WarmFlow WS18 User manual

Boiler Manual
Wood Pellet Boiler WS18/WP18
For use with ENplus A1 wood pellets only. Look for the ENplus A1 symbol.
Incorporating: User Instructions
Installation Instructions
Service Record
Guarantee Terms & Conditions
Registration Documents
LEAVE THIS MANUAL WITH THE END USER

IMPORTANT – Read this manual in full before installing, commissioning, servicing or
operating this appliance.
COMMISSIONING
This appliance must be commissioned. Failure to commission the appliance will invalidate the
warranty. After commissioning, ensure that the appliance registration documents are completed
and returned to Warmflow. See Section 7 of this manual.
SERVICING
To ensure continued reliable operation, fuel economy and to validate the guarantee, it is
recommended that the appliance is serviced annually or when indicated by the user control
interface. Servicing must be conducted by a Warmflow engineer or other trained and competent
engineer. A service history must be maintained in Section 8 of this manual.
NI Customers Only
Warmflow Engineering customer care (NI) provides an excellent back-up service, operating a
team of trained engineers who can meet all the servicing, commissioning and breakdown
requirements for your appliance.
Tel: [phone]
Fax: [phone]
E-mail: [email protected]
Web: www.warmflow.co.uk
For Parts, Service, Technical & Warranty Contact
Great Britain & N. Ireland, Tel: [phone]
Republic of Ireland, Tel: [phone]
LISBURN TELFORD
Lissue Industrial Estate, Moira Road, Unit D1, Hortonpark,
Lisburn, Co. Antrim, N. Ireland, BT28 2RF Hortonwood 7, Telford, TF1 7GX
Tel: [phone] Tel: [phone]
Fax: [phone] Fax: [phone]
E-mail: [email protected] E-mail: [email protected]k
[email protected] [email protected]
[email protected] [email protected]

CONTENTS
1 KEY INFORMATION.............................................................................................................1
1.1 The Clean Air Act 1993 and Smoke Control Areas.....................................................................4
2 USER INSTRUCTIONS.........................................................................................................5
2.1 Filling the Pellet Hopper .............................................................................................................5
2.2 System Pressure........................................................................................................................6
2.3 System Filling.............................................................................................................................6
2.4 User Control Interface................................................................................................................7
2.4.1 Home Screen Icons and their meaning. ...............................................................................................8
2.4.2 Using the Main Menu............................................................................................................................9
2.5 Cleaning...................................................................................................................................19
2.5.1 Cleaning Scheduler.............................................................................................................................19
2.5.2 Cleaning Status...................................................................................................................................20
2.5.3 Cleaning Procedure............................................................................................................................23
3 INSTALLATION REQUIREMENTS ....................................................................................36
3.1 General Requirements.............................................................................................................36
3.1.1 Transportation aids and hearth...........................................................................................................36
3.1.2 Service Access ...................................................................................................................................37
3.1.3 Heating System...................................................................................................................................37
3.1.4 Air Vents .............................................................................................................................................37
3.1.5 Drain Cock ..........................................................................................................................................38
3.1.6 Pipework .............................................................................................................................................38
3.1.7 Heating System Design ......................................................................................................................38
3.2 Sealed Systems.......................................................................................................................38
3.2.1 Expansion Vessel (WS 18 Models only).............................................................................................38
3.2.2 System Filling......................................................................................................................................39
3.2.3 System Pressure (WS 18 only)...........................................................................................................39
3.2.4 Pressure Relief Valve .........................................................................................................................39
3.2.5 Low Pressure Switch ..........................................................................................................................39
3.2.6 Condensate Trap................................................................................................................................39
3.3 Wiring Layout...........................................................................................................................42
3.4 Flue System.............................................................................................................................44
4 COMMISSIONING AND SERVICING.................................................................................46
4.1 Commissioning – Approximate time to complete: 2 hours ........................................................46
4.2 Servicing..................................................................................................................................55
4.2.1 Service Schedule................................................................................................................................55
5 ALARMS AND TROUBLESHOOTING...............................................................................56
5.1 Alarms......................................................................................................................................56
5.2 Troubleshooting .......................................................................................................................63
6 YOUR GUARANTEES, TERMS & CONDITIONS...............................................................65

