Grant Spira Series, Spira 5-18, Spira 6-26, Spira 9-36 User, Installation And Servicing Instructions

Grant Spira

5-18kW, 6-26kW and 9-36kW Condensing Wood
Pellet Boiler

User, Installation and Servicing Instructions

UK | DOC 0042 | Rev 2.0 | October 2015

Important Note

Important Note for Installers

After installing the boiler leave these instructions with the appliance.
This appliance is deemed a controlled service and specific regional statutory requirements may be applicable.

GRANT ENGINEERING (UK) LIMITED

Hopton House, Hopton Industrial Estate, Devizes
Wiltshire SN10 2EU

Tel: [phone] Fax: [phone]
Email: [e-mail] www.grantuk.com

This manual is accurate at the date of printing but will be superseded and should be disregarded if specifications and/or appearances are
changed in the interests of continued product improvement.
All good sold are subject to our official Conditions of Sale, a copy of which may be obtained on application.

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© Grant Engineering (UK) Limited 2015. No part of this manual may be reproduced by any means without prior written consent.

User Instructions - contents

For the Installation and Servicing Instructions, please refer to page 20.

1 Introduction 4

2 About your Boiler 4

2.1 General 4

2.2 Pellet Hoppers 4

2.3 Bulk Pellet Stores 4

2.4 Boiler Operation 5

2.5 Cleaning 5

3 About your Fuel 5

4 Boiler Controls 7

4.1 Boiler Control Panel 7

5 Burner Control Panel 8

5.1 Burner Control Panel 8

5.2 Error Messages 9

5.3 Service Indicator 9

5.4 Active Symbols 9

6 Pellet Feed Thermostat 10

7 Priming the Auger 10

8 Lighting the Boiler 11

9 If you Boiler Fails to Light 12

10 Emptying the Ash Pan 14

11 Cleaning and Servicing your Boiler 16

12 Ventilation 16

13 Electricity Supply 16

14 Sealed Central Heating system 16

15 Frost Protection 17

16 Corrosion and Protection 17

17 Service Log 18

This appliance can be used by children aged from 8 years and above and persons with
reduced physical, sensory or mental capabilities or lack of experience and knowledge if they
have been given supervision or instruction concerning use of the appliance in a safe way and
understand the hazards involved. Children shall not play with the appliance. Cleaning and user
maintenance shall not be made by children without supervision.

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1 Introduction

This guide is intended to assist and instruct the user in the operation of the Grant Spira Condensing Wood Pellet Boiler.

A separate manual is available to the installer for the installation, servicing and commissioning of the boiler.

The following special text formats are used in this manual for the purposes listed below:

WARNING

Warning of possible human injury as a consequence of not following the instructions in the ‘Warning’.

CAUTION

Caution concerning likely damage to equipment or tools as a consequence of not following the instructions in the ‘Caution’.

NOTE

Note text. Used for emphasis or information not directly concerned with the surrounding text but of importance to the reader.

2 About your Boiler

2.1 General

Your Grant Spira wood pellet boiler should only be installed, commissioned and serviced by a Grant Accredited Installer who has
undergone specific product training by Grant Engineering (UK) Ltd.

If you have a Grant Spira 5-18, 6-26 or 9-36, your boiler basically consists of two parts:

• The boiler itself, with the burner mounted on the front

• The pellet hopper, with the pellet feed auger protruding from the front of the hopper casing

The hopper may be either a 110kg or 200kg capacity unit and will be located on either the left or right hand side of the boiler.

Check with your installer for the actual capacity of pellet hopper you have with your boiler.

Alternatively, if you have a Grant Spira 11-44, 12-52, 15-62 or 18-72, your boiler will basically consist of three par ts:

• Two boilers, each with the burner mounted on the front

• The pellet hopper, with two pellet feed augers protruding from the front of the hopper casing

In this case the hopper will have a 140kg capacity and will be located between the two boilers.

CAUTION
All Grant Spira boilers and pellet hoppers are designed for indoor use only and MUST be positioned in a dry environment.

2.2 Pellet Hoppers

The pellet hopper is mounted on castors (with the front castors lockable) to allow it to be easily moved when required. Allow sufficient
area in front of the hopper for it to be moved out and away from the boiler(s) for servicing.

The electrical connections to the boiler(s) are all made to the 4-way electrical plug on one of the three factor y-fitted ‘flying leads’ at the
rear of the pellet hopper.

All Grant pellet hoppers are fitted with a contents switch. Refer to Figure 2-1.

This automatically detects when the level of pellets in the hopper falls to a pre-set
minimum value.

The minimum quantity of pellets required to restart the boiler is 20kg for the single boiler
hoppers and 30kg for the double boiler hoppers.

If you have a bulk pellet store (refer to Section 2.3), the contents switch automatically
triggers the operation of either the bulk store auger or Grant SpiraVAC system, whichever
is fitted, to deliver pellets from the bulk pellet store into the pellet hopper beside the boiler.

When there is no bulk store (but the pellet hopper only), the contents switch stops the
burner operating when the minimum pellet level is reached. In this case, topping up the
hopper with more pellets will automatically operate the contents switch and the burner will
restart, as long as there is a demand from the heating controls (room thermostat, etc.) for
the boiler to run.

CAUTION

Always ensure that the door on the top of the pellet hopper is closed after filling to ensure no foreign debris enters the hopper. The
hopper should only be filled to the point where it is still possible to close the top door.

Figure 2-1: Contents switch in the base of the
pellet hopper

2.3 Bulk Pellet Stores

You may also have a bulk pellet store, located either inside or outside the building. If so, check with you installer for the capacity of the
bulk pellet store.

If you have a bulk pellet store you will have either a bulk store auger, or a Grant SpiraVAC vacuum system, to move the pellets from the
bulk store to the pellet hopper as and when required. Check with your installer regarding which system you have fitted. If you have the
Grant SpiraVAC system, please refer to the instructions provided with that system for details of its operation.

NOTE
If you have a bulk pellet store it is essential that you routinely check the level of pellets in the store and arrange for a
delivery of pellets before the store is empty.

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Where a bulk store is fitted; if the bulk store and pellet hopper are both allowed to run out of pellets then the error message ‘FAILED

PELLET LIGHTING’ will be displayed on the burner control panel screen. Once the bulk store has been refilled with pellets, the bulk
store auger (if fitted) will need to be re-primed before the pellet hopper is automatically filled from the bulk store.

If a Grant SpiraVAC vacuum system is fitted refer to the Instructions supplied with the system to restart the pellet supply to the pellet
hopper.

Once the pellet hopper is filled, the pellet hopper auger will also need to be re-primed. Refer to Section 7 of these instructions.

Once this has been done press the reset button on the burner control panel to cancel the error message and restart the boiler.

2.4 Boiler Operation

During the combustion process, hydrogen and oxygen combine to produce heat and water vapour. The water vapour produced is in
the form of superheated steam that contains heat that is locked up in the flue gases. A conventional boiler cannot recover any of this
heat and this energy is lost to the atmosphere through the flue.

Your Grant Spira condensing wood pellet boiler contains an extra (secondary) heat exchanger which is designed to recover much of the
heat normally lost by a conventional boiler through the flue system. It does this by cooling the flue gases and extracting more heat from
them, pre-heating the cooler water returning to the boiler from your heating system.

Even when not operating in a condensing mode, this additional heat exchanger ensures that your Grant Spira boiler will still operate at
an extremely high efficiency.

The burner output is determined by the delivery rate of the pellets via the pellet feed auger (on the pellet hopper). This is automatically
controlled by the burner control system. During commissioning the burner control parameters should have been checked and adjusted
as necessary by your Installer.

WARNING
Do not adjust or modify the appliance in any way as to do so could cause malfunction of the appliance, injury to persons or
death or result in a potential fire hazard.

Only an Grant trained installer, who has completed the Grant training course, should carry out any work on the appliance.

Once commissioned by a Grant trained installer, your Grant Spira boiler will operate automatically to provide heating and domestic hot
water (if you have a hot water cylinder fitted), as long as:

• There are sufficient pellets of the correct type in the pellet hopper. Refer to Section 3.

• The pellet auger is fully primed. Refer to Section 7.

• The heating system controls are set to ON and ‘calling’, i.e. the programmer and room thermostat are on.

• The burner ON/STANDBY switch on the boiler control panel is set to ON. Refer to Section 4.

