-3 A A1 B C D E F G H J K L M N P Q R
015 383 460 700 343 404 935 546 199,5 191 139 122 86 413 15,5 98 350 120
020 383 460 700 343 404 935 546 199,5 191 139 122 86 413 15,5 98 350 120

1611UDSBD-3GBEN, Pag. 6/36
Figure 1b : UDSBD 025-3, 030-3
Top view
Front view
Rear view
Side view
J
G
K
H
R
12
4 3
Rear view mod. 035-2, 043-2 & 050-2
J
K
H
G
R
1 2
34
L
J
K
H
G
R
1 2
34
Rear view mod. 055-2 & 064-2
Table 1b : Dimensions (mm)
P
M N
B
A C
U V
E
A1
X
Y
z5
UDSA-3 A A1 B C D E F G H J K L M N P Q R
025-030 586 590 700 546 404 1185 546 367,5 191 222 122 121 413 15,5 98 350 140
Legend:
1. Combustion air inlet
2. Flue connection
3. External gas connection
4. Electrical connections
5. Service panel

1611UDSBD-3GBEN, Pag. 7/36
Clearances (mm) Units must be installed so that the minimum clearances in the following table are
provided for combustion air space, inspection and service and for proper spacing
from combustible materials.
Attention :
The clearance distance from the flue system must be minimum 150mm at all
points !
Combustion air
supply and flue
system diameters -
Diameter gas
connection
Table 2 : Clearances (mm)
Table 3 :
(*) : Heaters can be base mounted on suitable non combustible supports.
UDSA-3 015 020 025 030
Ø flue/ air inlet (mm) 80 80 100 100
Ø gas connection 1/2” 1/2” 1/2” 1/2”
UDSA-3 X Y Z (*) U V
015 - 030 100 130 50 270 850

1611UDSBD-3GBEN, Pag. 8/36
6. Technical
data The UDSBD-3 units are fitted with a new type of Nicotra blower with EC motor.
The blower can be used on a variety of different speeds. The motor speed is
adjustable by use of a potentiometer (see table below ).
The units leaving the factory are set to the speed requested by the customer. The
curves shown in the figures 2a/2b, illlustrate for each unit which speeds can be
chosen in order to get another air duty.
Table 4 : Technical data
1) Gas Appliance Classifications for Approved Venting Methods based on CEN-report CR1749:2001.
2) There is a difference between the gas connection diameter and the diameter of the supply line. Always use the most adequate diameter of the
supply line to minimize the pressure drop through the gas pipes - if necessary, reduce the diameter of the supply line at the inlet of the unit.
3) Figure for discharge louvre zero deflection.
4) Height from floor to bottom surface of heater. These are recommendations only. Positioning of unit heaters for proper performance is application
dependent. Operation is affected by other air moving equipment in the space, obstructions to the airflow, draughts and/or close proximity to
doors or windows, etc ... Care should be taken to avoid mounting the heaters above these recommendations, unless downturn nozzle options
are used, as significant stratification may occur resulting in poor floor coverage and higher energy losses through the roof structure.
5) Isothermal conditions +/-20°C ambient air temperature, discharge louvres zero deflection, v = 0,5m/s. The air throw will be influenced by the
height of the building, mounting height of the unit, ambient temperature & adjustment of the louvres.
6) Sound pressure level in dB(A) in free field conditions, measured at 5 meters from the unit, free outlet
7) Sound pressure level in dB(A), measured at 5 meters from the unit with A=160m² & Q=2, free outlet
Type UDSBD 015-3 020-3 025-3 030-3
Gas category II2H3+
Comb. air & ue, type B (1) B22
Comb. air & ue, type C (1) C12, C32, C42, C52, C62, C82
Dia ue outlet/combustion air inlet mm 80 80 100 100
Heat input Hs kW 17,6 22 30,8 35,2
Heat input Hi kW 15,9 19,8 27,8 31,7
Heat output kW 14,6 18,2 25,5 29,2
ermal eciency % 92 92 92 92
Gas consumption
natural gas G20 m³/h 1,68 2,1 2,94 3,36
propane G31 kg/h 1,24 1,55 2,16 2,47
Gas pipe connection (2) 1/2”
Temperature rise (3) K 20 23 27 25
Airow (3) m³/h 2150 2350 2750 3360
Recommended mounting height (4) m 3,5 4 4,5 4,5
Horizontal throw (5) m 18 23 26 26
Sound pressure (6) dB(A) 50 52 47 51
Sound pressure (7) dB(A) 57 58 54 58
Electrical service (protection IP20) 230/240V 1N ~50Hz
Max. total electrical rating W 496 496 1662 1662
Weight (net) kg 50 53 71 74