7 APPLIANCE INSTALLATION/COMMISSIONING CERTIFICATE & REGISTRATION......69
8 APPLIANCE SERVICE RECORDS....................................................................................72
9 APPENDIX A – SUPPLEMENTARY INSTALLATION AND OPERATING INSTRUCTIONS
FOR THE UK MARKET.............................................................................................................83
10 APPENDIX B – CUSTOMER CONNECTION WIRING SCHEMATIC .............................91

1
1 KEY INFORMATION
The appliance is rated to IP45 and has a weather-proof housing suitable for both internal and
external installation.
The appliance is supplied with a flue terminal which may need to be extended or adapted
depending on the installation situation. Extension pieces, bends and bracketry can be
purchased from Warmflow stockists. The appliance is also fitted with a flue draught stabiliser.
The wood pellet fuel is loaded into the integrated hopper located at the rear of the appliance
(see Figure 1 above). The hopper door must be kept closed at all times when not refilling. An
interlock switch is fitted to the hopper door meaning the appliance will not operate if the hopper
door has been left open.
The service access lid is located on top of the appliance and should only be removed once
power has been isolated using the isolator switch. The service lid and side panels give access
for plumbing, servicing and maintenance.
The combustion door is located behind the green coloured front casing door and has an
interlock fitted to ensure the door cannot be opened during firing of the appliance.
Knockouts in the casing are provided at a number of locations to aid the plumbing installation.
The installer wiring panel is located behind the green coloured front casing door.
Figure 1: Wood Pellet Boiler Overview.

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Once removed the service lid gives access to the heat exchanger for servicing and routine
maintenance as shown in Figure 2. To clean the internal surfaces of the heat exchanger,
remove the main HE inspection door and the HE cleaning mechanism door. Caution: never
attempt to remove the doors after the appliance has just finished operating as surfaces
will be extremely hot and injury will result.
The combustion pot is located on the inside of the combustion door and can be removed for
servicing and routine maintenance by releasing the toggle latches on either side of the pot as
shown in Figure 3. Once the toggle latches are released the pot will be free to lift vertically from
the combustion shelf. Caution: never attempt to remove the pot after the appliance has
just finished operating as it will be extremely hot and injury will result.
Figure 2 - Service Access. (Service Lid and Insulation Removed)
Figure 3: Combustion Door and Ash Pan Assembly.

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The ash level in the ash pan should be checked periodically. The ash pan must never be
permitted to over fill. Under normal operating conditions during the heating season the ash pan
will typically require emptying on a monthly basis. The appliance should never be operated
without the ash pan in position. The ash may be discarded with garden waste or in line with
local waste disposal regulations, after first ensuring that it is sufficiently cool before emptying
the pan. Caution: never attempt to remove the ash pan after the appliance has just
finished operating as it will be extremely hot and injury will result.
The combustion pot should be cleaned on a weekly basis removing any carbon residue.
Vacuuming with a dedicated ash vacuum cleaner is recommended. Failure to clean the
combustion pot as directed may restrict the flow of air within the appliance adversely affecting
its performance.
Description Model WS18/WP18
Type Wood Pellet Boiler
Dimensions (mm) Width 650
Depth 1170
Height 1135
Dry Weight (kg) 250
Minimum Allowable Draft (mbar) 0.04
Flue Pipe Diameter (mm) 80
Exhaust gas temperature at maximum output (⁰C) 170
Exhaust gas temperature at minimum output (⁰C) 65
Exhaust gas mass flow at maximum output (⁰C) 0.015
Exhaust gas mass flow at maximum output (⁰C) 0.005
Electrical Supply 230V Single Phase @50Hz
Maximum Current (Amps) 5
Maximum Wattage 420
Standby Wattage 20
Performance/Efficiency
(kW)/(%) Maximum Output 18/92.9
Minimum Output 4/90.1
Fuel Type Wood Pellets
Quality ENPlus A1
Maximum Allowable Pressure (bar) 3
Maximum Allowable Flow Temperature (⁰C) 80
Water-side resistance ∆t 10k (mbar) 9
Water-side resistance ∆t 20k (mbar) 4.2
Water Capacity (Litres) 60
Fuel Hopper Capacity (kg) 120
Boiler Class Efficiency 5
Emissions 5
Combustion Ventilation
@20⁰C for internal Installation Low Level (mm x mm) 250 x 250
High Level (mm x mm) 250 x 250
Table 1: Product Data

