Powrmatic OUH series User guide

Stamm International Corporation
PO Box 1929
Fort Lee, NJ 07024
Tel: [phone]
Fax: [phone]
E-mail: [e-mail]
Stamm International HQ
www.powrmatic.co.uk
www.powrmatic.co.uk
®
Powrmatic Limited
Hort Bridge, Ilminster
Somerset
TA19 9PS
tel: [phone]
fax: [phone]
e-mail: [email protected]
web: www.powrmatic.co.uk
Powrmatic Ireland
45 Broomhill Close
Tallaght
Dublin 24
tel: [phone]
fax: [phone]
e-mail: [email protected]
web: www.powrmatic.ie
Getting In Touch
Powrmatic pursues a policy of continues improvement in both design and performance of its products and therefore reserves the right to change, amend or
vary specifications without notice. Whilst the details contained herein are believed to be correct they do not form the basis of any contract and interested
parties should contact the Company to confirm whether any material alterations have been made since publication of this brochure.
EURO-AIR
QUALITY
ICOM
Energy Association
More information is available from our website by scanning the following QR code.
OUH
User, Installation & Servicing Manual
Issue 5.8 Apr 2020
Doc Ref: M105 Issue 5.8 Apr 2020
ErP COMPLIANT
SEPTEMBER 2018

page no. 2 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
www.powrmatic.co.uk
Important: This certificate
must be kept with the appliance
Failure to provide a copy of the commissioning sheet invalidates the heater warranty
----------------------------------------------------
Powrmatic Ltd, Hort Bridge, Ilminster, Somerset, TA19 9PS
Tel: [phone] Fax: [phone]
Web: www.powrmatic.co.uk e-mail: [email protected]
This is to certify that this heater is guaranteed for two years parts and one year labour from the date
of original commissioning. The heater must be commissioned within 4 weeks of installation.
To make a claim
In the first instance you must contact your appliance supplier, or installer and provide:-
1. The appliance type and serial number.
2. The original commissioning documentation. As much detail as possible on the fault.
3. Your supplier, or installer, will then contact Powrmatic to make a guarantee claim on your behalf.
Conditions of Guarantee
1. The heater must have been installed by a competent qualified installer, and in
accordance with the manufacturer’s instructions, building regulations and local regulations.
2. The heater has been professionally commissioned, within 4 weeks of installation, and a copy of
the commissioning sheet returned to Powrmatic.
3. The heater has been maintained on a yearly basis by a competent and qualified servicing
company.
4. The heater has been used in accordance with the manufacturer’s instructions.
5. The correct specification fuel has been used.
6. No unauthorised repairs of modifications have been made. Powrmatic ‘General Conditions of
Sales’ have been observed.
7. Except for the obligation of Powrmatic Ltd to perform warranty repairs during the guarantee
period, Powrmatic will not be liable in respect of any claim for direct or indirect consequential
losses, including loss of profits or increased cost arising from loss of use of the heater, or any
event arising there from.
Exclusions
Consumables such as gaskets, ignition electrodes, flame rectification electrodes, drive belts, fusible
links, control batteries are all excluded from guarantee.
CertificateOfGuarantee
Certificate of Guarantee
®

page no. 3 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
Title Section Contents Page
User Instructions 4
Pre Installation
1.1 Introduction 5
Duties 6
Dimensions 7
1.2 Technical data 8
1.3 General Requirements 10
Installation
2.1 Fitting the unit 14
2.2 General Identication of Items 16
2.3 Fitting the Flue 17
2.4 Electrical Cable Installation 18
2.5 Wiring Diagram 21
2.6 Commissioning and Testing 22
2.7 Servicing 24
Additional Documents
3.1 Fault Finding 28
3.2 List of Parts 29
3.3 Oil Conversion 31
Appendices
Information required for ecodesign (ErP) Directive 2009/125 33
Users,InstallationandServicingInstructions
CONTENTS
Contents
Powrmatic oil fired heaters are only designed for operation
with either certified Gas Oil to BS2869 Class A2 or D, (also
referred to as 35 sec Oil’ or ‘Red Diesel’) and Kerosene to
BS2869 Class C2, (also referred to as ‘28 sec Oil’).
Powrmatic are not able to confirm the suitability of any alternative
blended Industrial Heating Oil (IHO) used to fuel their appliances and as
such will affect the warranty on the appliance.

page no. 4 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
Complete step 1 above.. Wait approximately 4-5 minutes
for the main air fan of the heater to stop running and the
turn off the oil supplies and electric supplies to the heater.
D) Description of Operation
Important: The heater must NOT be
controlled by switching ON and OFF the
main electrical supply to it.
1) Standard Units
The burner start up sequence will commence when the
controls e.g. Timeclock, room thermostat etc. call for
heat. The burner air fan will run and after a pre purge
period the burner will light. The heat output will then be
controlled either to high fire or low fire depending on the
requirements of the space being heated and the external
controls fitted.
Approximately 2/3 minutes after the burner lights the
heater fan will automatically start. When the external
controls are satised the burner will be turned o and
approximately 4/5 minutes later the heater fan will
automatically stop.
2) Modulating Units
When the burners are alight, the heat output will be
controlled to any point between high and low fire;
depending on the requirements of the space being heated
and the external controls fitted.
3) Summer / Winter Modes
Certain types of external controls will provide for two
modes of operation i.e:
Summer: The heater fan alone will run at the dictate of
the external controls to provide air movement.
Winter: The heater will operate normally.
4) Fan/Limit Stat
The fan and limit controls are mounted on the top of the
air heater.
i) Main Air Fan MAN/Auto
When the white button is pushed to MAN the fan will run
continuously i.e not controlled by any external controls
e.g. Timeclock. When the white button is pulled out the
fan will start and stop automatically in conjunction with
the burner.
ii) Limit Thermostat
This operates if high temperatures within the heater are
detected, the burner is turned off and a red indicator
light on the front of the heater is illuminated. The fault
condition must be identified and rectified and the
thermostat manually reset.
If the heater has not been left operational
proceed as follows.
A) Checks before operating the Air
Heater
The following preliminary checks should be made before
lighting the heater(s)
a) Ensure that the ELECTRICAL supply to the heater is
switched OFF.
b) Check that any warm air delivery outlets are open.
c) Check that the thermostat is set.
d) Check that the clock control is set to an ON period.
e) Check that any other controls are calling for heat.
B) Operating the Air Heater
1. Switch on the electrical supply at the isolator.
2. If the Limit indicator light comes on press the reset
switch the electrical box on top of the heater.
3. The burner air fan will run and after a pre purge period
of approximately 30 seconds the ignition spark will be
generated and the oil valve opened. The main burner will
then start.
4. If the main burner fails to light the burner will go to
lockout and the lockout indicator / reset button on the
burner control box will be illuminated. To restart the
burner push the lockout reset button.
NOTE: If the burner fails to light it will go to
lockout and the lockout indicator / reset
button on the burner control box will be
illuminated. To restart the burner push the
reset button.
If the unit will not light after two to three
attempts then shutdown the unit and call in
a service engineer.
C) To Shut Down the Air Heater
1) For Short Periods:
Turn the room thermostat to the OFF, or set to 'Summer
Mode'.
2) For Long Periods:
UserInstructions

