Grant Combi 70 V3, Combi Max, Vortex Combi 26, Vortex Combi 36 User's Installation Manual

USER, INSTALLATION

and

SERVICING INSTRUCTIONS

Combi 70 V3, Combi 90 V3

Combi Max

Vortex Combi 26 and Vortex Combi 36

For use with Kerosene or Gas Oil (Vortex Combi Kerosene only)

Part No. DOC 56 Rev. 03 September 2005

This appliance is deemed a controlled service and specific regional statutory requirements

may be applicable

After installing the boiler leave these instructions with the User

For Combi 90 V3 and Combi Max Outdoor Modules installation

and wiring please refer to the separate supplement

Combi 90 V3

Combi V3, Combi Max and Vortex Combi models

2

Subject PageSection

1 Combi V3 and Combi Max user instructions .................................. 3

2 Vortex Combi user instructions ....................................................... 4

3 Combi V3, Combi Max and Vortex Combi User instructions ........ 5

4 Technical information ...................................................................... 8

5 General boiler information ............................................................... 16

6 Boiler installation ............................................................................. 34

7 Fill and vent the system ................................................................... 40

8 Commissioning ................................................................................. 41

9 Information for the user ................................................................... 43

10 Boiler servicing ................................................................................ 43

11 Boiler components ........................................................................... 47

12 Wiring diagrams ............................................................................... 49

13 Fault finding ..................................................................................... 52

14 Burner spares ................................................................................... 59

15 Health and safety information .......................................................... 61

16 EC declaration of conformity .......................................................... 62

LIST OF CONTENTS

Date: ..............................

Commissioning engineer: .............................................................................. Tel. No: ....................................

Boiler model/output: ........................................ Btu/h Fuel type: Kerosene or Gas oil

Nozzle size: .................................... Pump pressure: .................... Air setting: ...........................

Flue gas % CO2: ............................. Net flue gas temp:................ Smoke No:...........................

It is recommended that the boiler should be regularly serviced, at least once a year, and the details entered in the Boiler
Handbook by the Service Engineer.

SERVICE LOG

COMMISSIONING REPORT

3

Combi V3, Combi Max and Vortex Combi models

1 - COMBI V3 and COMBI MAX USER INSTRUCTIONS

About your Combi V3 or Combi Max boiler

1.1

Your Grant Combi boiler is fully automatic when the
Boiler On/Off switch is set to ON, and will provide
domestic hot water at mains pressure on demand and
central heating when the boiler and heating system controls
call for it.

Your boiler may be fitted with either an internal electronic
7-day timer or mechanical 24-hour timer. Alternatively,
your installer may have fitted a separate timer, in a
convenient position remote from the boiler.

Whichever type of timer is connected to your boiler, it
will allow you to set the operating times of the central
heating. Domestic hot water is available continuously,
provided the boiler is switched on, irrespective of the
settings on the timer.

To access the controls, pull off the front door from the
boiler.

1 Heating switch - When set to TIMED the boiler will

only provide central heating during the 'on' periods
set on the timer. When set to the HOT WATER
ONLY position the boiler will not provide central
heating. When set to the CONSTANT position the
boiler provides central heating continuously,
overriding all of the timer settings.

2 Boiler On/Off - This switches the boiler on and off.

Note: The timer (if fitted) will still operate with this

switch set to OFF, providing the electricity supply to
the boiler is still switched on, but the boiler will not
operate to provide domestic hot water.

3 Boiler thermostat - This control allows

adjustment of the temperature of the water leaving
the boiler to heat either the radiators or the hot
water, via the hot water heat exchanger.

The boiler thermostat has an operating range of
75°C to 85°C. For optimum hot water operation,

ensure this is set to maximum.

To ensure that the hot water performance is not
reduced first thing in the morning, or in the evening
if the heating is off through the day, set the heating
timer to switch the heating on at least 30 minutes
before hot water will normally be required in the
morning (or evening).

When setting the times for the 'on' periods it is useful
to remember that it might take up to an hour for the
house to become warm, especially in colder weather.
Also the effect of the central heating will remain for a
time when the central heating is turned off.

Do not forget that if you require central heating during an
'off' period, simply set the Heating switch to CONSTANT,
remember the switch must be reset to TIMED at a later
time for the timer to return to your pre-set periods.

The boiler will operate on either Class C2 Kerosene or
Class D Gas Oil to BS 2869:1998. Your Installer will
have informed you of the type of fuel your boiler has
been set to use and he will have marked this on the
boiler data label. You should always quote the type of
fuel you require when ordering from your supplier.

Note: Low level balanced flue installations (flue
terminal through the wall) must only be used with
Kerosene, unless the flue terminal is higher than 2.0 m
above outside ground level.

Do not wait until the fuel runs out before you order
some more. Sludge in the bottom of the tank may be
drawn into the fuel lines. If it is possible, switch off the
boiler when the new supply is delivered and leave the
fuel to settle for an hour before restarting the boiler.

Boiler controls (see Fig. A)

1.2

About your fuel

1.4

Useful tips

1.3

Combi V3, Combi Max and Vortex Combi models

4

Your Vortex Combi boiler is fully automatic once switched
on, and will provide domestic hot water at mains pressure
on demand and central heating when the boiler and
heating system controls call for it. The boiler On/Off
switch incorporates a 'mains on' neon, see Fig. B, which
lights when the boiler is switched on, but does not
necessarily indicate the burner is firing.