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1.1 The Clean Air Act 1993 and Smoke Control Areas
Both appliances, the WS18 and WP18 comply with the requirements of the Clean Air Act 1993
and are suitable for installation in smoke control areas. The appliances meet the emissions
limits for particulate matter and NOxas stated by DEFRA. As such the emissions are within the
acceptable limit for the appliances to be used in installations wishing to claim the renewable
heat incentive.
Your local authority is responsible for implementing the Clean Air Act 1993 including
designation and supervision of smoke control areas and you can contact them for details of
Clean Air Act requirements.

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2 USER INSTRUCTIONS
2.1 Filling the Pellet Hopper
The wood pellets used to fuel the appliance must be compliant with the ENPlus A1 pellet
standard. Using alternative pellets will invalidate the product warranty.
It should be also noted that the Warmflow wood pellet boiler appliance is suitable for use
in smoke control areas when burning ENPlus A1 pellets only.
The key parameters for ENPlus A1 pellets are found in Table 2 below.
Property Unit Value
Net Calorific Value Q MJ/Kg 16.5≤Q ≤19
Diameter mm 6
Length mm 3.15 to 40
Moisture Content % ≤10
Ash Content % ≤0.7
Mechanical Durability % ≥97.5
Fines % ≤1.0
Chlorine Content % ≤0.02
Sulphur Content % ≤0.03
Nitrogen Content % ≤0.3
Table 2: Threshold Parameters for ENplus A Wood Pellets According to EN ISO 14961-2
The fuel hopper has a wood pellet capacity of 120kg. At maximum output the appliance will run
for approximately 30 hours before requiring refilling. Therefore, the fuel hopper will typically
require filling on a weekly basis during the heating season. Care must be taken to avoid
exposure of wood pellets to rain or other moisture during storage or filling. To protect the user a
hopper safety guard is located in the top of the hopper beneath the fuel hopper door. This must
not be removed.
The wood pellet fuel must be stored in a cool dry area away from sources of ignition,
condensation, excess humidity or other sources of moisture. Whether stored in bags or in bulk it
is important that care is taken to handle the wood pellets in such a way that ensures they won’t
deteriorate and create dust.
The Warmflow wood pellet boiler appliance automatically delivers the correct amount of fuel
from the hopper to the combustion chamber using its integral auger.

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2.2 System Pressure
When the appliance is connected to a sealed central heating system, the system pressure
should be checked periodically by means of the pressure gauge at the expansion vessel (see
Figure 4). The WS18 appliance comes complete with an integrated expansion vessel, pressure
gauge and filling loop. The minimum pressure, as indicated by the black needle, must not be
less than 0.5 bar when the appliance is cold and typically around 2.5 bar when the appliance is
at normal operating temperature. If the pressure is outside this range contact Warmflow or your
installer.
System Pressure = 0bar System Pressure = 1bar
2.3 System Filling
After the system has been properly filled the pressure gauge should read 1 bar when the
system is cold (refer to the image on the right in Figure 4). The valve must be fully closed and
the flexible filling loop removed from the valve in accordance with building regulations. Expect a
small water loss from the pipe.
At filling or re-filling of the system, special attention must be given to the concentration of
corrosion inhibitors in the system water. Where there is a need for topping up, concentrations
must be restored to inhibitor manufacturers’ recommendations and monitored going forward.
Frequent or routine topping up of the system should not be necessary and may prove harmful to
the appliance. Should topping up prove necessary on a frequent or routine basis you must
contact Warmflow or your installer.
For further information refer to Section 3.2 Sealed Systems (see page 38).
Figure 4: Reading System Pressure.