page no. 5 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
When the unit has cooled push the reset switch on the
front of the heater to reset the limit thermostat interlock
relay, the red indicator light will go out and the unit is
operational again.
NOTE: The limit thermostat(s) can only be
reset once the unit has cooled down. Unless
the cause of the fault condition is readily
obvious, for example a power cut whilst the
heater was operating, a service engineer
should be contacted.
E) Maintenance
To maintain efficient, reliable and safe operation of the
heater it must serviced annually by a qualified person
Regular servicing is essential to maintain efficient, reliable
and safe operation of the heater. Users are strongly
recommended to have the heater serviced at least
annually and preferably at the end of the heating season.
IMPORTANT
Free access must be maintained to and
around the heater for servicing purposes
and the air supply to the heater must not be
restricted in any way. Combustible materials must not
be stored adjacent to the heater.
IMPORTANT
All Powrmatic heaters use either gas or oil
plus electricity to power them, they may also
contain moving parts such as pulleys and
The Powrmatic OUH Range is a range of oil fired forced
draught, closed flue, fanned circulation air heaters having
an output range of 20kW to 60kW .
The heaters are designed for suspension from suitable
roof points, or alternatively mounted on purpose designed
wall brackets, and are intended for heating commercial or
industrial premises.
The OUH-F has an axial type fan assembly fitted at the
rear of each heater to circulate the air being heated across
the combined combustion chamber/ heat exchanger. A
centrifugal fan variation is presented in the OUH-C range
for ducted applications. The OUH-D range, in having no
fan fitted, allows for ducted use where the air moving unit
is remote from the heater.
All units are fired with a forced draught packaged oil
burner complete with all necessary safety controls. Each
air heater must be connected to an individual closed flue
system only.
UserInstructions
Fuel Types
Oil fired units are supplied as standard for use with
certified Gas Oil to BS2869 Class A2 or D, (also referred to
as 35 sec Oil’ or ‘Red Diesel’) and can be supplied for use
with Kerosene to BS2869 Class C2, (also referred to as
‘28 sec Oil’). as an option.
IMPORTANT: Powrmatic are not able to
confirm the suitability of any alternative
blended Industrial Heating Oil (IHO) used to
fuel their appliances and as such will affect
the warranty on the appliance.
IMPORTANT
Service and Maintenance Engineers shall
ensure that replacement items are fitted,
adjusted and set in accordance with the
data and detail set out in these instructions. If in doubt
consult Powrmatic Technical Department.
1.1Introduction
belts. It would be hazardous to tamper with or attempt to
service unless you are a competent person in the field of
Gas and Electrical work.
Danger: Electricity
Warning: Flammable Materials
Warning: Hot Surfaces
Warning: Contains Moving Parts
Read and understand this Service Manual
Instructions before operating or servicing
this appliance
If you have any safety questions reference the servicing
and installation of any of our heaters please do not
hesitate to contact our head office for expert advice.
Your safety is paramount to us.

page no. 6 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
Notes:
Fuel Consumption and input figures based upon nett calorific values as follows:
- Class D light distillate fuel oil Nett CV 36.28 MJ/l
-
• Heaters have efficiency levels which meet with the minimum heater efficiency requirements of UK Part L Building Regulations
• Air handling data is assessed at room ambient conditions
• Throw figures provide the distance to the point where the terminal velocity degrades to 0.25m/s
• Noise levels are applicable to standard OUH models and are measured 5m from appliance in a typical installation situation.
• Motor kW, run and start amps apply to standard electrical supply as stated. For optional data contact sales office.
* For extended combustion duct lengths please contact Powrmatic
Model 20 30 45 60
Output High Fire (max) kW 20.0 30.0 45.0 60.0
Low Fire (min) kW 16.4 24.2 33.7 45.2
Input (nett CV) High Fire (max) kW 21.7 31.7 53.0 66.8
Low Fire (min) kW 17.5 26.0 37.1 50.9
Airflow
Volume OUH F m3/s 0.7 0.82 1.19 1.94
OUH C m3/s 1.0 0.82 1.19 1.88
Throw OUH F m 10 16 25 34
Fan Static OUH C Pa 275 305 275 384
Electrics
Supply Standard V/ph/Hz 230/1/50
Optional V/ph/Hz 415/3/50
OUH F Run amp 0.94 0.46 0.48 1.70
OUH C Motor kW 0.55 0.55 1.1 1.5
Run amp 4.30 4.33 5.54 8.0
Fuel Oil
Connection BSP/Rc ¼
Consumption
High Fire (max) kg/h 1.83 2.67 4.47 5.63
l/h 2.18 3.18 5.32 6.70
Low Fire (min) kg/h 1.47 2.20 3.13 4.29
l/h 1.75 2.62 3.72 5.11
Mounting Height OUH F Min m 2.50 3.00
Max m 3.00 5.00
Overall
Dimensions
Height mm 806 1043 1049 1049
Width mm 555 780 780 780
Depth OUH F mm 868 1106 1115 1150
OUH C mm 1163 1470 1469 1469
Installation Clearances
Top mm 1000
Side mm 500
Rear mm 400
Flue diameter mm ø 100 125
Combustion Air Spigot mm ø 150
Maximum Combustion Duct Length * m 120 100 81 21
Noise Level - OUH F models dB(A) 46 54 52 53
Nett Weight OUH F kg 53 126 126 126
OUH C kg 91.5 142 142 142
Technical Specification
OUH