If your appliance is controlled by a remote programmer and/or a room thermostat, it will provide heating and (when fitted) hot water
during the ON periods as set on the programmer, when either the room thermostat and/ or the hot water cylinder thermostat are
‘calling’.

WARNING
Always ensure the front access door of the combustion chamber is fully closed and latched during operation.

Certain external surfaces of the boiler will be hot to touch when in operation, due care is needed.

2.5 Cleaning

The burner incorporates a brazier, located within the boiler combustion chamber, where the combustion of the wood pellets takes
place. This brazier is fitted with a self-cleaning system to prevent a build-up of ash and clinker. This operates automatically after a pre­set period has elapsed.

The boiler has two heat exchangers, the primary and secondary (condensing), and each is fitted with a self-cleaning system to keep the
heat exchanger tubes clear of ash build-up. As with the brazier cleaning system, these are operated automatically after a pre-set period
has elapsed.

CAUTION

Even with the automatic cleaning systems, it is vitally important that the boiler ash pan is regularly emptied and the boiler regularly
serviced. Refer to Sections 10 and 11 of these instructions for further information on the cleaning and servicing of your boiler.

3 About your Fuel

You Grant Spira boiler is designed to run only on 6mm diameter EN Plus Grade A1 wood pellets (conforming to EN14961-2).

Under no circumstances should any other form of biomass fuel be used with this boiler.

WARNING
ONLY EN Plus Grade A1 (EN14961-2) wood pellets MUST be used with your Grant Spira boiler. These pellets must be bark
and sand free AND previously tested by Grant BEFORE being used in your Spira boiler.

Failure to use pellets that meet the conditions above will invalidate the product guarantee. If you are in any doubt over
which pellets are suitable please contact Grant for assistance.

For your guidance, below are examples of both the correct grade of pellets to be used and poor quality pellets that must
not be used in your Grant Spira boiler.

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Figure 3-1: Correct grade of pellets

Figure 3-2: Poor quality pellets

Meets EN Plus Grade A1.

Correct diameter and length with no dust and minimum bark content.

Pellets not pressed correctly causing them to easily disintegrate.

DO NOT USE!

The auger will be unable to consistently deliver these pellets from the
hopper to the burner, resulting in pellet lighting problems.

Too much bark content.

DO NOT USE!

These will cause excessive sand in the ash resulting in clinker blocking
air holes, poor combustion and jamming of the brazier cleaning system.

Figure 3-3: Pellets too dark in colour

Figure 3-4: Pellets too short in length

Figure 3-5: Pellets with high dust content

DO NOT USE!

The auger will not be able deliver these pellets at the correct rate to the
burner, affecting the input (and output) of the boiler and the combustion.

DO NOT USE!

The auger will not be able deliver these pellets from the hopper to the
burner, resulting in pellet lighting problems.

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4 Boiler Controls

Figure 4-1:Boiler Control Panel

4.1 Boiler Control Panel

The boiler control panel is located at the top of the boiler. This control panel is fitted with three controls, as follows:

• BURNER ON/STANDBY switch:

To switch off the burner when required, by interrupting the signal from the heating system controls, i.e. the remote programmer and
room thermostat.

This switch MUST be left in the ON position during normal operation of the boiler.

WARNING
This switch does NOT isolate the electrical supply to the burner.

WARNING
After the burner has been switched off (either manually using the burner ON/STANDBY switch on the control panel,
automatically by the boiler temperature control, or the heating system controls) the burner needs to burn-down the
remaining pellets in the brazier.

Do not open the front combustion chamber access door until “WAIT BOILER THERMOSTAT” is showing on the burner
control panel display.

• OVERHEAT thermostat:

This is a built-in safety device to automatically shut down the boiler if it overheats. If this device should operate, it can be manually reset
once the boiler has cooled down.

Switch the burner ON/STANDBY switch to ‘STANDBY’ and allow the boiler to cool down.

Then unscrew the plastic cap and press the reset button. If this overheat thermostat continually trips there may be a fault and you
should contact your Installer.

• CLEANING AUTO/TEST switch:

When pressed and held in the TEST position, it allows the installer or Grant service engineer to manually operate and test the automatic
cleaning systems in both heat exchangers. When released, it will automatically return to the default AUTO position to allow the boiler
cleaning system to perform automatically.

Only operate the cleaning switch when the boiler is not operating and ‘WAIT BOILER THERMOSTAT’ is showing on the burner control
panel display.

NOTE
The Cleaning Auto/Test switch does NOT operate the brazier cleaning system.

WARNING
After the burner has been switched off (either manually using the burner ON/STANDBY switch on the control panel,
automatically by the boiler temperature control, or the heating system controls) the burner needs to burn-down the
remaining pellets in the brazier.

Do not open the front combustion chamber access door until ‘WAIT BOILER THERMOSTAT’ is showing on the burner
control panel display.

If the burner door is opened during the operation of the burner there can be a large uncontrollable flame from the brazier.

NOTE
Avoid repeated opening and closing of the boiler door as this will cause the automatic cleaning of the boiler and burner
to be delayed. This can cause excessive ash build-up within the boiler and burner that may result in nuisance faults
occurring.

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5 Burner Control Panel

5.1 Burner Control Panel

The burner control panel is located on the upper front part of the red burner cover.

This control panel is used by the Installer or Grant Service Engineer to check and set the burner and boiler settings during commis­sioning or servicing.

The burner control panel display shows the following information:

Temperature Set Point

The set point is set by the Installer, during commissioning, using either button 1 or 2 (as shown below) within the range 55°C to 75°C.

Refer to Figure 5-1.

Typically it will be set to 70-75°C. This is the ‘target’ temperature setting about which the modulation of the boiler output will operate.

• 5°C below the set point, the boiler is in 100% power mode.

• 5°C above the set point, the boiler has reached minimum output.

The set point is NOT the temperature at which the burner stops. The maximum boiler temperature at which the burner will cut out is
factory set in the burner control settings. This can, if required, be adjusted by the installer or Grant service engineer.

Figure 5-1: Burner control panel display - temperature set point

Boiler System Water Temperature

This is the temperature of the water in the boiler. Refer to Figure 5-2.

Figure 5-2: Burner control panel display - boiler system water temperature

NOTE
When the burner cuts out, the temperature will continue to rise as the heat from the flame is transferred to the system
water in the boiler.

Burner Operating Modes

Figure 5-3: Burner control panel display - burner operating mode indication

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At any point during the start-up, running and shutting down of the burner, the burner operational mode is shown scrolling across the
bottom of the display screen. This can be one of several modes, depending on the operation of the boiler at the time it is viewed, as
follows:

• WAIT BOILER THERMOSTAT: boiler is in standby mode awaiting either a signal from the heating system controls and/or for the

burner ON/STANDBY switch to be set to ON to start the boiler, OR the temperature to fall to the Restart Temperature (5°C below
the set temperature)

• WAIT PRELOAD BRAZIER: initial loading of pellets into the burner brazier to enable the burner to be lit.

• WAIT LIGHTING: period of time taken for the pellets to light, for the flame to stabilise and then for small amounts of pellets to be

added to build up the flame in the brazier.

• PELLET BURNER FIRING – Power 100%: flame is fully developed and boiler is operating on full power.

• PELLET BURNER FIRING – Power 99% - 25%: boiler output is being modulated down.

• PELLET BURNER FIRING – Power 25%: boiler is operating at minimum output.

• TURNING OFF BRAZIER: burn-down period to remove any pellets remaining in the brazier.

• WAIT POST PURGE: period of time after burn-down is complete to ensure no unburnt pellets ignite.

5.2 Error Messages

The burner control panel display can also indicate that a fault has occurred with the boiler. In the event of a fault, one of the following
error (fault) messages may be seen scrolling across the bottom of the display screen:

• FAILED PELLET LIGHTING

• SERVO MOTOR BLOCKED

• PROBE FAULT

• AIR PRESSURE ERROR

5.3 Service Indicator

The burner will indicate when a service is required by showing the word ‘SERVICE’ on the control panel display. This will occur after a
preset period (400 hours of pellet auger running time) has elapsed. This equates to the consumption of 4.8 tonnes of pellets.

The boiler must be serviced either annually, or when you see the ‘SERVICE’ message on the burner control panel display, whichever
comes first. Contact you Grant Approved Installer and arrange for your boiler to be serviced.

5.4 Active Symbols

There are eight symbols on the left hand side of the burner control panel display.

These are the ‘active symbols’ that, when they have a cursor displayed next to them in the screen area, indicate what functions the
burner is operating at any point when the boiler is running.