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2.4 User Control Interface
The appliance’s user control interface (see Figure 5) has been designed to maximise the ease
of use and efficiency of the heating system.
All user interactions with the appliance are via the display panel. Hence the display panel
should be mounted at an easily accessible location. The user control interface provides access
to appliance parameters such as temperatures, cleaning alerts, servicing and pellet level
indicators together with commissioning and service settings.
Display active alarms
Select main menu
Previous menu
Select UP
Select DOWN
Enter / select
Figure 5: User Interface Display and Function Keys.

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2.4.1 Home Screen Icons and their meaning.
The home screen appears as shown in Figure 6.
Boiler Status
Icon Status Meaning
Boiler OK The appliance is functioning normally. There are no faults or alerts. Servicing is not due.
Boiler Alert
The appliance has reached alert condition but will continue to operate as normal. This alert
means that servicing is now due. The servicing time limit can be seen by pressing the
‘Display active alarms’ key. You should arrange servicing as soon as possible and before
servicing is overdue otherwise the appliance will shut down.
Boiler Fault The appliance has shut down due to a fault or alert. This may be a fault with the appliance,
an overdue service/clean or an empty hopper.
Fuel Status
Icon Status Meaning
Fuel Level
OK The pellet level in the hopper is fine. There are no faults or alerts.
Fuel Level
Low
The pellet level in the hopper is low. The appliance will typically run as normal for 1 hour
dependent on the heat demand of the property. You should fill the hopper within this time.
Filling the hopper will automatically reset this alert.
Fuel Level
Empty The pellet hopper is now empty. The appliance will shut down. You should fill the hopper immediately. Filling the hopper will automatically reset this alert.
Cleaning Status
Icon Status Meaning
Cleaning
not required The appliance is functioning normally. There are no faults or alerts. Cleaning is not due.
Cleaning
Due
This alert means the appliance is due for cleaning. The cleaning time limit can be seen by
pressing the display active alarms button. You should clean the appliance as soon as
possible and before cleaning is overdue otherwise the appliance will shut down.
Cleaning
Overdue
Cleaning is now overdue. The appliance will shut down. You should clean the appliance
immediately. Cleaning the appliance will automatically reset this alert and reset the
countdown timer.
Figure 6: Icon Descriptions.
Fuel Status
Boiler Status
Current Page
Cleaning Status

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2.4.2 Using the Main Menu
The main menu can be accessed by pressing once on the ‘Program key’. This displays the
main menu as shown in the Figures 7 and 8 below.
The ‘Down Arrow’ or the ‘Up Arrow’ key can then be used to scroll through the menu.
Confirm selection with the ‘Enter key’ when the required item is highlighted in black. There
are six options in the main menu including ‘Home’, ‘Alarms’, ‘Cleaning’, ‘Engineer’, ‘Settings’
and ‘Help’.
Home:
Selecting the home menu returns the display to the home screen. This display is as shown in
Figure 9 and detailed in section 2.4.1.
Figure 7: Main Menu Page 1.
Figure 9: Home Screen.
Figure 8: Main Menu Page 2.