page no. 7 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
OUH F 20 - Axial Fan
Model A B C D E F G K M
OUH F 20 668 555 610 100 465 101 549 200 196
Model A B C D E F G K M
OUH F 30 975 780 847 125 490 276 490 131 196
OUH F 45 975 780 847 125 490 276 490 140 202
OUH F 60 975 780 847 125 490 276 490 175 202
Model A B C D E F G H J L M
OUH C 20 668 555 610 100 465 101 549 410 340 495 196
Dimensions
OUH
OUH C 20 - Centrifugal Fan
OUH F 30/45/60 - Axial Fan
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
A A
B B
C C
D D
E E
F F
"Title Here"
OUH F 20 - Axial Freeblowing Fan
SCALE: 1:10SHEET 1 OF 1 "Description Here"
"Material Gauge & Spec Here"
ISSMODIFICATIONSDATEDCRI/ADRN
UNSPEC. TOLS.
Hole centers ±0.1mm
General ±0.1mm
Finished sizes ±0.1mm
MM
-
DO NOT SCALE
This drawing is copyright and the property of POWRMATIC
LIMITED. It must not be used without their knowledge, nor
communicated to any other person or company.
Powrmatic Ltd. Hortbridge, Ilminster. Somerset.
TA19 9PS.
Tel: [phone] Fax: [phone]
Web: www.powrmatic.co.uk E mail: r&d@powrmatic .co.uk
POWRMATIC LTD
01
NEW DRAWING02/01/2019
--
chrisbromfield
TITLE:
DESCRIPTION:
DRAWING NUMBER:
MATERIAL GAUGE & SPEC:
SALVAGNINI:
MATERIAL REQUIRED:
PROJECTION:
UNITS:
G
B
CM
A K
E FF ØD
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
A A
B B
C C
D D
E E
F F
"Title Here"
OUH F 30-45-60 - Axial Freeblowing Fan
SCALE: 1:10SHEET 1 OF 1 "Description Here"
"Material Gauge & Spec Here"
ISSMODIFICATIONSDATEDCRI/ADRN
UNSPEC. TOLS.
Hole centers ±0.1mm
General ±0.1mm
Finished sizes ±0.1mm
MM
-
DO NOT SCALE
This drawing is copyright and the property of POWRMATIC
LIMITED. It must not be used without their knowledge, nor
communicated to any other person or company.
Powrmatic Ltd. Hortbridge, Ilminster. Somerset.
TA19 9PS.
Tel: [phone] Fax: [phone]
Web: www.powrmatic.co.uk E mail: r&d@powrmatic .co.uk
POWRMATIC LTD
01
NEW DRAWING21/12/2018
--
chrisbromfield
TITLE:
DESCRIPTION:
DRAWING NUMBER:
MATERIAL GAUGE & SPEC:
SALVAGNINI:
MATERIAL REQUIRED:
PROJECTION:
UNITS:
A K
ØD
E F
G
B
M
C
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
A A
B B
C C
D D
E E
F F
"Title Here"
SCALE: 1:10SHEET 1 OF 1 "Description Here"
"Material Gauge & Spec Here"
ISSMODIFICATIONSDATEDCRI/ADRN
UNSPEC. TOLS.
Hole centers ±0.1mm
General ±0.1mm
Finished sizes ±0.1mm
MM
-
DO NOT SCALE
This drawing is copyright and the property of POWRMATIC
LIMITED. It must not be used without their knowledge, nor
communicated to any other person or company.
Powrmatic Ltd. Hortbridge, Ilminster. Somerset.
TA19 9PS.
Tel: [phone] Fax: [phone]
Web: www.powrmatic.co.uk E mail: r&d@powrmatic .co.uk
POWRMATIC LTD
01
NEW DRAWING02/01/2019
--
chrisbromfield
TITLE:
DESCRIPTION:
DRAWING NUMBER:
MATERIAL GAUGE & SPEC:
SALVAGNINI:
MATERIAL REQUIRED:
PROJECTION:
UNITS:
H
J
B
CM
G
50 A L
ØD
FEF