Figure 5-4: Burner control panel display – active symbols

The function indicated by each of these ‘Active Symbols’ is as follows:

Symbol Function

Heating demand (from heating system controls)

Burner fan operational

Air pressure switch closed

Ignition element operational

Pellet feed auger operational

Flame on

Not applicable

Fault

Table 5-5: Active symbols

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6 Pellet Feed Tube Thermostat

This is a built-in safety device, mounted on the pellet feed tube (on the top of the
burner) to automatically shut down the burner if the temperature on the pellet feed tube
(between the pellet auger and the burner) exceeds a safe level.

If this device should operate, it can be manually reset once the boiler and pellet feed
tube has cooled down.

To reset:

• Isolate the electrical supply to the boiler (set the switch on the fused spur to off).

• Remove the red burner cover by loosening the four M5 screws (two on each side

of the cover) and lifting it off the burner. The thermostat is located on the pellet
feed tube. Refer to Figure 6-1.

• Disconnect the lead from the thermostat terminals. Refer to Figure 6-2.

• Press the reset button located between the two terminals.

• Reconnect the lead. Ensure it is fully pushed on to thermostat terminals.

• Finally, refit the burner cover and tighten the four screws.

• Reconnect the electrical supply to the boiler and check operation.

NOTE
There is no power present on the two thermostat terminals when the lead has
been disconnected, so there is no risk of electrocution when resetting the
thermostat.

Figure 6-1: Location of pellet feed tube
thermostat

7 Priming the Auger

The pellet feed auger on the pellet hopper MUST be fully primed BEFORE attempting
to start the boiler. The auger should be initially primed by the Installer as part of the
commissioning process.

If for any reason the auger needs to be re-primed, this is a simple process using the
following procedure:

Step 1

First set the burner ON/STANDBY switch to the STANDBY position.

Step 2

Disconnect the pellet feed auger 6-way plug (3) from the upper socket on the left side
of the burner. Refer to Figure 7-1.

Step 3

Disconnect the 7-way plug (1) from the socket on the left side of the burner. Refer to
Figure 7-2.

Step 4

Disconnect the pellet delivery hose from the pellet feed tube (on the burner) and place
the open end into a DRY container of at least 1 litre capacity. Refer to Figure 7-3.

Figure 6-2: Disconnect lead from pellet tube
thermostat

Figure 7-1: Remove plug 3 from burner

Figure 7-2: Remove plug 1 from burner

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Step 5

Insert the 6-way plug (3) into the 7-way plug (1). Refer to Figure 7-4. It is not possible
to connect these two plugs incorrectly as they will only fit together one way. When
these plugs are connected the pellet feed auger will run continuously.

Step 6

Leave the auger running until there is a continuous flow of pellets from the pellet
delivery hose. This may take 15 to 20 minutes. The pellet feed auger is now fully
primed.

Step 7

Disconnect the two plugs from each other and the auger will stop.

Refit the pellet delivery hose onto the pellet feed tube of the burner.

WARNING
Ensure that the pellet delivery hose forms an air tight seal each end and
that the hose is not damaged. Leakage of air could cause increased
temperature in the pellet delivery hose and result in the pellet feed tube
thermostat shutting down the burner.

Step 8

Re-fit both the 6-way and then 7-way plugs to their corresponding sockets on
the left side of the burner. Ensure that both plugs are fully pushed home until the
small catch on each plug clicks into place.

Step 9

Make sure that the boiler pellet hopper is correctly located against the side of the
boiler with the front edge aligned with the top front edge of the boiler. Refer to
Figure 7-5.

Step 10

Finally, set the burner ON/STANDBY switch to the ON position.

8 Lighting your Boiler

To start your boiler:

• First ensure that the electrical supply to the hopper and boiler is switched on.

• Check that the heating system controls are operating and are ‘calling’ for

heat. There should be a cursor next to the ‘Heating Demand’ symbol on the
burner display. Refer to Section 5.4 – Active Symbols.

• Set the burner ON/STANDBY switch to ON. The flue fan will start and pellets

will be delivered to the burner for it to start.

NOTE
If the burner ON/STANDBY switch is switched to STANDBY at this stage
the pellet feed will continue, and then the burner will go through the ‘WAIT
BOILER LIGHTING’ phase and light.

It will then immediately go to ‘TURNING OFF BRAZIER’ followed by ‘WAIT
POST PURGE’ and then stop.

This process will take several minutes to complete before the boiler can be
re-started.

• The flue fan will start and pellets will be delivered to the burner. The boiler will
now light automatically after a short ignition period.

• Set the heating (CH) and hot water (HW) functions on your programmer
to ‘Timed’. The boiler will now operate during the ‘on’ periods set on the
programmer.

CAUTION
Do not repeatedly switch the ON/STANDBY switch on and off the burner
at this stage, as a build-up of pellets in the brazier will occur resulting in
poor combustion during lighting.

Figure 7-3: Pellet tube ready for priming the
pellet auger

Figure 7-4: Connect plugs together

Figure 7-5: Correct alignment of hopper to
boiler.

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9 If your Boiler Fails to Light

If you experience a problem with your boiler, it may be due to something quite simple and by making a few checks you can quickly
rectify it for yourself. If your boiler fails to light, please follow the procedure given below, starting with STEP 1:

STEP 1

STEP 2

STEP 3

Is the burner control panel display blank?
NO - go to STEP 2

YES – Check the following:

• Is the electrical supply to boiler and heating system controls switched on at fused spur?

• Has the fuse in the fused spur blown?

• Are all the plugs at the rear of the hopper, the rear of the boiler and the side of the burner fitted

correctly?

• Is the combustion chamber door closed and the catch fully engaged?

• Has the boiler overheat thermostat tripped? Remove cap to check. If yes, press the reset button.

Refer to Section 4. If this does not rectify the problem, contact your Installer.

• Has the pellet feed tube thermostat tripped? Reset the thermostat. Refer to Section 6 – Pellet Feed

Tube Thermostat for details. If this does not rectify the problem, contact your Installer.

If, after checking the above, there is still a problem then contact your Installer for assistance.

Is one of the four ERROR MESSAGES scrolling across the bottom of the burner control panel display?
YES – go to STEP 4

NO – go to STEP 3

Is there a cursor next to the ‘Heating Demand’ symbol on the burner display?
YES – Check the temperatures on the burner display.

• Is the H2O value on the display higher than the set point temperature value plus 5°C. If so, there is

NO fault but the boiler is waiting for the system temperature to drop before firing again.

NO – Check the following:

• Is the burner STANDBY/ON switch set to the ON position? If not, then set it to ON.

• Is there a sufficient quantity of pellets in the pellet hopper? If not, top up the hopper with pellets.

• Are the heating system controls (programmer, room thermostat, etc.) ‘calling’ for heat? If not, set

controls to call for heat.

STEP 4

If, after checking the above, there is still a problem then contact your Installer for assistance.

Which one of the four ERROR MESSAGES is scrolling across the bottom of the burner control panel
display?

• FAILED PELLET LIGHTING – go to STEP 5

• SERVO MOTOR BLOCKED – go to STEP 6

• PROBE FAULT – go to STEP 7

• AIR PRESSURE ERROR – go to STEP 8

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STEP 5

STEP 6

FAILED PELLET LIGHTING is scrolling across the bottom of the burner control panel display.

Check the following:

• Is there a sufficient quantity of pellets in the pellet hopper? If not, top up the hopper.

• Is the pellet auger fully primed? If not, prime the auger. Refer to Section 7.

• If there is a bulk pellet store, Are there pellets in the bulk store? Refer to Section 2 – Bulk pellet stores.

• Is the bulk store auger (if fitted) fully primed? Refer to Section 2 – Bulk pellet stores.

• If a Grant SpiraVAC vacuum system is fitted, is it delivering pellets to the pellet hopper? Refer to

Instructions supplied with the SpiraVAC system.

• Are pellets being delivered to the burner by the pellet hopper auger? If not, check the following:

a) Is the auger rotating? If not, check if the auger power supply lead is correctly plugged in to the
burner.
If it is still not rotating then contact your Installer.
b) Is there a build-up of dust in the bottom of the hopper? If so, this dust MUST be removed from
the hopper
and auger, and the auger then must be re-primed. Refer to Section 7.

NOTE

Pellets that contain an excessive amount of dust will prevent the auger from pulling the pellets out of the
hopper. The hopper will need to be cleaned of any dust.