1611UDSBD-3GBEN, Pag. 9/36
Figure 2a : Blower curve for UDSBD 015-3/020-3
Figure 2b : Blower curve for UDSBD 025-3/030-3

1611UDSBD-3GBEN, Pag. 10/36
7. Flue
requirements
Model UDSBD-3 heaters may be installed as Type-B and Type-C installations.
Local requirements may apply in addition to national requirements. These unit
heaters are designed to operate safely and efficiently with either a horizontal or
verticalfluesystemwheninstalledwiththespecificrequirements and instructions.
If this heater is replacing an existing heater, be sure that the flue is sized properly
for the heater being installed and that the existing flue is in good condition. A
properly sized flue system is required for safe operation of the heater.An improp-
erly sized flue system can cause unsafe conditions and/or create condensation.
The air heaters may be installed as a balanced flue (type C) heater requiring both
a combustion air inlet duct and a flue pipe or as a power vented heater (type
B) (the combustion air is taken from the space where heater is installed), which
requires only a flue pipe exhausting to outdoors.
All products of combustion must be flued to outdoor atmosphere.
Each heater installed as a type B appliance must be fitted with an individual flue
pipe and the combustionair inlet opening is providedwith a protection grill. Each
heater installed as a type C appliance must be fitted with an individual combus-
tion air/flue pipe system. Type C2 appliance, with single duct system for supply
of combustion air and evacuation of flue gasses, are not allowed.
IMPORTANT :
Thefluemust beinstalled in accordancewithnationalandlocalregulations.
Failuretoprovideproperflueingcouldresultindeath,seriousinjury and/or
property damage. The air heatermust be installed with a flue to the outside
of the building. Safe operation of any power vented gas apparatus requires
a properly operating flue system, correct provision for combustion air and
regular maintenance and inspection.

1611UDSBD-3GBEN, Pag. 11/36
Table 5 : maximum flue system pipe lengths
Diameter & maximum
flue pipe lengths Flue pipe diameters and maximum pipe lengths in table 5 apply to both horizontal
and vertical systems. Add all straight sections and equivalent lengths for elbow.
The total combined length must not exceed the maximum flue length.
• Use only one diameter of flue pipe on an installation.
• Minimum flue is 1m.
Flue outlet Venter outlet attachment requirements:
Depending on the size of flue pipe as determined in table 5, attach either the flue
pipe directly to the collar or a taper-type connector.
Attention :
Single wall flue pipe exposed to cold air or run through unheated areas should be
insulated. Where condensation is unavoidable, provision must be made for the
condensation to flow freely to a point to which it can be released, i.e. a drain or
gully.Thecondensationdrainfromthefluemust be constructed from non-corrodible
material not less than 20 mm diameter. Copper or copper based alloys must not be
used for condensation drains.
The port must be at least 450 mm away from the air heater flue connection socket.
Follow the flue pipe manufacturers installation instructions for making joints, in-
cluding connections to the air heater, for passing through a building element and
for support requirements.
Single wall flue seamless aluminium or stainless steel pipes are required.All joints
must be sealed to prevent products of combustion from leaking into the building. If
the flue passes through a combustible element of the building it must be enclosed by
a sleeve of non-combustible material and separated from the sleeve by a minimum
of 25 mm air break. The temperature of any combustible material near to the flue
must not exceed 65°C when the heater is in operation. The flue must be at least
150 mm away from any combustible material.
Model UDSBD-3 015,020 025, 030
Heater socket & pipe dia mm flue pipe 80 100
inlet pipe 80 100
Max. straight length (with wall/roof terminal) m flue pipe 9 9
inlet pipe 9 9
Equivalent length of 45° elbow m flue pipe 0.75 0.75
inlet pipe 0.75 0.75
Equivalent length of 90° elbow m flue pipe 1.5 1.5
inlet pipe 1.5 1.5