page no. 8 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
Model A B C D E F G H J L M
OUH C 30 975 780 847 125 490 276 490 636 418 495 196
OUH C 45 975 780 847 125 490 276 490 636 418 494 202
OUH C 60 975 780 847 125 490 276 490 636 418 494 202
MODEL Burner
Type Nozzle Pump
Pressure
Head
Setting
Combustion
Air
Nominal
CO2 NOx Nett Flue Temp
Danfoss bar p.s.i. no. no. (mm) %ppm °C
OUH20 RG1 RKD 0.50Gal 60° S
High Fire 12.41 180 0.3 1.0 12.56 84.3 193
Low fire 8.27 120 0.3 0.2 12.46 74.6 135
OUH30 RG1 RKD 0.75Gal 60° S
High Fire 12.07 175 1.3 2.2 12.55 63.2 171
Low fire 8.96 130 1.3 0.5 12.58 65.4 150
OUH45 RG2D 1.10Gal 60° S
High Fire 15.17 220 3.0 1.0 12.45 72.7 249
Low fire 8.27 120 3.0 0.25 12.52 65.3 196
OUH60 RG2D 1.25Gal 45° S
High Fire 15.17 220 4.0 412.73 59.8 300
Low fire 8.27 120 4.0 0.7 12.16 52.8 232
Riello Burner Settings - 35sec Oil - Diesel - Net CV (Hi = 42.69MJ/kg)
Notes: CO2 values and Nett flue gas temperatures are given for guidance and measured values will depend on site conditions.
OUH C 30/45/60 - Centrifugal Fan
1.2 Technical Data
Dimensions
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
A A
B B
C C
D D
E E
F F
"Title Here"
OUH C 30-45-60 - Centrifugal Fan Unit
SCALE: 1:10SHEET 1 OF 1 "Description Here"
"Material Gauge & Spec Here"
ISSMODIFICATIONSDATEDCRI/ADRN
UNSPEC. TOLS.
Hole centers ±0.1mm
General ±0.1mm
Finished sizes ±0.1mm
MM
-
DO NOT SCALE
This drawing is copyright and the property of POWRMATIC
LIMITED. It must not be used without their knowledge, nor
communicated to any other person or company.
Powrmatic Ltd. Hortbridge, Ilminster. Somerset.
TA19 9PS.
Tel: [phone] Fax: [phone]
Web: www.powrmatic.co.uk E mail: r&d@powrmatic .co.uk
POWRMATIC LTD
01
NEW DRAWING21/12/2018
--
chrisbromfield
TITLE:
DESCRIPTION:
DRAWING NUMBER:
MATERIAL GAUGE & SPEC:
SALVAGNINI:
MATERIAL REQUIRED:
PROJECTION:
UNITS:
J
H
B
143
CM
GE F
ØD
50 A L

page no. 9 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
/F Models /CCF Models
MODEL
Start Amps
(A) Run Amps (A) Fuse / MCB
Rating (A) Motor kW Start Amps (A) Run Amps (A) Fuse / MCB
Rating (A)
OUH20 2.26 0.94 3 / 6 0.55 10.75 4.3 6 / 6
OUH30 1.14 0.46 3 / 6 0.55 10.82 4.33 6 / 6
OUH45 1.7 0.48 3 / 6 1.1 13.85 5.54 10 / 10
OUH60 (35s) 4.2 1.7 3 / 6 1.1 20.0 8.0 10 / 10
OUH60 (28s) 4.2 1.7 3 / 6 1.1 24.4 9.76 13 / 13
Electrical Loadings - 1Pha
MODEL Air Volume External
Static
Pressure Throw Maximum
Duct
Resistance Fan Motor Noise
Level Weight
m³/s m³/h Pa mPa kW dB(A) kg
OUH20 F0.70 2520 n/a 8.5 n/a 0.26 46 53.0
CCF 1.0 3600 275 n/a 275 0.42 TBA 91.5
OUH30 F0.82 2952 n/a 16 n/a 0.13 54 126
CCF 0.82 2952 305 n/a 305 1.1 TBA 142
OUH45 F1.19 4284 n/a 25 n/a 0.27 52 126
CCF 1.19 4284 275 n/a 275 1.1 TBA 142
OUH60 F1.94 6984 n/a 34 n/a 0.27 53 126
CCF 1.88 6768 384 n/a 384 1.1 TBA 142
Heater Specifications
MODEL Burner
Type Nozzle Pump
Pressure
Head
Setting
Combustion
Air
Nominal
CO2 NOx Nett Flue Temp
Danfoss bar p.s.i. no. no. (mm) %ppm °C
OUH20 RG1 RKD 0.55Gal 45° S
High Fire 10.0 144 0.3 1.0 12.56 84.3 193
Low fire 7.0 100 0.3 0.2 12.46 74.6 135
OUH30 RG1 RKD 0.85Gal 45° S
High Fire 10.0 144 1.3 2.2 12.55 63.2 171
Low fire 7.0 100 1.3 0.5 12.58 65.4 150
OUH45 RG2D 1.25Gal 45° S
High Fire 10.0 144 3.0 1.0 12.45 72.7 249
Low fire 7.0 100 3.0 0.25 12.52 65.3 196
OUH60 RG2D 1.50Gal 45° S
High Fire 10.0 144 4.0 412.73 59.8 300
Low fire 7.0 100 4.0 0.7 12.16 52.8 232
Notes: CO2 values and Nett flue gas temperatures are given for guidance and measured values will depend on site conditions.
Riello Burner Settings - 28sec Oil - Kerosene - Net CV (Hi = 47.00MJ/kg)
1.2 Technical Data