• With the burner STANDBY/ON switch set to the STANDBY position, remove the pellet feed tube from

the burner and open the combustion chamber door.

• Is the brazier blocked with ash/clinker? If yes, is the correct grade of pellets being used? If not, empty

the hopper and refill with correct grade of pellet.

If, after checking the above, there is still a problem then contact your Installer for assistance.

SERVO MOTOR BLOCKED is scrolling across the bottom of the burner control panel display.

Check the following:

• With the burner STANDBY/ON switch set to the STANDBY position, remove the pellet feed tube from

the burner and open the combustion chamber door.

• Is the brazier blocked with ash/clinker? If yes, remove the blockage and close the combustion

chamber door. Reset the STANDBY/ON switch to ON and wait for the cleaning process to be
completed.

If, after checking the above, there is still a problem then contact your Installer for assistance.

STEP 7

PROBE FAULT is scrolling across the bottom of the burner control panel display.

Check the following:

• Are the three plugs correctly fitted to the left side of the burner?

• Press the RESET button on burner control panel to clear error message.

If, after checking the above, there is still a problem then contact your Installer for assistance.

STEP 8

AIR PRESSURE ERROR is scrolling across the bottom of the burner control panel display.

Check the following:

• Press the RESET button on the burner control panel to clear error message.

If there is still a problem then contact your Installer for assistance.

WARNING

Do not under any circumstances enter a bulk pellet store or pellet hopper that has been in operation as there may be a build-up of
fumes within the enclosure if the boiler has malfunctioned.

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10 Emptying the Ash Pan

It is essential that the ash pan (located inside the boiler
combustion chamber) is periodically emptied.

This simple task must be carried out by the user at MONTHLY
intervals for the FIRST THREE MONTHS after the boiler is
installed.

After that the ash pan should be emptied regularly, on at least
a MONTHLY basis, or as indicated by the amount of ash found
during the first three months.

NOTE

The amount of ash produced varies between the different
pellet brands and this will affect the frequency of cleaning and
maintenance required.

To remove and empty the ash pan you will need the following
items (supplied with the boiler):

• The removable door handle – to open the combustion

chamber door. Refer to Figure 10-1.

• The ash pan carrying handles – to remove and carry the ash

pan when hot. Refer to Figure 10-2.

To remove and empty the ash, follow the procedure below:

Figure 10-1: Removable door handle

Figure 10-2: Carrying handles

Step 1

Set the burner STANDBY/ON switch to ‘STANDBY’.

Step 2

If the boiler is running at the time, wait for it to complete the burner
shut-down sequence, i.e. until the burner control panel display
screen reads ‘WAIT PELLET THERMOSTAT’.

WARNING
After the burner has been switched off (either manually
using the burner ON/STANDBY switch on the control panel,
automatically by the boiler temperature control, or the
heating system controls) the burner needs to burn-down the
remaining pellets in the brazier.

Do not AT ANY TIME open the front combustion chamber
access door until the burner display reads “WAIT BOILER
THERMOSTAT”

Step 3

Allow the burner to cool down, for a period of at least 30 minutes.

Step 4

Disconnect the pellet delivery hose from the pellet feed tube on
the burner. Refer to Figure 10-3.

Figure 10-3: Disconnect pellet hose from burner

14

Step 5

Fit the removable door handle into the slot in the door catch. Refer
to Figure 10-4.

Figure 10-4: Fitting the removable door handle

Step 6

Lift the handle to disengage the catch and fully open the
combustion chamber door. Refer to Figure 10-5.

Figure 10-5: Opening combustion chamber door

WARNING
The interlock on the combustion chamber door
automatically disconnects the power supply to the burner if
the door is opened.

IT DOES NOT IMMEDIATELY EXTINGUISH THE BURNER
FLAME.

If the burner door is opened during the operation of the
burner there can be a large uncontrollable flame from the
brazier.

Step 7

Hook one of the two carrying handles (supplied with the boiler)
under the front edge of the ash pan and carefully pull the ash pan
forward by about 300mm (12inches). Refer to Figure 10-6.

Step 8

Brush/scrape any ash resting on the burner into the ash pan
below.

Step 9

Using both of the carrying handles, one at the front and the other
at the back, carefully lift the ash pan out of the boiler. Refer to
Figure 10-7.

Figure 10-6: Removal of ash pan from boiler

Figure 10-7: Lifting ash pan using carrying handles

Figure 10-5: Opening combustion chamber door

Do NOT use the centre cross bar of the ash pan as a
carrying handle.

Step 10

Safely dispose of the ash.

WARNING
Extreme care is required when emptying the ash pan as
smouldering ash could be present and can cause serious
damage to persons or property.
Ensure the ash is disposed of in a safe manner.

Step 11

Remove any remaining ash that may be left in the base of the
boiler before putting the ash pan back into the combustion
chamber.

Step 12

Close the combustion chamber door and ensure that the door
catch is fully engaged.
Remove the door handle and keep in a safe place for future use,
along with the carrying handles.

Figure 10-6: Removal of ash pan from boiler

Figure 10-7: Lifting ash pan using carrying handles

15

11 Cleaning and Servicing your Boiler

The boiler MUST be serviced either ANNUALLY or when a service is indicated on the burner control panel display, whichever comes
FIRST. Refer to Section 5.

Servicing should only be carried out by a Grant trained installer or Grant service engineer, and details of each service should be
recorded in the Service Log in Section 17 of these User Instructions.

CAUTION
Failure to regularly service the boiler will invalidate the terms of the Grant product guarantee.

Failure to maintain a clean flue may result in the release of flue gases into the dwelling or damage from potential fire in the flue. It is
therefore essential that your flue is inspected annually and cleaned as necessary by either a Grant trained installer or a suitably qualified
chimney sweep.

12 Ventilation

As an ‘open flued’ appliance, your Grant Spira boiler draws the air it requires for combustion from the room in which it is located. In turn,
this air comes from outside via a permanently open air vent (or vents) correctly sized to meet the air requirements of your boiler.

WARNING
Any permanently open combustion air vents in the room containing the boiler MUST NOT be blocked off or obstructed in
any way. Do not attempt to ‘box in’ the boiler, or build a compartment around it, without contacting your installer first for
guidance.

Do NOT place any combustible material against, around or on the boiler or flue pipe.

Current Building Regulations require that a Carbon Monoxide alarm (conforming to BS EN 50291:2001) must be fitted in the room
where the boiler is located.

This should be positioned between 1 and 3metres horizontally from the boiler either:
a) On the ceiling, at least 300mm from any wall

or

b) On a wall as high up as possible (above any windows or doors) at least 150mm from the ceiling.

13 Electricity Supply

If the electricity supply fails, the boiler will cease to operate. It should automatically relight when the electrical supply is restored.
However, it may first burn off any smouldering pellets still present in the brazier before starting the lighting sequence again.

If a remote programmer is connected to your boiler, it may have a ‘battery back-up’ of some kind that will retain the on/off time settings
you previously entered. It may also resume operation with the correct time of day and thus require no re-setting of time and on/off
settings when the supply is restored. Refer to the instructions supplied with your programmer for further details. It is recommended that
you check that the on/off and time settings after a power failure has occurred.

WARNING
The electricity connections to the boiler must be earthed.

14 Sealed Heating System

If your boiler is operating on a sealed heating system, the installer will have adjusted the pressure in the system and should have told
you (or set it on the pressure gauge) the system pressure when cold. This is normally between 0.5 and 1.0 bar, which will increase
slightly when hot. If the pressure (when cold) is below the set pressure mentioned above, you can re-pressurize the system. If this is
frequently required, ask your Installer or service engineer to check the heating system for leaks and to check the expansion vessel air
charge.

The boiler or system will be fitted with an automatic air vent to remove any air from the system. Any trapped air in the radiators should
be removed by venting the radiators using the vent screw at the top of each radiator. Only vent a radiator if the top is cool and the
bottom is hot.

Excessive venting will reduce the system pressure, so only vent when necessary and check the system pressure as mentioned above.

Re-pressurise the system as necessary.

The sealed system is fitted with a safety valve to release excess pressure from the system. If water or steam is emitted from the end of
the safety valve discharge pipe, switch off the boiler and contact your Installer for assistance.

16

15 Frost Protection

Your installer may have fitted a frost thermostat. If not, and you are likely to be away for a short time, leave the boiler on with the room
thermostat set at a low setting. For longer periods, the boiler should be turned off and the system drained down. Contact your Installer
for draining and re-filling the system. Alternatively, a suitable anti-freeze may have been added to the heating system water. Check with
your installer.