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Alarms:
Selecting the alarms menu enters the alarms display. This can also be entered at any time by
pressing the ‘Display active alarms’ key. The screen shown in Figure 10 will be displayed
when no alarms are present.
When an alarm is present, the ‘Display active alarms’ key will flash red. Pressing the
flashing key or entering the alarm menu will then display one or more active alarms or faults.
The ‘Down Arrow’ or the ‘Up Arrow’ key can then be used to scroll through the alarms.
Refer to Section 5 for more information on the alarm messages that can be displayed and the
appropriate action to take in each case.
Cleaning:
Selecting the cleaning menu option enters the cleaning status display. A typical example of a
cleaning status is shown in Figure 11.
When viewing the cleaning status display, press the ‘Enter’ key to proceed to cleaning the
appliance. The full cleaning procedure detailing the necessary steps to correctly clean the
appliance can be found in Section 2.5.3.
Figure 10: Alarms Screen.
Figure 11: Cleaning Status

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Settings:
Selecting the settings menu enters a sub-menu which has a number of information and setting
screens. These can be viewed and adjusted by the user. The information and setting screens
are displayed in the same format as the main menu screen and may be accessed in the same
way. The sub-menus include date/time, temperature and information as shown in Figure 12
below.
Date / Time:
Selecting the date/time sub-menu enters the appliance clock and date management system. It
is very important that the date and time are set correctly as shown in Figure 13.
The date and time are adjusted using the ‘Down Arrow’ or the ‘Up Arrow’ keys. Confirm
with the ‘Enter key’. The day will automatically update when the date is altered.
Temperature:
Selecting the temperature sub-menu enters the screen from which the appliances flow
temperature may be adjusted. The flow temperature is the temperature at which the heating
system water which leaves the appliance and enters the central heating circuit. This can be
adjusted between 60°C and 80°C. The temperature is adjusted using the ‘Down Arrow’ or the
‘Up Arrow’ keys. Confirm with the ‘Enter key’ as shown in Figure 14.
Figure 12: Settings Menu.
Figure 13: Date/Time Home Screen.
Figure 14: Temperature Screen.

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Information:
Selecting the information sub-menu allows 3 information screens to be viewed. The first two
information screens display a list of values relating to the operational performance of the
appliance as shown in Figures 15 and 16. These values are for monitoring purposes only and
cannot be altered. A description of the information displayed in Figures 15 and 16 is given in
Tables 3 and 4 respectively, along with expected values that are considered normal.
Text Description Expected Value(s)
Clock on Indicates whether a switched live signal is
being received by the appliance in order to
operate. Usually from an independent time
clock or room thermostat.
“No” – Means there is no switched live signal. The
appliance will not operate unless Freeeze Risk
Mode is enabled. (See Table 6)
“Yes” – Means there is a switched live signal. The
appliance will operate, unless it is already up to
temperature or has an active alarm.
Flue Temp. The temperature of the flue gases leaving the
appliance displayed in degrees Celsius. Ambient temperature if the appliance is cold.
No greater than 170⁰C in normal operation.
Flow Temp. The temperature of the water in the flow pipe
connected to the top of the heat exchanger,
displayed in degrees Celsius.
Ambient temperature if the appliance is cold.
No greater than 85⁰C in normal operation.
Return Temp. The temperature of the water in the return
pipe connected to the bottom of the heat
exchanger, displayed in degrees Celsius.
Ambient temperature if the appliance is cold.
No greater than 80⁰C in normal operation.
Mode Indicates the operating mode of the
appliance. The operating mode changes
through start-up, operation and shut down.
(Refer to Table 5)
Standby, System Check, Pre-load, Ignition,
Stabilisation, Powerband 1,2,3,4,5, Extinguish,
Final Clean, Blocked.
Time Indicates how long the appliance has been
operating in the mode displayed above.
Displayed in hours, minutes and seconds.
The OK status displayed beside the time can
change. (Refer to Table 6)
Any value is possible up to 99h 59m 59s
Resets to 0h 0m 0s every time the operating
mode changes.
Lux Indicates the level of light in the heat
exchanger of the appliance and is therefore
an indication of how well the flame is
developed in the heat exchanger.
0 Lux = No flame
5000 Lux = Very well developed flame
0 – 5 Lux in Standby and System Check modes
0 – 500 Lux in Pre-load and Ignition modes
150 – 1500 Lux in Stabilisation mode
150 – 5000 Lux in Powerbands 1,2,3,4,5
35 – 5000 Lux in Extinguish mode
0 – 35 Lux in Final Clean and Blocked modes
Table 3: Description of Information Screen 1
Figure 15: Information Screen (1 of 3).