page no. 10 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
1.3.1. Related Documents
All OUH heaters comply with the following European
Directives:
Energy Related Product Directive: 2009/125/EC*
Electromagnetic Compatibility Directive: 2004/108/EC
Low Voltage Directive: 2006/95/EC
Machinery Directive: 2006/42/EC
Air heater(s) must be installed in accordance with BS5410
Part 2, BS799 Part3 & part 5 and BS5440 plus any
relevant requirements of local and national building codes.
* where appropriate
1.3.2 Location
The location chosen for the air heater must permit the
provision of a satisfactory flue system and an adequate
air supply. The location must also facilitate ease of
servicing and satisfactory air circulation around the
heater.
The air heater must be installed strictly in accordance
with any fire regulations or insurance company's
requirements appertaining to the area in which the heater
is located, particularly where special risks are involved
such as areas where petrol vehicles are housed, cellulose
spraying areas, and wood working departments etc.
The air heater must be installed either:
1) OUH 20 models;-
(a) Suspended by chains or straps of adequate strength
to safely carry the weight of the unit and ancillary
equipment.
2) OUH 30/45/60 models:-
(a) Suspended from ’drop rods’ via purpose designed M10
suspension fixing points from the heater. Threaded drop
rods must have lock nuts fitted that are tightened down
onto the 10mm fixings in the heater.
(3) All OUH models:-
(a) in all cases, it is important that all supporting
structures have been assessed with regards to the
relevant weight loading.
(b) On specifically designed cantilever brackets from a
non-combustible wall or
(c) On a level non-combustible surface which is capable
of adequately supporting the weight of the air heater and
any ancillary equipment.
The heater must not be installed in conditions for
which it is not specifically designed e.g. highly corrosive
atmospheres, vitiated atmospheres, or where adverse
wind conditions may be experienced. Where the location
of the heater is such that it might suffer external
mechanical damage e.g. from overhead cranes, fork lift
trucks etc.
it must be suitably protected. Any ducting should be
kept as short and direct as possible having regard to the
distribution of the heated air and the max duct resistance
shown in section 1.3.10.
Any combustible material adjacent to the heater and
flue systems must be so placed as to ensure that its
temperature does not exceed 65°C (150°F).
1.3.3 Electrical Supply
Wiring external to the air heater must be installed in
accordance with the I.E.E. Regulations for Electrical
Installations and any local regulations which apply.
All standard heaters are supplied by 230V - 1ph, 50Hz.
The method of connection to the main electricity supply
must:-
- facilitate the complete electrical isolation of the unit(s)
via a suitable fused isolator (see section 2.4.5 for ratings)
- be in a readily accessible position adjacent to the unit(s)
- serve only the unit(s)
- have a contact separation of at least 3mm in all poles.
See the accompanying wiring diagram for the heater
electrical connections
OUH and fan/silencer units can also be supplied for 400V
3N, 50Hz.
1.3.4.1 Oil Supply
Powrmatic oil fired heaters are ONLY
designed for operation with either certified
Gas Oil to BS2869 Class A2 or D, (also
referred to as 35 sec Oil’ or ‘Red Diesel’) and
Kerosene to BS2869 Class C2, (also referred to as ‘28 sec
Oil’).
Powrmatic are not able to confirm the suitability of any
alternative blended Industrial Heating Oil (IHO) used to
fuel their appliances and as such will affect the warranty
on the appliance.
Construction and installation of service tanks and fittings
should be in accordance with: (a) BS 5410 Part 2 Section
6, (b) BS 799 Part 5 & (c) BS 1563. In addition the service
tank installation must comply with local regulations
and by-laws and with the requirements of insurance
companies
Refer to the detail provided in the burner handbook
regarding oil pipe sizing. These must be generally in
accordance with BS799 Part 3 and BS5410 Part 2.
Particular attention is drawn to the following:
1.3GeneralRequirements

page no. 11 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
a) Pipe jointing compounds must be capable of
withstanding the solvent action of the fuel oil under
all operating temperatures and pressures. Jointing
compounds containing oil shall not be used. Hemp and
other fibrous materials shall not be used as packing for
screwed joints.
b) Soft solder copper tube fittings and galvanised pipes
and fittings must not be used.
c) Oil lines must be completely air-tight.
d) The pump suction must not exceed a maximum of 0.4
bar (30cm Hg). Beyond this limit gas may be released
from the oil.
WARNING: The burners are supplied
adjusted for a single pipe system. If the
burner is to be used on a twin pipe system
the Internal bypass plug of the burner oil
pump must be fitted. Refer to the burner instruction
booklet.
Ideally the return pipe should terminate within the oil tank
at the same level as the suction line, both being below the
minimum oil level.
1.3.4.2 Fire Valve
It is recommended that the fire valves should be installed
as follows:
1. Main storage to service tank supply (if applicable)
2. Main storage to burner supply
3. Service tank to burner supply (if applicable)
Fire valves should be installed generally in accordance
with the requirements of BS799: Part 5. The fire valve
should be situated in an easily accessible position as near
the tank as possible and where practicable within the
boundary of the tank chamber or catchpit retaining wall).
1.3.5 Flue System
Only flue systems supplied through Powrmatic Ltd may
be used with OUH units. Several configurations of flue
and combustion air ducts are available.
The flue must terminate in a freely exposed position and
be sited to prevent the products of combustion entering
any opening in a building in such concentration as to be
prejudicial to health or a nuisance.
1.3.6 Ventilation Requirements
Type B flued installations.
Where LNVx heaters are installed within the heated
space (ie not in a plant room or an enclosure) and having
a building design air change rate of greater than 0.5/h,
additional provision for ventilation is not required.
If the building design air change rate is less than 0.5/h,
additional provision for natural or mechanical ventilation
is required. These being:
• Natural Ventilation:
Grilles having a free area of at least 2cm² per kW of rated
heat input shall be provided at low level i.e. below the level
of the heater flue connection.
• Mechanical Ventilation:
Must ensure that the space air change rate is at least
0.5/h, must be of the ‘input’ type and interlocked to
ensure the heaters cannot work if the input system is not
working.
Type B flued installations.
Where LNVx heaters are installed in a plant room or
an enclosure (i.e. not within the heated space) having
Type B23 Installation (these refer to section 2.3 of these instructions)
Air vents shall be permanently open.
Figures in column 1 are for heaters installed in the space they are heating.
Figures in column 2 are for heaters installed in a plant room, ventilation to outside air.
Figures in column 3 are for heaters installed in a enclosures, ventilation to outside air.
In all cases figures are per heater installed.
For multi heaters installations the appropriate values for each heater must be added together.
OUH Input
kW
In the heated
space
In a plant room, ventilation to
outside
In an enclosure, ventilation to
outside
Low level grille.
Free area cm²
Low level grille.
Free area
cm²
High level grille.
Free area cm² Low level grille. Free area cm² High level grille. Free area cm²
20 21.70 43.84 87.68 43.84 219.2 109.60
30 32.15 64.30 128.6 64.30 321.5 160.75
45 49.40 98.80 197.6 98.80 494.0 247.0 0
60 65.57 131.14 262.28 131.14 655.7 327.85
1.3GeneralRequirements