16 Corrosion Protection

In order to prevent corrosion within your heating system and boiler, your installer should have flushed the system and added a suitable
corrosion inhibitor.

NOTE

The Grant Guarantee on the boiler shell (heat exchanger) requires that the heating system is flushed or chemically
cleaned, following installation, and the required quantity of corrosion inhibitor is added to the heating system water.

Grant strongly recommends that an in-line magnetic filter (either a Grant Mag-One or equivalent*) is fitted in the heating
system pipework.

This should be installed and regularly serviced in accordance with the filter manufacturer’s instructions.

*The Grant Mag-One magnetic filter has a Gauss measurement of 12000.

17

17 Service Log

Heating System

System pressure – check/top up

Pressure relief valve operation - check

Expansion vessel charge pressure – check

Magnetic filter – inspect/clean

Corrosion inhibitor in system – check

Flue System

Flue terminal – check condition

Flue system – check clean

Draught stabilizer – check operation

Smoke test (Smoke test II Part J. Section E15)

Combustion ventilation – check

Boiler

Temperature probe – check

Overheat thermostat – check

Primary heat exchanger – inspect/clean

Secondary heat exchanger – inspect/clean

Wash system – inspect/clean

Combustion chamber – inspect/clean

Fan – inspect/clean

Shaker mechanism - grease

Shaker system – check operation

Condensate trap – inspect/clean

Condensate discharge pipe – inspect/clean

Burner

Brazier – dismantle/clean

Photocell – inspect/clean

Ignition element – inspect/clean

Boiler settings – check

Safety devices

Hopper lid switch – check operation

Combustion door switch – check operation

Pellet Hopper

Check for dust build-up

Auger – check for blockages

Combustion

Combustion chamber draught – check/adjust

Flue gas analysis – check/adjust

Customer handover

Service Date

Service Company

Service 1 Service 2 Service 3 Service 4 Service 5

18

Signature

This page is intentionally left blank

19

Installation and Servicing
Instructions - contents

1 Introduction 21

1.1 How the Condensing 22
Wood Pellet Boiler Operates

1.2 Boiler Description 22

1.3 Boiler Models 22

1.4 Boiler Components 23

1.5 Boiler Cleaning and 24
Servicing

1.6 Removable Door Catch 24
Handle

2 Technical data 25

2.1 Boiler and Hopper 25
Technical Data

2.2 Boiler Input and 26
Output Data

2.3 Flue Gas Analysis 26

2.4 Boiler and Hopper 27
Dimensions and Clearances

3 Pellet Specification, 30
Storage and Delivery

3.1 Pellet Specification 30

3.3 Biomass Suppliers List 30

3.2 Pellet Storage 31

4 Installation information 33

4.1 Introduction 33

4.2 Boiler Location 33

4.3 Preparation for Installation 33

4.4 Installing the Boiler 33

4.5 Regulations 33

4.6 Heating System Design 33
Considerations

4.7 Pipework Materials 33

4.8 Pipe Connections 34

4.9 Wash System 34

4.10 Fan Box and Flue Starter 34

4.11 Pellet Feed Tube 35

4.12 Pellet Hoppers 36

4.13 Pellet Feed Auger 36

4.14 Before you Commission 36

4.15 Completion 36

6 Sealed Systems 39

6.1 Sealed System 39
Requirements

6.2 Filling the Sealed System 40

6.3 Venting the Pump 40

6.4 Pressure Relief (Safety) 40
Valve Operation

7 Flue System and 41
Air Supply

7.1 Air Supply 41

7.2 Flue Terminal Position and 41
Clearances

7.3 Flue System Specification 43

7.4 Flue System Assembly 43

7.5 Flue Testing 46

7.6 Flue Notice Plate 46

7.7 Carbon Monoxide Alarm 46

7.8 Typical Flue Systems 47

7.9 Flue Component Dimensions 48

7.10 Flue System Components 49

7.11 Flexible Flue Liner 51

8 Electrical 52

8.1 General Requirements 52

8.2 Hopper Electrical 52
Connections

8.3 Boiler/Hopper Plug 53
Connections

8.4 Heating System Controls 54

8.5 Connecting the Power 54
Supply

8.6 Wiring Diagrams 55

9 Burner 61

9.1 Burner Operation 61

9.2 Burner Operating Modes 61

9.3 Burner Operating Sequence 62

9.4 Burner Display Screen 63

9.5 Burner Control Buttons 63

9.6 Burner Menu Navigation 64
Chart and Factory Default
Settings

9.7 Burner Menu 65

10.10 Flue Gas Analysis 72

10.11 Customer Handover 73

10.12 Commissioning Report Form 73

10.13 Commissioning Check List 73

11 Servicing 74

11.1 General 74

11.2 Checks Before Servicing 74

11.3 Heating System 74

11.4 Flue System 75

11.5 Combustion Ventilation 75

11.6 Boiler 75

11.7 Burner Brazier 77

11.8 Burner Components 78

11.9 Refitting the Burner 79

11.10 Condensate Disposal 79
System

11.11 Cleaning Function Test 79

11.12 Burner Settings 80

11.13 Safety Device Checks 80

11.14 Combustion Checks 80

12 Fault Finding 81

12.1 General 81

12.2 Normal Screen Display 82

12.3 No Screen Display 83

12.4 Boiler Overheat Thermostat 85

12.5 Pellet Feed Tube Thermostat 87

12.6 Failed Pellet Lighting 89

12.7 Servo Motor Blocked 91

12.8 Probe Fault 92

12.9 Air Pressure Error 93

13 Spare Parts 95

13.1 Boiler 95

13.2 Boiler Parts List 96

13.3 Burner 98

13.4 Burner Parts List 99

13.5 110kg Pellet Hopper 100

13.6 200kg Pellet Hopper 100

13.7 140kg Pellet Hopper 101

13.8 Pellet Hopper Parts List 101

20

5 Condensate disposal 37

5.1 General Requirements 37

5.2 Connections 37

5.3 Pipework 37

5.4 External Pipework 37

5.5 Condensate Trap 38

5.6 Inspection and Cleaning 38
of Trap

10 Commissioning 68

10.1 Equipment Required 68

10.2 Preliminary Inspection 68

10.3 Boiler 68

10.4 Pellet Hopper 69

10.5 Safety Device Checks 69

10.6 Burner Settings 70

10.7 Priming the Pellet Feed 70
Auger

10.8 Lighting the Boiler 71

10.9 Combustion Chamber 71
Draught

14 Clean Air Act and 102
Declaration of

Conformity

14.1 Clean Air Act 102

14.2 Declaration of Conformity 102

15 Health and Safety 103
Information

15.1 Insulation Materials 103

15.2 Sealant and Adhesive 103

16 Guarantee 104

1 Introduction

Figure 1-1: Grant Spira Condensing Wood Pellet Boiler and Intermediate Hopper

This manual is intended to guide
Installers who have completed the
Grant Wood Pellet Boiler Installer
training course on the installation,
commissioning and servicing of the
Grant Spira Condensing Wood Pellet
Boiler.

A separate manual is available to guide
users in the operation of the boiler.

The following special text formats are
used in this manual for the purposes
listed:

!

WARNING

Warning of possible human injury
as a consequence of not following
the instructions in the “warning”.

!

CAUTION

Caution concerning likely
damage to equipment or tools as
a consequence of not following
the instructions in the “Caution”.

!

NOTE

Used for emphasis or information
not directly concerned with the
surrounding text but of importance
to the reader.

21

22

1.1 How the Condensing Wood Pellet Boiler Operates

On start up, the auger feeds the wood
pellets from the hopper into the burner
where they are lit by an ignition element.
The burner output is modulated
to achieve the set temperature by
controlling the feed rate of pellets.
The fan in the burner propels hot
gases generated from the fuel into
the Spira’s primary heat exchanger.
The heat energy is then transferred to
water from the central heating system,
before being circulated around the
property to radiators/underfloor heating.
It is important to note that in non­condensing biomass boilers, up to 20%
of the energy that is produced is lost to
the atmosphere through waste gases
exhausted by the flue system.

The Spira contains a unique extra
(secondary) condensing heat
exchanger which has been designed to
capture some of this lost heat energy
that would otherwise be lost, so it
maintains extremely high efficiencies.