Your boiler may be fitted with either an internal electronic
7-day timer or mechanical 24-hour timer. Alternatively,
your installer may have fitted a separate timer, in a
convenient position remote from the boiler.

Whichever type of timer is connected to your boiler, it
will allow you to set the operating times of the central
heating. Domestic hot water is available continuously,
provided the boiler is switched on, irrespective of the
settings on the timer.

To access the controls, pull off the front door from the
boiler.

1 Store switch - Allows the primary store to be

manually switched off if hot water is not required.
With the switch set to OFF, the burner will not fire
to maintain the water temperature in the store and
the hot water (store) pump will not operate.

IMPORTANT: The boiler will not produce hot
water when the Store switch is set to OFF.

2 Heating switch - When set to TIMED, the boiler

will only provide central heating during the 'on'
periods set on the timer. When set to OFF, the
boiler will not provide central heating. When set to
CONSTANT, the boiler provides central heating
continuously, overriding all of the timer settings.

Note: Provided the Store switch is set to ON, the
boiler will provide hot water on demand
irrespective of the setting on the Heating switch
and will override the heating as required to
maintain the temperature of the store.

3 Boiler On/Off - This switches the boiler on and off.

Note: The internal timer (if fitted) will still operate

with this switch set to OFF, provided that the electricity
supply to the boiler is still switched on, but the boiler
will not operate to provide domestic hot water.

4 Boiler heating thermostat - Controls the temperature

of the water leaving the boiler to the central heating
system. Operation of this control does not affect the
temperature of the hot water flowing to the taps.

Grant Vortex Combi boilers only operate on Class C2
Kerosene to BS 2869:1998.

You should always quote the type of fuel you require
when ordering from your supplier.

Do not wait until the fuel runs out before you order
some more. Sludge in the bottom of the tank may be
drawn into the fuel lines. If it is possible, switch off the
boiler when the new supply is delivered and leave the
fuel to settle for an hour before restarting the boiler.

About your Vortex Combi boiler

2.1

Boiler controls (see Fig. B)

2.2

2 - VORTEX COMBI USER INSTRUCTIONS

About your fuel

2.3

5

Combi V3, Combi Max and Vortex Combi models

Fig. B - Boiler controls (Vortex Combi 36 shown)

Fig. A - Combi V3 and Combi Max boiler Controls

3 - COMBI V3, COMBI MAX and VORTEX COMBI USER INSTRUCTIONS

Combi V3, Combi Max and Vortex Combi models

6

1 Ensure that - There is sufficient fuel in the supply tank

and all fuel supply valves are open, the water supply is
on, the electricity supply to the boiler is off, the Boiler
On/Off switch is set to OFF, the Heating switch is set to
TIMED, the black pointer on the pressure gauge is not
below the red pointer, the room thermostat (if fitted) is
at the desired setting and the timer is correctly set.

2 Switch on the electricity supply to the boiler.

3 Set the On/Off switch to ON.

4 The boiler will light automatically to heat the water

stored in the boiler.
If the timer is set to an 'on' period the boiler will
continue to run to provide central heating. If a hot
tap is opened the boiler will supply hot water.

For short periods - Set the On/Off switch to OFF.
To restart, simply set the switch to ON.

For long periods: Set the On/Off switch to OFF and
switch off the electricity supply to the boiler. If
required, the fuel supply valve may be closed and the
water and electricity supplies turned off at the mains.

To restart, refer to the full lighting instructions above.

1 Check that the boiler On/Off switch is set to ON.

2 Check that the timer is working and is in an 'on' period.

3 Check that all thermostats are set to the desired

setting and are calling for heat.

4 Check if the burner 'Lock-out' reset button is lit. If it

is, press it to start the burner. If the burner fails to light
and goes to 'Lock-out' again, check that you have
sufficient fuel in the storage tank and that the fuel
supply valve is open.

5 Ensure that a fuse has not blown or that the

electricity supply has not failed.

6 Check to see if the overheat thermostat has operated

(see note 4 in Section 3.6).

7 Check that the black pointer on the pressure gauge

is not below the red pointer.

8 If the heating system water pressure falls below 0.2

bar the boiler low pressure cut-out switch will
activate and an amber neon on the control panel
(see Fig. A or B) will light. The system must be
recharged to between 0.5 and 1 bar. If the heating
system loses pressure on a regular basis then
contact your Installer to investigate the cause.

If the burner still fails to light after carrying out these
checks then a fault exists. Switch off the electricity
supply to the boiler and contact your Service engineer.

The boiler will supply domestic hot water whenever a
hot tap is opened, providing the Boiler On/Off switch
is set to ON.

Note: The Vortex Combi Store switch must also be set
to 'ON' for hot water to be supplied.

The flow of water from the taps (hot or cold) depends
upon the mains water pressure, and in some homes it may
not be possible to use more than one tap at the same time.

The boiler operates on a sealed central heating system which
will have been pressurised by your Installer. He will have set
the red pointer on the pressure gauge (see Fig. A or B), to
indicate the system pressure (when cold) usually between

0.5 and 1.0 bar. Do not adjust this pointer. The black pointer
indicates the actual system pressure which will increase
slightly when the boiler is operating. If the black pointer falls
below the red pointer (when the boiler is switched off and
cold), you should contact your Service Engineer to re­pressurise the system. If the system requires frequent re­pressurising, ask your Service Engineer to check the heating
system for leaks.