page no. 12 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
combustion air drawn directly from the room and
connected to a flue that evacuates the products of
combustion directly from the room additional provision
for natural or mechanical ventilation is required. These
being:
• Natural Ventilation:
There must be permanent air vents communicating
directly with the outside air, at high level and at low level.
Plant Rooms
Low level (inlet) 4cm²/kw of total rated net heat input
High level (outlet) 2cm²/kw of total rated net heat input
Enclosures
Low level (inlet) 10cm²/kw of total rated net heat input
High level (outlet) 5cm²/kw of total rated net heat input
• Mechanical Ventilation:
The minimum flow rate of ventilation shall be 4.14m³/h
per kilowatt of total rated heat input..
1.3.7. Air Distribution System
1.3.7.1.Freeblowing
Where single OUH units are required to cover a large floor
area, and in buildings with high roof or ceiling heights
Calecon thermal economiser units should be tted to
ensure even heat distribution and minimise stratication.
Care should be taken to avoid impeding the air throw with
racking, partitions, plant or machinery etc. Various outlet
congurations are available as optional extras to modify
the air throw pattern to suit particular site conditions.
1.3.7.2.Ductedunits
The CCF units are designed for use with duct work to more
precisely define the point of air delivery, and /or provide
ducted return air or ducted fresh air inlet.
IMPORTANT. Ductwork must comply with
current regulations and be correctly calculated
to comply with the maximum static resistance
available for the specific model installed (refer
to the duct resistance/ air volume tables shown opposite).
WARNING Ensure that the total aggregate
resistance¹ of the duct system, including any
dampers, grilles or filters etc, is equivalent to
the static pressure capability of the selected
heater.
If the total static resistance of the duct system is greater
than the stated for that heater, airflow will be restricted
and the heater may trip to overheat. Resistance must
be reduced to avoid nuisance temperature overheat
conditions.
Conversely if the duct system resistance is insufficient,
then the main fan motor may draw excess current and trip
to overload. Additional resistance must be introduced to
stop the fan motor from 'free-wheeling' and eventually
causing an electrical thermal trip condition. (e.g. by
adjustment of duct outlet nozzles and balancing of the
duct system).
Using a clamp meter around the fan power cable and with
all side panels closed, check the running current of the
centrifugal fan once the heater is running and compared
with the table shown in section 2.6.5.3.
Adjust the balancing dampers within the airflow ductwork
system to achieve the current suitable for that specific
model.
WARNING: DO NOT EXCEED THE STATED
MAXIMUM. Exceeding the MAX running
current will cause the fan’s thermal overload
to trip!
IMPORTANT. Furthermore, a 2000mm (2M)
straight plenum box with the same cross
sectional area as the heater outlet duct spigot,
must be fitted to outlet spigot prior to any
restriction² in ductwork.
WARNING: Failure to install this plenum box
could cause excess temperatures issues
with the heater and nuisance overheats.
All ducting must be independently supported of the air
heater. Joints and seams of supply ducts and fittings must
be securely fastened and made airtight.
It is recommended that ducting should be connected
to the heater spigots via an airtight flexible coupling of
noncombustible material. Before fitting coupling it must
be ensured that an adequate clearance will be maintained
between the ends of the ducting and the heater spigots.
All delivery and return air ducts, including air filters,
jointing and any insulation or lining must be constructed
entirely of materials which will not contribute to a fire,
are of adequate strength and dimensionally stable for the
maximum internal and external temperatures to which
they are to be exposed during commissioning and normal
operation.
Where inter-joist spaces are used as duct routes they
should be suitably lined with a fire-resisting material.
A full and unobstructed return air path to the air heater(s)
must be provided. If the air heater(s) is installed in a plant
room the return air intake(s) and the warm air outlet(s)
from the heater(s) must be fully ducted, into and out of the
plant room to avoid interference with the operation of the
1.3GeneralRequirements

page no. 13 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
IMPORTANT. It is essential that a
minimum 2000mm of straight ductwork,
with the same cross sectional area as the
heater outlet be connected to the heater
prior to any restriction.
OUH C Heater Unit
Airflow
Model Air Volume
(m³/h)
Max Duct
Resistance (Pa)
OUH20CCF 3600 275
OUH30CCF 2952 305
OUH45CCF 4284 275
OUH60CCF 6768 384
heater from other equipment.
The openings in the structure of the plant room through
which the ducting passes must be fire stopped. Care must
be taken to ensure that return-air intakes are kept clear
of sources of smells and fumes, and where there is any
possibility of pollution of the air by dust, shavings etc.,
precautions must be taken to prevent contamination.
If necessary suitable barrier rails should be provided to
prevent any combustible material being placed within
900mm of the outlets.
If required sound attenuators may be fitted in inlet and
outlet ducts to reduce airborne fan noise. Materials used in
outlet sound attenuators must be capable of withstanding
100°C air temperature without any deterioration.
¹ inlet ducting and outlet ducting. ² in respect to reducer, bend or
bi-directional section.
1.3GeneralRequirements

page no. 14 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
B
C
D
Distance from outside of heater to closest obstacle Distance
ARHS Clearance (when viewed at front of heater) mm 500
BLHS Clearance (when viewed at front of heater) mm 500
CTop of heater mm 1000
DRear of heater (dependent on flue system) mm 400
ERecommended mounting heights (floor level to underside of unit) OUH20/30F mm 2500-3000
OUH45/60F mm 3000-5000
For multi air heater installations the following minimum distances between units must be observed
Between units, side to side mm 3000
Between units, back to back mm 3000
E
Front View
R/H Side Views
D
B
2.1 Fitting the Unit