It does this by cooling the flue gases
to their dew point (below 55°C) thus
extracting more sensible heat.

The boiler has been independently
tested to BS EN303-5 and will achieve
the following full load (nett) efficiencies
when both the boiler and system are
correctly set:

Model Nominal Reduced
output output

Spira 5-18 95.5% 90.2%

Spira 6-26 97.4% 96.4%

Spira 9-36 93.1% 98.1%

To ensure maximum efficiency from
the Grant Spira boiler, the boiler
return temperature should be 55°C
or less (but NOT less than 40°C) at
maximum operating temperature.
This will enable the latent heat to be
condensed out of the flue gases.

The boiler is capable of a maximum
flow temperature with a maximum set
point of 75°C.

To achieve the required return
temperature (55°C or less), it is
recommended that the heating system
is designed and balanced to operate
with a temperature differential of 20°C
between flow and return. The use of
modulating circulating pumps and
effective control systems should be
considered.

Grant Spira condensing wood pellet
boilers will still operate at extremely

high efficiencies even when not in
condensing mode and are therefore
suitable for fitting to an existing heating
system without alteration to the radiator
sizes.

1.2 Boiler Description

The Grant Spira boiler uses a drop feed
type burner with modulated heat output.
The burner output is determined by
varying the feed and pause times of the
pellet feed auger supplying pellets to
the burner. See Section 9 for details of
burner operation.

The boiler is suitable for use on a
sealed or open vented central heating
system. When commissioned and set
correctly, Grant Spira condensing wood
pellet boilers will operate automatically,
using a typical heating control system.

All models are supplied with the control
panel and burner factory fitted. The
fan box, pellet feed auger and hopper
are supplied separately and are fitted
by the installer. See Section 4 for
boiler installation. The boiler needs
to be connected to a conventional
flue system. There is no provision for
connection to a balanced flue system

Product code Model Description

WPS518 RH110 5-18 1 x 5-18kW boiler + 110kg right hand hopper

WPS518 LH110 5-18 1 x 5-18kW boiler + 110kg lef t hand hopper

WPS518 RH200 5-18 1 x 5-18kW boiler + 200kg right hand hopper

WPS518 LH200 5-18 1 x 5-18kW boiler + 200kg lef t hand hopper

WPS626 RH110 6-26 1 x 6-26 boiler + 110kg right hand hopper

WPS626 LH110 6-26 1 x 6-26 boiler + 110kg lef t hand hopper

WPS626 RH200 6-26 1 x 6-26 boiler + 200kg right hand hopper

WPS626 LH200 6-26 1 x 6-26 boiler + 200kg lef t hand hopper

WPS936 RH110 9-36 1 x 9-36 boiler + 110kg right hand hopper

WPS936 LH110 9-36 1 x 9-36 boiler + 110kg lef t hand hopper

WPS936 RH200 9-36 1 x 9-36 boiler + 200kg right hand hopper

WPS936 LH200 9-36 1 x 9-36 boiler + 200kg lef t hand hopper

WPS1144 11-44 1 x 5-18kW and 1 x 6-26kW boilers + 140kg double boiler

WPS1252 12-52 2 x 6-26kW boilers + 140kg double boiler hopper

WPS1562 15-62 1 x 6-26kW and 1 x 9-36kW boilers + 140kg double boiler

WPS1872 18-72 2 x 9-36kW boilers + 140kg double boiler hopper

as there is draught stabiliser fitted to the
appliance.

The boiler is not designed specifically
for operation on a system with a buffer
tank/ thermal store, however when used
on such a system there is no effect on
the boiler performance.

!

NOTE

The only flue suitable for use with
the Grant Spira condensing wood
pellet boiler is the Grant Biomass
twin-wall insulated conventional flue
system.

This 125mm (5”) diameter flue
system is suitable for the 5-18kW,
6-26kW and 9-36kW Spira models.

For the 44kW, 52kW, 62kW and
72kW double boiler installations
each boiler must have a separate

flue system. Refer to Section 7.

1.3 Boiler Models

The Grant Spira condensing wood
pellet boiler is available in sixteen
different models:

hopper

hopper

1.4 Boiler Components

1.4.1 Burner. The burner is supplied

factory-fitted to the boiler. All burners are
supplied with factory default settings.
During commissioning each burner
parameter will need to be checked (see
Section 9), and adjusted if necessary
as the flue length can have a significant
effect on the boiler performance. Refer
to commissioning in Section 10.

The burner is equipped with a self
cleaning device to prevent a build up of
ash and clinker in the burner brazier.

All Spira boilers are fitted with a flame
viewing window, located on the right
hand side of the front combustion
chamber door, just above the burner.

The burner output is determined by the
feed / pause times of the pellet feed
auger supplying the burner. See Section
9 for full burner operation details.

1.4.2 Boiler. The Spira condensing
boiler is supplied with a combined
primary and secondary heat-exchanger.
Both heat exchangers are equipped
with a self cleaning system.

1.4.3 Boiler controls. The set-point
temperature of the boiler is user
adjustable via two push buttons on the
burner control panel - see Section 9.4
for details.

The boiler control panel (see Figure 1-2)
is located at the top of the boiler and is
fitted with three controls, as follows:

ON/STAND-BY switch – to switch
off the burner when required, by
interrupting the switched live supply to
the burner. This switch does not isolate
the electrical supply to the burner.

OVERHEAT thermostat - this allows
the boiler to be used on a sealed central
heating system and will automatically
switch off the boiler if the pre-set
temperature of 100°C is exceeded.

CLEANING switch - when pressed
and held in the TEST position, it
allows the cleaning system to be
manually operated and tested. When
released it will automatically return
to the default AUTO position to allow
the boiler cleaning system to perform
automatically. Only operate the cleaning
switch when the boiler is not operating

- when ‘WAIT BOILER THERMOSTAT’ is
showing on the burner display screen.

!

NOTE

‘TEST’ does NOT operate the burner
cleaning function, but only that of
the two heat exchangers.

Figure 1-2: Boiler control panel

!

WARNING

After the burner has been switched
off (either manually by the switch on
the control panel, or automatically
by the boiler control stat, or the
heating system controls) the
burner needs to burn-down the
remaining pellets in the brazier.
Do not open the front combustion
chamber access door until the
burner display reads “WAIT BOILER
THERMOSTAT”.

1.4.4 Boiler Pellet Hoppers. All single

boilers (Spira 5-18, 6-26 and 9-36
models) come with a pellet hopper. Two
sizes of hopper are available for use
with single boilers, as follows:

• 110 kg hopper – for storing a
maximum of 110kg
(≈170 litres) of wood pellets

• 200kg hopper – for storing a
maximum of 200kg
(≈308 litres) of wood pellets.

There are two versions of both the
110kg and 200kg pellet hopper
available for use with a single boiler:

Left hand hopper – to be positioned
on the left hand side of the boiler.

Right hand hopper – to be positioned
on the right hand side of the boiler.

!

NOTE

The hopper type must be specified
when ordering.

Both hoppers are supplied with a single

1.2m pellet feed auger, to be fitted to
the hopper on site by the installer.

All ‘double boiler’ installations (Spira
11-44, 12-52, 15-62 and 18-72 models)
come with one ‘double’ hopper to feed
both boilers with two 1.2m pellet feed
augers.

This hopper is positioned between the
two boilers and stores a maximum of
140 kg (≈215 litres).

All the Grant pellet hoppers are for
indoor use only and must be positioned
in a dry environment.

Hopper contents switch

All hoppers are fitted with a contents
switch. This detects when the level of
pellets in the hopper falls to a pre-set
minimum value. If a bulk store is used,
this triggers the operation of either a
bulk store auger, or vacuum system,
to delivery pellets from the bulk pellet
store.

If no bulk store is used, the contents
switch will stop the burner operating
when the minimum pellet level is
reached or low level warning light.

Topping up the hopper with more
pellets will automatically operate the
contents switch and the burner will
restart (if there is a demand for the
boiler to run).

The minimum quantity of pellets
required to restart the boiler is 20kg for
the single boiler hoppers and 30kg for
the double boiler hoppers.

All boiler pellet hoppers are for
indoor use only and MUST be
positioned in a dry environment free
from dampness. They must be located

on the same floor level as the boiler or
boilers, they are supplying.

All hoppers are mounted on castors
(with the two front castors lockable)
to allow it to be easily moved when
required. Allow sufficient area in front of
the hopper for it to be moved out and
away from the boiler(s) during servicing.