If the heating system water pressure falls below 0.2 bar
the boiler low pressure cut-out switch will activate and
an amber neon on the control panel (see Fig. A or B)
will light. The system must be recharged to between

0.5 and 1 bar. If the heating system loses pressure on
a regular basis then contact your Installer to
investigate the cause.

The boiler is fitted with an automatic air vent which
removes air trapped in the boiler. Any air trapped in
the radiators needs removing by venting the radiators
using the vent screw at the top of the radiators. 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.

Note: Your sealed system may incorporate a 'Top-Up'
vessel, advice on how to use it should be obtained
from your Installer.

The boiler 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 or
Service engineer.

3 - COMBI V3, COMBI MAX and VORTEX COMBI USER INSTRUCTIONS

Lighting your boiler (see Fig. A or B)

3.1

Turning off your boiler (see Fig. A or B)

3.2

Points to check if burner fails to light

3.3

Domestic hot water system

3.4

Sealed central heating system

3.5

7

Combi V3, Combi Max and Vortex Combi models

The expansion vessel air charge must be checked
annually. Failure to maintain an adequate air
charge in the vessel may invalidate the warranty.

To re-pressurise the system by adding water:

1 Only add water to the system when it is cold and

the boiler is off. Do not overfill.

2 Ensure the flexible filling loop is connected and that

the shut off valve connecting it to the boiler is open
and the double check valve at the front is closed.

A valve is open when the operating lever is in line with
the valve, and closed when it is at right angles to it.

3 Gradually open the double check valve on the front

of the filling loop until water is heard to flow.

4 Vent each radiator in turn, starting with the lowest

one in the system, to remove air.

7 Continue to fill the system until the pressure gauge

indicates the required pressure between 0.5 and

1.0 bar. Close the fill point valve.

9 Close the valves either side of the filling loop and

disconnect the loop.

The temperature of the water leaving the boiler to the
radiators can be increased by turning the boiler
(heating) thermostat (see Fig. A or B) clockwise.

With the Heating switch set to TIMED, the boiler will
provide central heating whenever the timer is in an 'on'
period and the room thermostat (if fitted) is calling for heat.

For summer time operation, when central heating is not
required, set the Heating switch (see Fig. A) to HOT
WATER ONLY, or OFF for Vortex Combi (see Fig. B).

1 Boiler controls - Refer to Section 2.2 or 3.2.

2 Pressure switch - If the heating system water pressure

falls below 0.2 bar the boiler low pressure cut-out switch
will activate and an amber light will illuminate. The
system must be recharged to between 0.5 and 1 bar. If the
heating system loses pressure on a regular basis then
contact your Installer to investigate the cause.

3 Burner Lock-out reset button - If there is a burner

malfunction, a built-in safety circuit switches the
burner off and the Lock-out reset button will light.
Usually such malfunctions are short lived and pressing
the reset button will restore normal operation.
If the burner continually goes to 'Lock-out' a fault
exists or the fuel supply is low. If you have sufficient
fuel, you will need to call your Service engineer.

4 Overheat thermostat - Your boiler is fitted with a

safety overheat thermostat which will automatically
switch off the boiler in the case of a control malfunction
causing overheating. A red neon (see Fig. A or B) will
light indicating the thermostat has operated.

If your boiler goes off and you try to light it but
nothing happens and the 'Lock-out' reset button on the
burner is not lit, the overheat thermostat has probably
operated. The boiler will not light until the thermostat
is reset. To reset, unscrew the small plastic cap (see
Fig. A or B), press the button then replace the cap.
Note: You may have to wait for the boiler to cool
down before the button will reset. If this condition
continually repeats, contact your Service engineer.

5 Ventilation - Always ensure that the boiler has

adequate ventilation. Any ventilation openings
provided by the Installer must not be obstructed.
Periodically check that they are clear.
Do not attempt to 'box in' the boiler or build a compartment
around it before consulting your Installer.
Do not place any combustible material around or
on the boiler or flue pipe.

6 Flue terminal - The flue terminal on the outside

wall must not be obstructed or damaged.
In severe conditions check that the terminal does
not become blocked by snow.

7 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 boiler
thermostat set at a low setting. For longer periods the
boiler and system should be drained. Contact your
Service engineer for draining and filling the system.

8 Cleaning and servicing - Lightly wipe over the

case with a damp cloth and a little detergent. Do
not use abrasive pads or cleaners.
You should have your boiler serviced at least once
a year to ensure safe and efficient operation.
Contact your Service engineer for further details.

9 Failure of electricity supply - If the electricity

supply fails, the boiler will not operate. It should
relight automatically when the supply is restored.
Note: The time on the internal 7-day or 24-hour
timer may need to be reset after a power failure.

The boiler requires a 230/240 V ~ 50 Hz supply. It
must be protected by a 5 Amp fuse.

Warning: This appliance must be earthed.

The section of any worktop (if fitted) above the boiler
must be removable to provide access for servicing for
the Combi 70 V3 and Vortex Combi 36.

The Combi 90 V3, Combi Max and Vortex Combi 26
boilers can be serviced from the front, but it is
preferable for any worktop above the boiler to be
removable to provide the best access for servicing.