1611UDSBD-3GBEN, Pag. 12/36
Flues for power
ventedinstallations
(type B appliances)
Figure 3a : Approved
appliances type B
If the air heater is to be installed as a type B appliance, air for combustion will be
taken from within the space where the heater is installed. Ensure that an adequate
air supply for combustion and ventilation is provided within the building in ac-
cordance with BS6230/BS5440 plus other relevant regulations & rules in force.
B22 - roof B22 - wall
Figure 3b :
Type B appliances :
Combustion air and flue
pipe sockets
1) Flue pipe outlet collar
2) Combustion air inlet opening
2
1
1
2
Models 025-3 & 030-3
Models 015-3 & 020-3

1611UDSBD-3GBEN, Pag. 13/36
Air supply It is important to ensure that there is an adequate air supply at all times for both
combustion and heating requirements. Modern buildings involve greater use of
insulation, improved vapour barriers, and weather proofing. These practices mean
that buildings are sealed much tighter than in the past.
Proper combustion air supply for a power vented Type B installation requires ven-
tilation of the heated space. Natural infiltration of air may not be adequate. Use of
exhaust fans aggravates this situation. It is important to ensure that there is adequate
combustion air supply at all times. Reliance on doors and windows is not allowed.
WARNING :
When these air heaters
are installed in type B
applications, designed to
take air for combustion
from the space in which
it is installed. Do not re-
strict the combustion air
intake.
Combustion air inlet
pipe & flue pipe
for balanced flue
installation (type C
appliances)
Balanced flue air heaters are designed to be fitted with a combustion air inlet duct
that obtains outdoor air and a flue pipe that exhausts flue products to outdoors.
Both the flue and combustion air pipes must be sealed. Use gasket sealed seamless
aluminium or stainless steel pipe or equivalent. For testing, the flue pipe should
include a sealable test port.
Type C2 appliances must not be applied !
Always ensure that adequate combustion air is provided to suit the total in-
stallation of all combustion equipment in accordance with BS6230 or BS5440
as appropriate.
Ensure that the air combustion inlet opening at the rear side of the unit cannot be
obstructed (cfr. fig. 3a).
C52
C32 / C62
C12 C12b/C62
Figure 4 : Approved
appliances type C

1611UDSBD-3GBEN, Pag. 14/36
Figure 5 : Type C appli-
ances : Combustion air
and flue pipe sockets
1) Flue pipe outlet collar
2) Combustion air pipe inlet collar
1
2
Models 015-3 &
020-3
2
1
Models 025-3 &
030-3
1
2
Models 035-2,
043-2 & 050-2