The electrical connections to the
boiler(s) are all made to the 4-way
electrical plug on one of the three
factory-fitted ‘flying leads’ at the rear
of the hopper. Refer to Section 8 for
details.

23

All hoppers are supplied with a
rectangular blanking plate fitted on the
top rear panel. This can be removed, as
required, to allow the fitting of the Grant
SpiraVac pellet feed system. Refer to
installation instructions supplied with
the Grant SpiraVac system for further
details.

This blanking plate has a single round
‘knock-out’ to provide an entry into
the hopper from an auger supplying
pellets from a bulk hopper system.
This knockout is positioned to ensure
the pellets drop into the hopper and
operate the hopper contents switch.
Only this opening MUST be used
as making another opening in the
intermediate hopper could affect the
operation of the contents switch.

Electrical connection for either a bulk
auger or Grant SpiraVac system, if
required, is made using the 6-way
electrical plug and flying lead supplied
factory-fitted at the rear of the hopper.
Refer to Section 8 for connection
details.

Always ensure that the door and top
panel of the boiler hopper are fitted
to ensure no foreign debris enters the
hopper. If a bulk system with an auger
is fitted, ensure that the bulk auger
does not impede the opening of the
hopper door.

1.4.5 Pellet Feed Auger. All Grant
hoppers are supplied with either one
or, on double boiler hoppers, two

1.2m pellet feed augers. These are set
at a fixed angle of 45° to maintain a
consistent feed. If the pellet feed auger
angle is altered the input to the boiler
will also be altered.

The pellet feed auger is a hollow spiral
type. Its function is to deliver the pellets
from the hopper to the burner. The
output of the boiler is determined by
varying the on/off periods of the pellet
feed auger motor. Refer to Section 3.2
for pellet feed data.

1.5 Boiler Cleaning and Servicing

Grant Spira condensing wood pellet
boilers are equipped with an automatic
cleaning system for each of the two
heat exchangers and also for the burner
brazier.

!

CAUTION

The ash pan (located inside the
combustion chamber) will need to
be periodically emptied. This simple
task must be carried out by the
user at MONTHLY intervals for the
FIRST THREE MONTHS. Thereafter,
the ash pan should be emptied
regularly, on at least a monthly
basis, or as indicated by the amount
of ash found during the first three
months. Two carrying handles are
supplied with the boiler to allow
removal of the ash pan when hot.
Refer to Figure 1-3

Figure 1-3: Removable carry handles

!

WARNING

Care must be taken to avoid contact
with hot surfaces.

Always wait for the boiler to
cool down before opening the
combustion chamber door and
removing the ash pan.

The boiler MUST be serviced either
ANNUALLY or when a service is
indicated on the burner control
panel display, whichever comes
first. Servicing should only be
carried out by a Grant UK trained
Installer and details of each
service should be recorded in the
Service Log in the back of the user
instructions.

!

NOTE

The amount of ash produced varies
between the different pellet brands
and this will affect the frequency of
cleaning and maintenance required.

1.6 Removable Door Catch Handle

All Grant Spira boilers are supplied with
a removable handle for the combustion
chamber door catch. This must be
removed when the door is shut. Refer to
Figure 1-4.

To open the combustion chamber
door:

• Fit the removable door handle into
the slot in the door catch.

• Lift handle to disengage the catch
and open the door.

When closing the combustion
chamber door:

• Fully engage the door catch to
remake the door cut-out switch.

• Remove the handle and keep in a
safe place for future use.

Figure 1-4: Removable door catch
handle

24

2 Technical Data

2.1 Boiler and Hopper Technical Data

Units 5-18 6-26 9-36

Maximum heat output kW

Btu/h

Flow connection - 1” BSP (female) 1” BSP (female) 1¼” BSP (female)

Return connection - 1” BSP (female) 1” BSP (female) 1¼” BSP (female)

Water content litres 51.5 51.5 60

Minimum flow rate litres/hour 756 1 080 1 512

Water resistance ΔT = 10°C mbar 50

Water resistance ΔT = 20°C mbar 40

Mains water (cleaning system) bar 1 bar operating pressure

Minimum dynamic pressure bar 0.8

Maximum mains inlet water pressure kPa 800 (8 bar)

Minimum mains inlet water pressure kPa 100 (1 bar)

Condensate connection - 1¼” BSP (female)

Conventional flue - 125mm (5”) system

Combustion chamber draught requirement mbar 0.10 to 0.15 (running)

Maximum static head m 25

Minimum circulating head m 1

Boiler temperature set point range °C 55° to 75°C

Boiler temperature cut out point °C 65° to 80°C

Minimum return temperature °C 40°C

Water system overheat cut-out temperature °C 100°C

Burn-back overheat thermostat cut-out °C 90°C

Electrical supply - 230V~50Hz single phase

Max. operating pressure - sealed system / open system bar 2.0 bar

Max. operating pressure - pressure relief valve bar 2.5 bar

Maximum auger length (bulk hopper) metres 6.0

Maximum auger speed (bulk hopper) rpm 30

Minimum flue length metres 1.6

Maximum flue length metres 12.0

Heating element rating Watts 450

Intermediate auger motor power Watts 55

Intermediate auger motor starting current Amps 0.64

Intermediate auger motor running current Amps 0.64

Intermediate auger speed rpm 8.1

Flue fan motor power Watts 32

Flue fan motor starting current Amps 0.27

Flue fan motor running current Amps 0.13

Cleaning solenoid power Watts 10

Cleaning solenoid current Amps 0.087

Burner fan motor power Watts 56

Total burner start current Amps 2.5

Total burner run current Amps 0.60

18

61 400

26

88 700

36

122 800

25

2.2 Boiler Input and Output Data

The settings in the table below are
based on the boiler using the Grant
fixed angle pellet feed auger at 45° with
an auger motor fixed speed of 8.1 rpm.

Only EN Plus Grade A1 (BS EN ISO
17225-2) pellets MUST be used with the
Grant Spira boilers. These pellets must
be bark and sand free AND approved
by Grant BEFORE being used in the
Spira boilers. Failure to use approved
pellets will invalidate the product
guarantee.

2.2.1 Burner settings

All burner settings must be checked as
part of commissioning and servicing.
Refer to Section 9.6 for full details of
the burner settings and how to access,
check and, where necessary, how to
adjust them.

Model

5-18 45° 0025

6-26 45° 0025

9-36 45° 0065

Notes
*Heat input is based on a calorific value of 4.81 kWh/kg.
Heat input and output data given above is approximate only.
All burner settings must be checked as part of commissioning and servicing. Refer to Section 9.6 for full details of the burner settings
and how to access, check and, where necessary, how to adjust them.

Pellet

feed
auger
angle

Burner setting Heat

TIME

LOAD

MAX

(2.5 sec)

(2.5 sec)

(6.5 sec)

TIME

PAUSEkW(Btu/h)kW(Btu/h)

0048

(4.8 sec)

0025

(2.5 sec)

0025

(2.5 sec)36(122 832)

Boiler and Hopper Weights

Units 5-18 6-26 9-36

Weight boiler - less burner and fan box (empty) kg 201 201 231

Weight burner kg 25.5 25.5 25.5

Weight fan box kg 5 5 5

Total weight of boiler (empty) kg 232 232 262

Total weight of boiler (full) kg 283 283 322

Weight 110kg pellet hopper (empty) - incl. auger kg 41 41 41

Weight 110kg pellet hopper (full) - incl. auger kg 151 151 151

Weight 200kg pellet hopper (empty) - incl. auger kg 77 77 77

Weight 200kg pellet hopper (full) - incl. auger kg 277 277 277

Weight of auger kg 8 8 8

Weight 140kg double boiler hopper (empty) - incl.
2 augers

Weight 140kg double boiler hopper (full) - incl. 2
augers

MAX flame MIN flame

Draught CO

(in.wg)

(0.04-0.06)

(0.04-0.06)

(0.04-0.06)

output

17.8

(60 769)

26.3

(89 735)

Heat

input

18.6

(63 500)

27.1

(92 500)

38.7

(132 000)

Full
eff.