General notes and care of your system

3.6

3 - COMBI V3, COMBI MAX and VORTEX COMBI USER INSTRUCTIONS

Electricity supply

3.7

Important

3.8

Combi V3, Combi Max and Vortex Combi models

8

22 mm copper pipe

15 mm copper pipe

15 mm copper pipe **

15 mm copper pipe

100 mm (4 in) diameter

26.5 mbar

9.5 mbar

75 to 85°C

111°C ± 3°C

1.0 bar

0.5 bar

2.5 bar

12 litres (pre-charged at 1.0 bar)

2.5 bar

3.0 litres/min (0.66 gal/min)

65°C (factory set)

8.0 bar

2.5 bar

Less than 50°C

230/240 V ~ 50 Hz Fused at 5 Amp

90 W max.

2.60 Amp

0.85 Amp

¼" BSP Male (on end of flexible fuel line)

Minimum flue draught - 8.7 N/m² (0.035 in wg)

Maximum flue draught - 37 N/m² (0.15 in wg)

* Weight includes burner but excludes flue
** 22 mm hot water pipe can be connected to the Combi Max if required.
*** Based on expansion vessel charge and initial cold system pressure of 0.5 bar.

Boiler technical data - Combi V3 and Combi Max boilers

4.1

Model

Boiler water content litre

gal

* Weight (dry) kg

lb

Max. heat input (Kerosene) kW

Btu/h

Connections: Heating flow and return

Cold water mains inlet

Domestic hot water outlet

Pressure relief valve discharge

Flue size (conventional)

Waterside resistance Flow/Return temp. diff. of 10°C

Waterside resistance Flow/Return temp. diff. of 20°C

Boiler thermostat range

Limit (safety) thermostat switch off temp.

Maximum heating system pressure (cold)

Minimum heating system pressure (cold)

Pressure relief valve

Expansion vessel

Maximum heating system volume ***

Maximum operating pressure

Minimum domestic hot water flow rate

Maximum domestic hot water temperature

Maximum mains water inlet pressure

Minimum recommended mains water inlet pressure

Max. hearth temperature

Electricity supply

Motor power

Starting current

Running current

Oil connection

Conventional flue

Combi 70 V3

80

17.6

158

348

22.0

75 000

Combi Max

40

8.8

159

350

36.8

125 500

Combi 90 V3

40

8.8

158

348

27.6

94 200

128 litres

4 - BOILER TECHNICAL INFORMATION

9

Combi V3, Combi Max and Vortex Combi models

15 mm copper pipe

22 mm plastic pipe

100 mm (4 in) diameter

65 to 80°C

111°C +0 -3°C

1.0 bar

0.5 bar

2.5 bar

2.5 bar

3.0 litres/min (0.66 gal/min)

65°C (factory set)

8.0 bar

2.5 bar

Less than 50°C

230/240 V ~ 50 Hz Fused at 5 Amp

90 W max.

2.60 Amp

0.85 Amp

¼" BSP Male (on end of flexible fuel line)

Minimum flue draught - 8.7 N/m² (0.035 in wg)

Maximum flue draught - 37 N/m² (0.15 in wg)

4 - BOILER TECHNICAL INFORMATION

* Weight includes burner but excludes flue
** Based on expansion vessel charge and initial cold system pressure of 0.5 bar

Boiler technical data - Vortex Combi boilers

4.2

Model

Boiler water content litre

(including 32.5 litre primary store) gal

* Weight (dry) kg

lb

Max. heat input (Kerosene) kW

Btu/h

Connections: Heating flow and return

Cold water mains inlet

Domestic hot water outlet

Pressure relief valve discharge

Condensate connection

Flue size (conventional)

Waterside resistance Flow/Return temp. diff. of 10°C

Waterside resistance Flow/Return temp. diff. of 20°C

Boiler thermostat range

Limit (safety) thermostat switch off temp.

Maximum heating system pressure (cold)

Minimum heating system pressure (cold)

Pressure relief valve

Expansion vessel (pre-charged at 1 bar)

Maximum heating system volume**

Maximum operating pressure

Minimum domestic hot water flow rate

Maximum domestic hot water temperature

Maximum mains water inlet pressure

Minimum recommended mains water inlet pressure

Max. hearth temperature

Electricity supply

Motor power

Starting current

Running current

Oil connection

Conventional flue

Vortex Combi 26

48.5

10.7

188

415

26

88 700

22 mm copper pipe

15 mm copper pipe

15 mm copper pipe

28.5 mbar

10.0 mbar

12 litres

128 litres

Vortex Combi 36

53.5

11.8

218

481

36

123 000

28 mm copper pipe

22 mm copper pipe

22 mm copper pipe

26.0 mbar

9.5 mbar

14 litres

148 litres

Combi V3, Combi Max and Vortex Combi models

10

Note: All boilers are despatched for use with kerosene.

Notes:

1 The data given above is approximate only. The Kerosene table is based on the boiler being used with a low level balanced flue.

2 The above settings may have to be adjusted on site for the correct operation of the burner.

3 Gas Oil is not suitable for use with a low level balanced flue, unless the flue terminal is higher than 2.0 m above outside

ground level.