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Text Description Expected Value(s)
Valve Pos. Indicates the position of the anti-
condensation valve in the appliance.
0% = Valve fully opened = all heat to property
100% = Valve closed = water circulation in
the heat exchanger (HE) only to raise the HE
temperature and avoid condensation.
50% in Standby Mode.
Modulates between 0 - 100% in all other modes.
Pump Speed Indicates the speed of the circulating pump in
the appliance. Modulates during operation
depending on the Heat Req.
0% in Standby Mode.
Modulates between 0 – 100% in all other modes.
Heat Req. Indicates the heat demand of the property.
Calculated using the Flow Temp. and Return
Temp. which are continuously monitored by
the control system of the appliance.
Varies between 0% and 100%. Heat Req. will
tend towards 100%. if the heat demand of the
property is high i.e. the property is cold. As the
temperature of the property increases, the Heat
Req. value will decrease.
Draught Set Indicates the draught required for good
combustion, displayed in Pascals (Pa). This
value is determined by the operating mode
and feedback from the Lambda sensor that
continually monitors oxygen content of
combustion gases.
0Pa in Standby Mode
35Pa in System Check, Pre-load, Ignition modes
40Pa in Stabilisation mode
15 – 105Pa in Powerbands 1,2,3,4,5
80Pa in Extinguish mode
0Pa in Final Clean and Blocked Mode
Draught Act Indicates the actual draught achieved
through the appliance by the exhaust fan,
displayed in Pascals (Pa).
Should match “Draught Set” values ± 10%
Fan Speed Indicates the speed of the exhaust fan. A
continuous fan speed of 100% means the
exhaust fan is working at maximum capacity
to achieve the Draught Set value. If the fan
speed is 100% and the Draught Act. is lower
than the Draught Set, the appliance may
need to be cleaned or serviced.
Usually between 50% and 100%.
Table 4: Description of Information Screen 2
Figure 16: Information Screen (2 of 3).

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Information screen 3 displays a list of values relating to the software used in the appliance as
shown in Figure 17. The most important of these values is the Software Ver. (meaning software
version). The example in Figure 17 displays the Software Ver. as 3.106b. It is beneficial to be
aware of the software version used on the appliance prior to seeking technical support.
The operating mode of the appliance varies through start-up, operation and shut down, and can
be seen changing when viewing information screen 1 (see Figure 15). Further explanation of
each operating mode is given in Table 5.
Mode Description
Standby Awaiting heat demand
System Check Ensuring that the appliance is ready and safe to start
Pre-Load Loading the combustion pot with pellets
Ignition Igniting the combustion pot with pellets
Stabilisation Ensuring that the flame is given time to establish
Powerband
1,2,3,4,5 Output power determined by heat demand
Extinguish Shut down initiated
Final Clean Cleaning of combustion pot and heat exchanger
Blocked Anti-cycling function that activates a time delay before a restart is possible or the combustion door
can be opened
Table 5: Appliance Operating Modes.
Figure 17: Information Screen (3 of 3).

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The appliance has a start-up sequence as shown in Figure 18 (see page 16) and will only begin
firing if there is a heat demand present, i.e. a signal from a time clock or programmer, or if
Freeze Risk Mode is enabled (See table 6). As the appliance is fully modulating the control
system will monitor the heat demand and work to meet the demand as efficiently as possible.
Once the heat demand has been met the appliance will modulate down through its power bands
and may eventually enter extinguish mode.
If extinguish mode is reached and after final clean, the appliance will enter blocked mode. The
appliance will remain in blocked mode for a period which is pre-set in order to stop the
appliance cycling which is inefficient.

16
Figure 18: Flow Chart.