95.5 3.87 0.1-0.15

97.4 5.70 0.1-0.15

93.1 7.78 0.1-0.15

Input

kg/

%

hr*

mbar

kg 42 42 42

kg 182 182 182

Burner

2

setting

% TIME

PAUSE

MIN

10-12 0220

10-12 0140

10-12 0250

(22.0 sec)

(14.0 sec)

(25 sec)9(30 700)

(19 050)

(22 100)

Heat

output

kW

(Btu/h)

5.6

6.5

26

2.3 Flue Gas Analysis

As part of both the commissioning and
servicing procedures, the CO
of the flue gases must be checked. To
enable this to be done, the boiler is
supplied with a combustion test point
in the top rear cleaning door. Refer to
Figure 10-16.

To gain access to this test point, first
remove the top casing panel from the
boiler. The test point should be at the
back left corner of the rear cleaning
door. If it is located at the front right
corner of the cleaning door, then
remove the door and refit it with the test
point in the correct position.

content

2

!

NOTE

Use only a calibrated flue gas
analyser with a ‘Wood Pellet’ fuel
setting. Setting the fuel to anything
other than wood pellets will give an
incorrect reading.

!

CAUTION

To ensure correct combustion, the
burner settings given in the table
below must NOT be changed unless
instructed to do so by Grant UK.

!

CAUTION

Do not sample the flue gases
through either the draught stabiliser,
or from within the flue, as they will
have been diluted with air entering
through the draught stabiliser.

Only use the combustion test point
in the top rear access door to check
the CO

See Figure 10-16.

content of the flue gases.

2

2.4 Boiler and Hopper Dimensions and Clearances

2.4.1 Single Boiler with Left Hand Hopper

C

Front view

Air vent

511

Wash
system

255

1613

1417

1296

Side View

C

H

A

B

150

280

E

237

771

719

102

177

280

Flow
connection

Return
connection

Condensate
drain

Rear view

Hopper
wiring
centre

D

F

150

Plan view

134

G

225

150

Figure 2-1: Boiler and hopper dimensions and clearances – single boiler with left hand hopper

Spira wood pellet
boiler model

5-18 110kg left hand hopper 1056 518 513 177 96 661 1160 1120

5-18 200kg left hand hopper 1256 618 713 125 44 713 1160 1120

6-26 110kg left hand hopper 1056 518 513 177 96 661 1160 1120

6-26 200kg left hand hopper 1256 618 713 125 44 713 1160 1120

9-36 110kg left hand hopper 1056 518 513 277 196 661 1260 1220

9-36 200kg left hand hopper 1256 618 713 225 144 713 1260 1220

A B C D* E* F G* H

Dimensions

* If the measurement from the flue centre line to the rear wall is increased (shown as 134 in the plan view), then the dimensions D, E and G will have to be
increased by the same increment. All units in millimetres.

27

2.4.2 Single Boiler with Right Hand Hopper

D

E

F

511

255

1613

1417

H

1293

150

Side view

280

Plan view

A

B

C

150

Hopper
wiring
centre

Rear view

Front view

Flow
connection

Return
connection

458

Drain
cock

361

277

Air vent

Wash
system

719

400

134

G

771 237

225

Figure 2-2: Boiler and hopper dimensions and clearances – single boiler with right hand hopper

Spira wood pellet
boiler model

5-18 110kg right hand hopper 1056 518 513 177 96 661 1160 1120

5-18 200kg right hand hopper 1256 618 713 125 44 713 1160 1120

6-26 110kg right hand hopper 1056 518 513 177 96 661 1160 1120

6-26 200kg right hand hopper 1256 618 713 125 44 713 1160 1120

9-36 110kg right hand hopper 1056 518 513 277 196 661 1260 1220

9-36 200kg right hand hopper 1256 618 713 225 144 713 1260 1220

A B C D E F G H

Dimensions

28

* If the measurement from the flue centre line to the rear wall is increased (shown as 134 in the plan view), then the dimensions D, E and G will have to be
increased by the same increment. All units in millimetres.

2.4.3 Double Boiler with Central Hopper

1232

697

Front view

Air vent

237

771

719

Flow
connection

Return
connection

Condensate
drain

Drain
cock

Wash
system

Hopper
wiring
centre

Flow
connection

102 1231

177 1232

280 1232

H

280

EF

D

A

B

C

B

2801232

Return
connection

Drain
cock

150400

Air vent

Rear
view

Wash
system

772 237

134

1565

1417

1296

Plan view

Side view

Figure 2-3: Boiler and hopper dimensions and clearances – double boiler with central hopper

Spira wood pellet
boiler model

11-44 (5-18 and 6-26) with double hopper 1792 616 697 224 141 616 1160 1120

12-52 (2 x 6-26) with double hopper 1792 616 697 224 141 616 1160 1120

15-62 (6-26 and 9-36) with double hopper 1792 616 697 324 241 616 1260 1220

18-72 (2 x 9-36) with double hopper 1792 616 697 324 241 616 1260 1220

* If the measurement from the flue centre line to the rear wall is increased (shown as 134 in the plan view), then the dimensions D, E and G will have to be
increased by the same increment. All units in millimetres.

A B C D* E* F G* H

Dimensions

G

213

29

3 Pellet Specification, Storage and Delivery

3.1 Pellet Specification

Grant Spira boilers are designed to ONLY run on EN Plus Grade A1 wood pellets that comply with BS EN ISO 17225-2:2014 and meet
the following criteria. Failure to use approved pellets will invalidate the product guarantee.

Proper t y class Unit Limits as per BS EN ISO 17225-2

Origin and source 1.13 Stemwood

1.2.1 Chemically treated wood residues

Diameter (D) mm 6 ± 1

Length (L) 3.15 < L ≤ 40

Moisture (M) w-% ≤ 10

Ash (A) w-% dry ≤ 0.7

Mechanical durability
(DU)

Fines (F)

Additivies

Net calorific value (Q) MJ/kg or ≥ 16.5

Bulk density (BD)

Chlorine (Cl) w-% dry ≤ 0.02

The following terms are commonly used when describing the properties of wood pellets:

Additives Additives are used to improve the stability of the pellets. If manufactured correctly, and of a sufficiently low
moisture content, quality pellets will require no additives.

Ash Ash represents the non-combustible content of the pellet. Higher ash content reduces the calorific value of
the pellet and requires the appliance to be cleaned more frequently.

Average length To provide a predictable flow of fuel into the burner, the recommended length of a pellet is between 3.15
and 40mm.

Bulk density Bulk density is the ratio between the weight of the pellet and the amount of space they take up. A good
quality pellet will have a density of 650 kg/m

Chlorine High levels of chlorine in the flue gases emissions can give rise to corrosion.

Diameter The most common diameter is 6mm with some 8mm also available. This boiler is designed for 6mm only.

Fines Pellets are made from compressed wood. As pellets rub together they can break down slightly, producing

dust or fines. Too many fines indicate a poor quality pellet and can impede pellet flow in addition to
causing dust problems when delivering and storing the pellets.

Mechanical durability This is a measure of how stable the pellet is and how likely it is to produce fines from normal handling.
A high durability percentage is an indicator of a good quality pellet.

Moisture content Moisture affects the calorific value of the pellet. Low moisture content guarantees constant and predictable
combustion efficiency. Higher moisture contents can result in pellet breakdown.

Net Calorific Value This is the useful energy contained in a kilogram of fuel. This value is affected by the amount of non-
combustible materials (ash) and the moisture content of the pellet. Typical values range from 4.8 kWh/kg
to 5.2 kWh/kg.

Nitrogen and Sulphur High levels of Nitrogen and Sulphur in the flue gases emissions can give rise to corrosion.

b

c

d

w-% ≥ 97.5

w-% ≤ 1.0

w-% ≤ 2

Type and amount to be stated

kWh/kg ≥ 4.6

3

kg/m

≥ 600

3

.

a

Footnotes

a

Negligible levels of glue, grease
and other timber production additives
used in sawmills during production of
timber and timber product from virgin
wood are acceptable, if all chemical
parameters of the pellets are clearly
within the limits and/or concentrations
are too small to be concerned with.

b

At factory gate in bulk transport (at
time of loading) and in small (up to
20kg) and big bags (at time of packing)
or when delivering to end-user.

c

Type of additives to aid production,
delivery or combustion.

d

It is recommended actual value of
bulk density to be stated.

30

3.2 Biomass Suppliers List

The Biomass Suppliers List (BSL) is a list of suppliers of wood fuel who have been accredited as demonstrating that their fuel meets
the sustainability criteria required under the RHI.

Recipients of the Domestic RHI will be obliged to source their fuel from suppliers on the BSL unless they are supplying
themselves. To find an approved supplier in your area go to www.biomass-suppliers-list.service.gov.uk/find-a-fuel