4 The installer must amend the boiler data label if the type of fuel and nozzle used are changed.

5 Net flue gas temperatures given are ± 10%.

6 ** Net thermal efficiency (BSRIA).

7 Flue gas temperatures taken at combustion door test point will be approximately 25°C higher for the Combi 90 V3 and

Combi Max.

8 Flue gas temperature taken at the top of the boiler will be 20°C higher for the Combi 70 V3.

CO

2

(%)

12.0

(kW)

33.3

(Btu/h)

113 600

Heat Output

(kW)

36.8

(Btu/h)

125 500

Net Heat Input

Net eff. **

(%)

91.5

Head

type

T5

Nozzle

size

1.00/80°EH

Oil press.

(bar)

9.0

Smoke

No.

0 - 1

Fuel flow

rate (kg/h)

3.10

Net flue gas

temp. (°C)

190

Note: Burners are supplied factory set at the outputs shown.
When commissioning, or when the type of fuel is changed, the air damper must be adjusted to obtain the correct CO

2

level and the Installer must amend the data label.

4 - BOILER TECHNICAL INFORMATION

Combi V3 and Combi Max oil boilers using class C2 kerosene

4.3

Combi V3 and Combi Max oil boilers using class D gas oil

4.4

Approximate air damper settings

4.5

(kW)

32.9

(Btu/h)

112 463

Heat Output

(kW)

36.0

(Btu/h)

122 910

Net Heat Input

Net eff. **

(%)

91.5

Head

type

T5

Nozzle

size

0.75/80°S

Oil press.

(bar)

11.0

Smoke

No.

0 - 1

Net flue gas

temp. (°C)

200

Fuel flow

rate (kg/h)

3.02

Flue gas mass

flow rate (kg/h)

34.8

38.7

CO

2

(%)

11.5

12.0

(kW)

20.5

26.4

(Btu/h)

70 000

90 000

Heat Output

(kW)

22.5

27.6

(Btu/h)

76 900

94 200

Net Heat Input

Net eff. **

(%)

93.0

95.8

Head

type

LD2SX short

LD3

Nozzle

size

0.60/60°EH

0.75/60°EH

Oil press.

(bar)

8.5

9.5

Smoke

No.

0 - 1

0 - 1

Fuel flow

rate (kg/h)

1.87

2.40

Net flue gas

temp. (°C)

211

180

Combi 70 V3 and Combi 90 V3 (Riello RDB1 burner)

Flue gas mass

flow rate (kg/h)

34.8

38.7

CO

2

(%)

11.5

12.0

(kW)

20.5

26.4

(Btu/h)

70 000

90 000

Heat Output

(kW)

22.5

27.9

(Btu/h)

76 900

95 250

Net Heat Input

Net eff. **

(%)

92.0

94.6

Head

type

LD2SX short

LD3

Nozzle

size

0.40/60°S

0.60/60°S

Oil press.

(bar)

12.0

12.0

Smoke

No.

0 - 1

0 - 1

Fuel flow

rate (kg/h)

1.60

1.97

Net flue gas

temp. (°C)

200

200

Combi Max (Riello RDB2.2 burner)

Combi 70 V3 and Combi 90 V3 (Riello RDB1 burner)

Combi Max (Riello RDB2.2 burner)

Flue gas mass

flow rate (kg/h)

51.5

CO

2

(%)

12.0

Flue gas mass

flow rate (kg/h)

51.5

11

Combi V3, Combi Max and Vortex Combi models

26

36

4 - BOILER TECHNICAL INFORMATION

Notes:

1 The data given above is approximate only and is based on the boiler being used with a low level balanced flue.
2 The above settings may have to be adjusted on site for the correct operation of the burner.
3 Gas Oil is not suitable for use with a Grant Vortex Combi boiler.
4 * Net thermal efficiency.
5 The net flue gas temperatures given above are ± 10%.
6 When commissioning the air damper must be adjusted to obtain the correct CO2 level.
7 The combustion door test point may be used for CO2 and smoke readings only. Do not use this test point for temperature

or efficiency readings.

Flue gas analysis

To allow the boiler to be commissioned and serviced, the boiler is supplied with a combustion test point on the front
cleaning door. When this test point is used please note the following:

1. The test point is for CO2 and smoke readings only.

2. The boiler efficiency and temperature must be taken from the flue test point on high level, vertical and
conventional flue adaptors.

3. Concentric low level flues do not contain a test point. The temperature and efficiency readings must be taken from
the flue terminal.

Note: Vortex Combi boilers are only for use with kerosene.

Vortex Combi oil boilers using Class C2 kerosene

4.6

(kW)

26.0

36.0

(Btu/h)

88 700

123 000

101.0

101.5

Nozzle

0.75/80°EH

1.00/80°EH

Oil

press.

(bar)

8.0

9.1

Smoke

No.

0 - 1

0 - 1

Fuel flow

rate

(kg/h)

2.16

3.01

Flue gas

temp.

(°C)

75 - 80

78

CO

2

(%)

12.0

12.0

Burner

head

T2

T5

Heat Output

Net

eff *

(%)

Model

Burner

type

Riello RDB1

Riello RDB2.1

Combi V3, Combi Max and Vortex Combi models

12

Fig. 2

Water schematic of boiler - Combi V3 and Combi Max

4.8

Mains

inlet

water

Domestic

hot

water out

Blending

valve

Flow

switch

3-way

diverter

valve

Domestic
hot water

heat exchanger

Pump

Automatic

air vent

Boiler

Heating

return

Heating

flow

Expansion

vessel

Primary

store

Pressure

relief valve

Drain

cock

Pressure

switch

Check

valve

Fig. 1

Note: Water connections may be from the rear, left or right hand side. If using side exit flue, it must be on the opposite
side to the water connections.