1611UDSBD-3GBEN, Pag. 15/36
The presence of chlorine vapours in the combustion air of gas-fired heating
equipment presents a potential corrosion hazard. Chlorine, found usually in the
form of freon or degreaser compounds when exposed to a flame will precipitate
from the compound, and go into solution with any condensation that is present
in the heat exchanger or associated parts. The result is hydrochloric acid which
readily attacks all metals. Care should be taken to separate these vapours from the
combustionprocess.Thismaybedone by wise location of theunit flueand combus-
tion air terminals with regard to exhausters or prevailing wind directions. Chlorine
is heavier than air. Keep this fact in mind when determining installation location
of the heater in relation to building exhaust systems.
Where chlorine vapours are prevalent heaters with special grade 316A1SI stainless
steel heat exchangers are recommended.
Hazards of
Chlorine -
apply to the
location of the
combustion air
inlet
8. Location
heater
Remark:
Flue requirements
may affect
location. Consult
section 7 before
making a final
determination.
WARNING: If touched, the vent pipe and internal heater surfaces
that are accessible from outside the heater will cause burns. Suspend
the heater such that these components cannot be touched.
Use the minimum clearances in section 5 and the throw data in the technical data
table of section 6 when determining where to suspend the heater.
CAUTION : Do not locate the heater where it may be exposed to water.
For best results, the heater should be placed with certain rules in mind. Always
ensure that minimum clearances are maintained. Locating a unit heater above the
maximum recommended height can result in significant air stratification. When
possible, heaters should be arranged to blow toward or along exposed wall surfaces.
Suspended heaters are most effective when located as close to the working zone as
possible, but care should be exercised to avoid directing the discharged air directly
on to room occupants.
Partitions, columns, counters, or other obstructions should be taken into consider-
ation when locating the unit heater so that a minimum quantity of airflow will be
deflected by such obstacles.
When units are located in the centre of the space to be heated, the air should be
discharged toward the exposed walls. In large areas, units should be located to dis-
charge air along exposed walls with extra units provided to discharge air in toward
the centre of the area. For optimum results heaters are best used in conjunction with
recirculating air fans suspended at high level.
At those points where infiltration of cold air is excessive, such as at entrance doors
and shipping doors, it is desirable to locate the unit so that it will discharge directly
toward the source of cold air, typically from a distance of 4.5 to 6.0 meters or install
a downflow unit over the door opening.

1611UDSBD-3GBEN, Pag. 16/36
9. Hanging
the heater
Warning : Do not place or add additional weight to the suspended heater.
Before suspending the heater, check the supporting structure to verify that it has
sufficient load-carrying capacity to support the weight of the unit as specified in
table 4.
WARNING:
Check the support-
ing structure to
verify that it has suf-
ficient load-carrying
capacity to support
the unit weight. Sus-
pend the heater only
from the threaded
nut retainers or
with a manufacturer
provided kit. DO
NOT suspend from
the heater cabinet
panels.
Be sure that the threaded hanger rods are locked to the heater as illustrated in
figure 6. Recommended maximum hanger rod length is 1.8m. Where longer drops
are required, ensure that restraints are fitted to prevent excess lateral movement
and supports are adequately sized.
Leave the unit on the pallet. If the bottom of the unit is not supported or protected
damage can occur.
Figure 6 : Suspending the heater with rods from the threaded nut retainers
Add a nut to lock the M10x1.5
hanger rod to the heater
The heater is supplied with four point suspension. All points must be used. Two
threaded nut retainers are provided on each side of the top of the heater. See figure
6 for hanger rod size.
Detail

1611UDSBD-3GBEN, Pag. 17/36
Warning : This appliance is equipped for a maximum gas supply pressure
of 50 mbar.
Warning : Pressure testing supply piping
Test pressuresabove50mbar:Disconnect the heater and manual valve from the
gas supply line which is to be tested. Cap or plug the supply line.
Test pressures below 50mbar : Before testing, close the manual valve on the
heater.
10. Gas Piping
and
pressures
All piping must be in accordance with requirements outlined in the National Gas
Codes (different for each country). Gas supply piping installation should also
conform with good practice and any local codes. Support gas piping with pipe
hangers, metal strapping, or other suitable material. Do not rely on the heater to
support the gas pipe.
All sealing products shall be resistant to the action of liquefied petroleum gas or
any other chemical constituents of the gas being supplied.
Install a ground joint union and manual shutoff the gas cock upstream of the unit
control system.
The unit is equipped with a nipple that extends outside the cabinet. Leak test all
connections by brushing on a leak detecting solution.
WARNING: All
components of a
gas supply system
must be leak tested
prior to plac-
ing equipment in
service. NEVER
TEST FOR LEAKS
WITH AN OPEN
FLAME. Failure to
comply could result
in personal injury,
property damage or
death.
Diameter gas
connection
Figure 7 : gas connection
Table 6 : diameter gas connection
WARNING :
Do not over tighten
and do not rotate
thegasvalveinside
the heater control
compartment.
Type 015-3 through 030-3
Nat. gas G20
Propane G31 1/2