page no. 15 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
2.1 Fitting the Unit
2.1.1 Fitting space requirement
The air heater will be delivered to site pallet mounted and
protected by plastic sheeting.
Note: In order to achieve the desired
performance levels it is recommended that the
installation height (floor level to base of unit)
for OUH20 and OUH30 is between 2.5m and
3.0m, and OUH45 and OUH60 is between 3.0m and 5.0m.
Note: The minimum clearances must be
observed for installation and servicing.
Warning: Any combustible material adjacent
to the air heater and the flue system must
be so placed or shielded as to ensure that its
temperature does not exceed 65 °C.
Warning: When OUH modular components
are used in conjunction with the heater each
component must be individually supported.
If the heater is to be base mounted it may be stood
directly on the platform, provided it is of a suitable non-
combustible material and does not extend past the front
edge of the heater.
2.1.2 Suspending the heater
The air heater may be installed either:
a) Suspended by steel chains, rods or straps, dependent
on OUH model.
b) on specifically designed cantilever brackets from a non
combustible wall.
c) on a level noncombustible surface. The surface must
not extend past the front edge of OUH heaters.
The method of installation must be capable of adequately
supporting the weight of the unit (See section 1.2,) and
any ancillary equipment. Before installing the heater
the existing structure must be inspected to ensure it is
suitable. All supports should be protected against the
effects of rust or corrosion.
If noise levels are of particular importance, the heater
should be isolated from the structure of the building by
installing it on suitable anti-vibration mountings.
In all such cases, and in addition, when the heater is
suspended it is essential that all oil, duct, electrical and
flue connections to the heater are made with flexible
connections to maintain continuity of connection. In the
case of the flue connection single wall stainless steel flue
is deemed to flex sufficiently to meet the requirements.
Raise the heater up to the point of installation using
suitable and safe means and connect to the means of
suspension.
2.1.3 Air Distribution System
2.1.3.1 General
OUH/C and OUH/D models are designed for use with duct
work to more precisely define the point of air delivery,
and /or provide ducted return air or ducted fresh air inlet.
All ducting must be independently supported of the air
heater.
Joints and seams of supply ducts and fittings must be
securely fastened and made airtight. If required the
ductwork should be insulated to reduce heat loss.
2.1.3.2 Noise Reduction
Ducting should be connected to the heater spigots via
an airtight flexible coupling of non-combustible material.
Before fitting the coupling it must be ensured that a
minimum clearance of approximately 15mm will be
maintained between the ends of the ducting and the
heater spigots.
Sound attenuators may be fitted in inlet and outlet ducts
to reduce airborne fan noise. Materials used in outlet
sound attenuators must be capable of withstanding
100°C air temperature without any deterioration.
2.1.4 Room Thermostat Siting
The room thermostat should be fitted at a point which
will be generally representative of the heated area as
far as temperature is concerned. Draughty areas, areas
subjected to direct heat e.g. from the sun, and areas
where the air movement is relatively stagnant e.g. in
recesses, are all positions to be avoided.
The thermostat should be mounted about 1.5m from the
floor.
Any room thermostat, frost thermostat, time clock etc.
must be suitable for switching 230V, 5A and must be of
the 'snap action' type to minimise contact bounce.
For electrical connections of external controls see section
2.5 or the accompanying wiring diagram.
2.1.5. Oil Connections
The oil pipework length and diameter should be in
accordance with the information given in the burner
instruction booklet.

page no. 16 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
The pump suction should not exceed 0.4 bar.
The oil line must terminate not more than 450mm from
the burner with the final connection by the flexible hoses
supplied with the burner.
Because the burner is at high level it is recommended
that a non-return valve is fitted adjacent to the burner to
prevent oil draining back when the burner is not operating.
2.1.6. Electrical Connections
All units are fully prewired and only require final
connection of the incoming mains supply and completion
of the control circuit (230V) via a room thermostat, time
clock etc.
All units must be earthed. The electrical supply must
be run to a point adjacent to the heater and be suitably
terminated to provide an isolation point that will prevent
remote activation of the unit during servicing. See section
1.2 to ascertain the electrical loading of the unit(s) so
that cables of adequate cross-sectional area are used for
the electrical installation. The length of the conductors
between the cord anchorage and the terminals must be
such that the current carrying conductors become taut
before the earth conductor if the cable or cord slips out
of the cord anchorage. All external controls must be of an
approved type.
OUH/D models supplied less fan must be electrically
interlocked to the air movement system so that this is
started in the same manner as the air heater fan would
be viz. A connection from heater terminal 8 must be made
to one side of the fan motor contactor coil, the other side
of the coil being connected to Neutral. The fan motor
electrical supply must be direct and not taken from the
internal wiring of the OUH heater.
RIELLO BURNER
FLUE OUTLET
ELECTRICAL BOX
AXIAL FAN
FAN / LIMIT THERMOSTAT
HIGH LIMIT RESET
2.2GeneralIdentificationofItems
2.1 Fitting the Unit

page no. 17 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
2.3.1.GeneralRequirements
The minimum distance between surfaces of the flue pipe
and any surfaces made from combustible materials is
300mm. If it is necessary for the flue pipe to pass through
a structure made from combustible materials a metal
sleeve must be used so that the minimum clearance of
300mm is maintained.
2.3.2 Connection of Air Heater(s) to
FlueSystem
All models are supplied with a rear flue outlet.
The flue system connects directly into the flue socket on
the top (OUH20) or rear (OUH30 - 60) of the heater. The
socket is sized to accept standard sheet metal flue that is
secured in place using suitable fasteners.
The flue system must be fabricated with sockets facing
upwards and sound joints must be achieved by either:
(a) a close tolerance mechanical fit between sections, or
(b) the use of a suitable caulking string and cold caulking
compound.
In all cases the flue outlet socket must be connected via
an approved flue system to outside air.
The minimum flue length (end of flue terminal to top of
heater) shall not be less than 2.0m.
All flue ducts must be supported independently of the air
heater.
2.3.3. Installation of Flue System
A closed chimney system that conforms to the
requirements of EN1856-1 and has a designation
appropriate to the application must be connected to the
outlet of this tee. The cross sectional area of the chimney
serving the appliance must be not less than the area of
the flue outlet of the air heater.
The chimney must have a minimum height, from the
heater to the flue terminal, of 2m.
Horizontal runs of flue must be minimised but where they
are unavoidable the ratio of vertical to horizontal flue
should be not less than 3:1.
If necessary a single offset using two 45° bends can be
included to avoid obstructions. The minimum equivalent
resistance of the flue system should not be less than
0.0mb, the maximum not greater than 0.5mb.
In order to minimise condensation the use of twin wall
chimney is recommended. With high efficiency heaters
some condensation in the chimney, particularly at the
terminal, is unavoidable and in addition there can also be
rain water ingress.
Facilities should be made for disconnecting the chimney
pipe(s) from the air heater(s) for inspection and servicing
purposes.
The chimney outlet must be fitted with a terminal and
where the heater chimney is less than 200mm (8") in
diameter an approved terminal must be used.
The chimney must be supported independently of the air
heater.
The chimney must terminate in a freely exposed position
and must be situated so as to prevent the products of
combustion entering any opening in a building in such
concentration as to be prejudicial to health or a nuisance.
Note: For flue positioning and minimum
clearances of flue, please refer to current
IGE/UP/10, BS5440-1 and BS5440-2
standards.
2.3.4.CondenseDrainage
The design of the flue system should minimise the
formation of condensation and long external runs
should be completed in twin wall insulated flue. Where
condensate and/or rain water ingress is envisaged to be a
problem a flue drain length or condensate drain tee must
be fitted. The condensation pipe from the collection tray
to the disposal point should be of non-corrodible material
of not less than 22mm (3/4") size.
2.3 Fitting the Flue