4 - BOILER TECHNICAL INFORMATION

Boiler dimensions - Combi V3 and Combi Max

4.7

13

Combi V3, Combi Max and Vortex Combi models

4 - BOILER TECHNICAL INFORMATION

Fig. 3a - Vortex Combi 36 dimensions

Fig. 3 - Vortex Combi 26 dimensions

Boiler dimensions - Vortex Combi

4.9

Combi V3, Combi Max and Vortex Combi models

14

4 - BOILER TECHNICAL INFORMATION

Fig. 4

Water schematic of boiler - Vortex Combi

4.10

15

Combi V3, Combi Max and Vortex Combi models

White system ...... High level concentric balanced flue

kit - components available:

Extensions 225 mm, 450 mm, 950 mm and
adjustable 275 to 450 mm
45° elbow
Vertical concentric balanced flue kit
Extensions 225 mm, 450 mm, 950 mm and
adjustable 275 to 450 mm
45° elbow

The Combi V3 and Combi Max boilers are supplied
ready for use with Class C2 kerosene. If required, they
can easily be adapted for use with Class D gas oil.

Note: Only Kerosene may be used with a low level
balanced flue, unless the flue terminal is higher than

2.0 m above outside ground level.

If the fuel to be used is Gas Oil, it will be necessary to
change the burner nozzle. Refer to the Technical
Information in Section 4.3. To change the nozzle,
remove the burner from the boiler then remove the
nozzle as described in Section 10.4. The installer must
amend the boiler data label accordingly.

The Vortex Combi boilers are only suitable for use
with Kerosene.

All burners are ready to connect to a single pipe system

with a loose flexible fuel line (600 mm) and

3

/8" to 1/4"
BSP male adaptor supplied with the boiler. If required, an
additional flexible fuel line (600 mm) and 3/8" to 1/4" BSP
male adaptor are available to purchase from Grant
Engineering (UK) Limited, for two-pipe oil supply system,
Part No. RBS104.

The temperature of the water leaving the boiler to heat the
radiators is User adjustable.

To achieve the optimum hot water performance from the
Combi V3 and Combi Max, the boiler thermostat should
be set to maximum.

The setting of the boiler thermostat on the Vortex Combi
has no effect on the hot water performance.

The control panel is fitted with an ON/OFF switch,
boiler thermostat control knob and the manual reset
button for the overheat thermostat. An optional plug-in
programmer is available which allows the User to set
the operating times for central heating and hot water.
Alternatively, an external timer, located remotely from
the boiler in a convenient position for the user, may be
connected to the boiler for this purpose - the Grant TCR
kit, Part No. TCRKIT is ideal. Refer to Section 12 ­Wiring diagrams.
A programmable electronic room thermostat, Part No.
RSKIT is also available to purchase from Grant UK.

Domestic hot water is available at all times, provided
the boiler is switched on.

The Combi and Vortex Combi boilers are automatic
pressure jet oil boilers designed for use with a sealed
central heating system and will provide domestic hot
water at mains pressure.

All boilers are supplied with the control panel and burner
factory fitted.

All boilers can be connected to either a conventional
flue system or a balanced flue system, as required.

The Combi V3 and Combi Max boilers are supplied
ready to connect to a conventional flue. If the boiler is
to be used with a balanced flue, a Balanced Flue Kit is
required.

The Vortex Combi boilers are not supplied with a
flue adaptor. If a conventional flue is to be used, a
Grant conventional flue adaptor (Ref. CFCA1546)
must be ordered.

For conventional flue applications, Grant recommends
the use of the Grant 'Orange' flue system, specifically
designed for the Vortex condensing boiler. Refer to
Section 5.8 for further details.

Fitting instructions for the Low level concentric, High
level and Vertical balanced flue kits are supplied with
the kits.
Where a balanced flue system is required, the following
flue kits are available from Grant UK.
Refer to Section 5.8 for further details.

Yellow system..... Standard low level concentric

balanced flue - components available:

Low level concentric balanced flue short
Extensions 225 mm, 450 mm and 675 mm
90° extension elbow
45° extension elbow
45° elbow

Green system ...... Standard external high level/

vertical flue starter kit (room sealed) - components
available:

External high level/vertical flue starter kit short
(room sealed)
Extensions 150 mm, 250 mm, 450 mm, 950 mm
and adjustable 195 to 270 mm
45° elbow
High level terminal
Vertical terminal

5 - GENERAL BOILER INFORMATION

Boiler description

5.1

Combi V3, Combi Max and Vortex Combi models

16

Installation of a Grant Combi boiler must be in
accordance with the following recommendations:-

a Building Regulations for England and Wales,

and the Building Standards for Scotland issued
by the Department of the Environment and any
local Byelaws etc.

b Model and local Water Undertaking Byelaws.

c Applicable Control of Pollution Regulations.

d The following OFTEC requirements:-

OFS T100 Polythene oil storage tanks for

distillate fuels.