1611UDSBD-3GBEN, Pag. 18/36
11. Electrical
supply and
connections
The electrical installation may only be carried out by an appropriately qualified
person current to IEE Regulations. The supply line to the heater should include
a main switch. The minimum clearance distance between the contacts must be
more than 3 mm.
All electrical connections should be made in the heater control compartment
(refer to figure 8). Screw type terminals are provided. Connections should be in
accordance with the terminal markings and the wiring diagram affixed to the air
heater.
Attention :
Seriousdamagecanoccurto burnerrelaywhenfaultyconnectionofthermostat,
reset switch or burner failure lamp. Switching of wires for reset switch and
flame failure (e.g in a remote control box) will destroy the burner relay.
The minimum external control required for the air heater is a room thermostat.
It is essential that the main input line and neutral to terminals L and N
remain live at all times even when the heater is switched off to ensure
correct operation of the unit.
A polarisation switch with green indicator light is fitted inside the heater to
check if Line, Neutral and Earth are connected correctly. If this is the case, the
green light will glow when pushing on the switch. If the light does not glow,
check earth, line and neutral connections.
A burner reset switch with red indicator light is fitted on the heater. To add a
remote reset button, make connections to the terminals in the electric box as
indicated on the wiring diagram.
IMPORTANT: If the reset button requires activating for any reason, the
cause must be determined. After determining and correcting the problem,
restart the heater and monitor long enough to ensure proper operation
(approx. 5 minutes).
An orange indicator light is fitted on the heater to signify when the burner is on.
DANGER :
THIS APPLIANCE
MUST BE
EARTHED.
Thermostat
location Do not attempt to control more than 1 air heater from a single thermostat or
control panel unless a properly wired relay is fitted. Follow the instructions
supplied with such panels.
The location of the room thermostat or sensor is very important. It should not
be positioned on a cold wall or cold surface. Avoid location in draughty areas or
where it may be influenced by heat sources e.g. the sun, process plant, etc. The
thermostat should be mounted on a vibration free surface and mounted about 1,5
metres above floor level. Follow the thermostat manufacturers instructions. The
thermostat must be suitable for potential free contacts.
Ensure that all cables and installers wiring are fixed to the gas pipe and that they
do not touch the combustion collector box.

1611UDSBD-3GBEN, Pag. 19/36
Figure 8 : Wiring connections on the terminal board (only for illustrative purposes)

1611UDSBD-3GBEN, Pag. 20/36
12. Check
installation
&
start-up
Check the instal-
lation prior to
start-up
Heater start-up
Checksuspension. Unit must be secure.Verify that no other partsare fitted which
are not individually supported and secured.
Check clearances from combustibles. Requirements are in section 5.
Check vent system to be sure that it is installed according to the instructions in
section 7, venting requirements.
Check piping for leaks and proper gas line pressure. Bleed gas lines of trapped
air.
Check electrical wiring andensure that wiring conforms withthe wiring diagram.
Be sure all wire sizes meet requirements.
Check polarity. Verify that line voltage exists between the black “L1” and earth
ground.
Verify that the appliance is earthed by conducting an earth continuity test.
WARNING:
For your safety, follow the instructions exactly otherwise damage or injury
could occur.
• This heater does not have a pilot flame. It is equipped with an ignition device
which automatically lights the burner. Do not try to light the burner by hand.
• Before operating, smell all around the heater area for gas. Be sure to smell
next to the floor because propane gas is heavier than air and will settle near
the floor.
•Do not use this appliance if any part has subjected to water ingress.
Immediately call a qualified service technician to inspect the appliance and
to replace any part of the control system and any gas control.
•When overheating occursor when gas supply isnot turned off, shut themanual
gas tap before turning off the electric power.