page no. 18 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
2.4.1. Electrical Connections
Warning: THIS APPLIANCE MUST BE
EARTHED.
Warning: Wiring external to the unit must be
carried out by an appropriately qualified
person to current IEE regulations for
Electrical Installations and any local regulations which
apply.
The local electrical supply must be run to a point adjacent
to the heater and be suitably terminated to provide an
isolation point that will prevent remote activation of
the unit during servicing. Wiring should be completed in
flexible conduit.
The local electrical supply conditions must be compatible
with the electrical data given on the appliance data plate.
Heaters are for use with 230V, 1N, 50Hz supplies.
The method of connection to the main electricity supply
must:-
- facilitate the complete electrical isolation of the
heater(s) via a suitable fused isolator that will prevent
remote activation of the heater during servicing (see
section 2.4.5 for ratings).
- be in a readily accessible position adjacent to the
heater(s).
- serve only the heater(s).
- have a contact separation of at least 3mm in all poles.
See section 2.5 or the accompanying wiring diagram for
the heater electrical connections.
All units, (with the exception of units supplied with a
centrifugal fan/silencer duct section) are fully prewired
and only require final connections for the incoming mains
supply and completion of the control circuit (230V).
Reference must be made to Section 2.4.5 to ascertain
the electrical loading of the unit(s) being installed so that
cables of adequate cross-sectional area are used for
the electrical installation. The length of the conductors
between the cord anchorage and the terminals must be
such that the current carrying conductors become taut
before the earth conductor if the cable or cord slips out
of the cord anchorage. All external controls must be of an
approved type.
Models supplied with a centrifugal fan/silencer duct
section require wiring to be completed between the
heater and fan. Refer to supplied wiring diagram.
Warning: OUH D models supplied less fan
must be electrically interlocked to the air
movement system so that this is started in
the same manner as the air heater fan would be. Refer
to supplied wiring diagram.
Note: To achieve maximum system efficiency it
is recommended that LNVx units are controlled
by an MC200 or MC300 unit.
Simple room thermostat and thermostat/time clock
control systems will not provide optimum system
efficiency and fuel savings.
Wiring drawings and instructions are supplied with the
respective controller.
2.4.2. Initial Wiring Installation
Key:
Mains supply = 2 core and earth
MC200 Controller = 8 core and earth
alt. MC300 Controller = 6 core screened + LNE
Optional MC200 sensor = Screened 2 core*
* (screen must be grounded only at the MC200, See
instructions supplied with controller for wiring sizing,
Max. 100m)
Fused
Isolator
Controller
(MC200 shown)
Remote Sensor
(optional)
230V
Supply
Typical wiring
installation
2.4ElectricalCableInstallation

page no. 19 of 36
OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
2.4ElectricalCableInstallation
F - Free Blowing Unit CCF - Centrifugal Unit
Model Running
Current (A) Fuse/MCB Rating (A) Running Current (A) Fuse/MCB Rating (A)
(motor rated Protection Device)
OUH20 0.94 3 / 6 4.30 6 / 6
OUH30 0.46 3 / 6 4.33 6 / 6
OUH45 0.48 3 / 6 5.54 10 / 10
OUH60-35s 1.70 3 / 6 8.00 10 / 10
OUH60-28s 1.70 3 / 6 9.76 13 / 13
230V Heat Low Demand
230V Main Fan Only
230V Heat High Circuit
230V Lockout Indication
230V LNE to Controller
terminal 1
terminal 3
terminal 4 & 5
terminal 6
terminal 11, 12 & 13
L N
E
Output 230V Input 230V
Fan Only Signal 230V Heat On Signal 230V
Live Output Neutral Earth
t1 t3 t4 t5 t6 t10 t11 t
230V Supply
for Controller
High
Fire
Circuit
Lockout Signal 230V
2.4.3. External Wiring
The wiring terminals are located under the lid of the
electrical box on top of the unit.
Mains input 230V 50Hz 1Ph supply connections are via
a separate LNE terminal block. For input power refer to
table below. Control circuitry / external control mains
connections are via a numbered terminal strip. These
being:
2.4.4. Wiring Connections
2.4.5. External Fuses

page no. 20 of 36 OUH Range Users, Installation & Servicing Instructions Doc Ref M105 issue 5.8 Apr 2020.
Notes on both diagrams:
All signals are 230V AC 50Hz
Any controller or thermostat must receive its
supply from the heater terminals 10, 11 & 12
to ensure safe isolation during maintenance.
If a second stage thermostat is fitted for
High/Low operation, remove the link that is
fitted between terminals 4 & 5.
Warning: External controls
MUST be powered via heater
terminal 10, 11 and Earth
2.4ElectricalCableInstallation
2.4.6.1. Interconnecting Wiring OUH Installer Connections
2.4.6.2. Interconnecting Wiring OUH to Powrmatic MC200