OFS T200 Fuel oil storage tanks and tank

bunds for use with distillate fuels,
lubrication oils and waste oils.

Further information may be obtained from the
OFTEC Technical Information Book 3
(Installation requirements for oil fired boilers
and oil storage tanks).

The installation should also be in accordance with the
latest edition of the following British Standard Codes
of Practice:-

BS 715 Metal flue pipes, fittings, terminals

and accessories.
BS 799:5 Oil storage tanks.
BS 1181 Clay flue linings and flue terminals.
BS 4543:3 Factory made insulated chimneys for

oil fired appliances.
BS 4876 Performance requirements for oil

burning appliances.
BS 5410:1 Code of Practice for oil firing appliances.
BS 5449 Forced circulation hot water systems.
BS 7593 Code of Practice for treatment of

water in heating systems.
BS 7671 Requirements for electrical

installations, IEE Wiring Regulations.

Failure to install and commission appliances correctly
may invalidate the boiler warranty.

Regulations to comply with

5.2

5 - GENERAL BOILER INFORMATION

IMPORTANT

Before starting any work on the boiler, or fuel supply
please read the health and safety information given in
Section 15 on page 61.

Regional statutory requirements may deem
this appliance to be a 'controlled service'. Where
this is the case, it is a legal requirement that the
appliance is installed and commissioned either
under the remit of building control or by a
'Competent person' such as a suitably qualified
Oftec registered technician.

5.3.1 Fuel storage

The tank should be positioned in accordance with the
recommendations given in BS 5410:1:1997, which gives
details of filling, maintenance and protection from fire.

A galvanised tank must not be used.

A plastic tank may be used and must comply with OFS
T100.

Note: Plastic tanks should be adequately and uniformly
supported on a smooth level surface, across their entire
base area.

5.3.2 Fuel pipes

1 Fuel supply pipes should be of copper tubing with

an internal diameter of at least 8 mm.
Galvanised pipe must not be used.

2 Flexible pipes must not be used outside the boiler

case.

3 A remote sensing fire valve must be installed in the

fuel supply line (outside) where it enters the building.
Recommendations are given in BS 5410:1:1997.

4 A metal bowl type filter with a replaceable micronic

filter must be fitted in the fuel supply line. A shut-off
valve should be fitted before the filter, to allow the
filter to be serviced.

5 A flexible fuel line, adaptor and 1/4" BSP isolation

valve are supplied loose with the boiler for the
final connection to the burner. If a two pipe system
or Tiger Loop system is used, an additional flexible
fuel line (600 mm) and 3/8" to 1/4" BSP male
adaptor are available from Grant Engineering (UK)
Limited (Part No. RBS104).

Fuel supply

5.3

17

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

6 The flexible fuel lines supplied should be inspected

annually when the boiler is serviced and replaced
at least every two years.

5.3.3 Single pipe system - (See Fig. 5)

1 Where the storage tank outlet is above the burner

the single pipe system should be used. The height
of the tank above the burner limits the length of
pipe run from the tank to the burner.

2 As supplied the burner is suitable for a single pipe

system.

5.3.4 Two pipe system - (See Fig. 6)

1 When the storage tank outlet is below the burner, the

two pipe system should be used. The pipe runs should
be as shown in Fig. 5. The return pipe should be at the
same level in the tank as the supply pipe, both being
75 to 100 mm above the base of the tank. The pipe
ends should be a sufficient distance apart so as to
prevent any sediment disturbed by the return entering
the supply pipe.

2 Avoid the bottom of the tank being more than 3 m

below the burner.

3 A non-return valve should be fitted in the supply pipe

together with the filter and fire valve. A non-return
valve should be fitted in the return pipe if the top of
the tank is above the burner.

4 To be used with a two-pipe system, the burner

must be fitted with an additional flexible fuel line
(a flexible fuel line (600 mm) and 3/8" to 1/4" BSP
male adaptor are available from Grant Engineering
(UK) Limited - Part No. RBS104).
See Section 5.3.6.

5 The pump vacuum should not exceed 0.4 bar.

Beyond this limit gas is released from the oil. A
vacuum gauge must be fitted to the fuel pump to
check the vacuum reading.

For guidance on installation of top outlet fuel tanks and
suction oil supply sizing, see OFTEC booklet T1/139.
Available at www.oftec.org.uk

Fig. 5 - Single pipe system

Combi V3, Combi Max and Vortex Combi models

18

5.3.5 Tiger Loop system - (See Figs. 7 and 8)

1 When the storage tank is below the burner, an

alternative to a two pipe system can be achieved using
the Tiger Loop oil deaerator. This effectively removes
the air from the oil supply on a single pipe lift.

2 The Tiger Loop is connected close to the boiler as

a two pipe system (omitting the non-return valve)
as shown in Fig. 7. Refer to the manufacturers
instructions supplied with the Tiger Loop. The
Tiger Loop must be mounted vertically.

5 - GENERAL BOILER INFORMATION

Note: To prevent any possibility of fuel fumes
entering the building, the Tiger Loop must be
fitted outside.

3 To be used with a Tiger Loop system, the burner

must be fitted with an additional flexible fuel line
(a flexible fuel line (600 mm) and 3/8" to 1/4" BSP
male adaptor are available to purchase from Grant
Engineering (UK) Limited - Part No. RBS104).
See Section 5.3.6.

Fig. 6 - Two pipe system

Fig. 7 - Tiger loop system

19

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

5.3.6 Two pipe oil supplies

See Fig. 9

1 The fuel pump is supplied for use with a single

pipe fuel supply system. For use on a two pipe
system, it is necessary to fit the By-pass screw (see
Fig. 9) into the tapping in the return port.

2 The By-pass screw is supplied in the boiler

accessory pack.

3 Remove the plastic burner cover (two screws).

4 Remove and discard the blanking plug from the

return connection of the pump and fit the By-pass
screw using an hexagonal key.

5 Connect the return oil flexible fuel line to the pump.

6 Connect the 3/8" to 1/4" BSP adaptor to the flexible

fuel line.

7 Flexible fuel lines and adaptors are available to

purchase from Grant Engineering (UK) Ltd.

8 The burner cover may be left off until the boiler is

commissioned.

1/4" BSP female

connections

Tiger Loop

SUPPLY

TO PUMP

RETURN

FROM PUMP

SUPPLY

FROM TANK

Fig. 8 - Tiger loop

Fig. 9 - RDB pump

1 Oil inlet connection
2 Return connection
3 By-pass screw
4 Pressure gauge connection

1

2

3

4

5

6

7

8

5 Pressure adjuster
6 Vacuum gauge connection
7 Solenoid
8 Supply to nozzle

Combi V3, Combi Max and Vortex Combi models

20

Air supply

5.5

Electricity supply

5.4

1 A 230/240 V ~ 50 Hz mains supply is required.

The boiler must be earthed.

2 The supply must be fused at 5 Amp and there must

only be one common isolator for the boiler and
control system, and it must provide complete
electrical isolation.

3 A fused double pole switch or a fused three pin

plug and shuttered outlet socket should be used for
the connection.

4 The power supply cable should be at least 0.75 mm²

PVC as specified in BS 6500, Table 16.

5 All the wiring external to the boiler must be in

accordance with the current I.E.E. Wiring Regulations.

6 Any room thermostat or frost thermostat used must

be suitable for use on mains voltage.

7 The boiler requires a permanent mains supply, do

not interrupt it with any external time control.

8 In the event of an electrical fault after installation

of the boiler, the following electrical system checks
must be carried out:- Short circuit, Polarity, Earth
continuity and Resistance to earth.

5 - GENERAL BOILER INFORMATION

See Figs. 10 and 11

A sufficient permanent air supply to the boiler should
be provided:

a For proper combustion of fuel and effective

discharge of combustion products to the open air.

b For the ventilation of any confined space in

which the boiler is installed to prevent
overheating of the boiler any equipment in and
near the boiler.

c For the satisfactory operation of any draught

stabiliser which may be fitted.

It should be both the designer's and installer's concern
that the air required for these functions be introduced
so as to cause as little discomfort as possible to the
building occupants and thus to offer them the least
temptation to obstruct the ventilators.

Further details may be obtained from BS 5410:1:1997.

Notes:

For a boiler fitted in a compartment, which is ventilated
as shown, no additional allowance is necessary.

Open flue - Extract fans, where needed, should be in
accordance with Section 4.4.7 in BS 5410 Part 1 1997.

Fig. 10 - Air supply for room sealed balanced flue boilers

21

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

Fig. 11 - Combustion and ventilation air supply for conventional flue boilers

Minimum size of air vents required - see Figs. 10 and 11

Combi Max

156 cm² (24 in²)

311 cm² (48 in²)

156 cm² (24 in²)

311 cm² (48 in²)

467 cm² (72 in²)

Vent A

Vent B

Vent C

Vent D

Vent E

Combi 70 V3

85 cm² (13 in²)

171 cm² (26 in²)

85 cm² (13 in²)

171 cm² (26 in²)

256 cm² (40 in²)

Combi 90 V3

118 cm² (18 in²)

235 cm² (36 in²)

118 cm² (18 in²)

235 cm² (36 in²)

353 cm² (55 in²)

Vortex Combi 26

116 cm² (18 in²)

231 cm² (36 in²)

116 cm² (18 in²)

231 cm² (36 in²)

347 cm² (54 in²)

Vortex Combi 36

171 cm² (27 in²)

341 cm² (53 in²)

171 cm² (27 in²)

341 cm² (53 in²)

512 cm² (80 in²)

Conventional flue system - Combi V3 and Combi Max

5.6

See Figs. 12 and 14

Grant boilers have high operating efficiencies. Care
must be taken to ensure the flue system is suitable for
the low flue gas temperatures.

1 An insulated flue terminating in a down draught

free area, i.e. at least 1 m above the point of exit
through the roof or preferably above the ridge
level, will normally provide the necessary
draught of at least 8.7 N/m2 (0.035 in wg) as
measured close to the boiler connection. If a
draught of 37 N/m2 (0.15 in wg) or more is
measured, then a draught stabiliser should be
fitted in the flue.

2 The flue terminal must be at least 600 mm from

any opening into the building, and 600 mm above
any vertical structure or wall less than a horizontal
distance of 750 mm from the terminal.

3 If an existing chimney is used, it must be lined with

a stainless steel liner for use with fuel oil. The top
and bottom of the annular space must be sealed and
the void filled with a suitable insulating material to
reduce cooling of the flue gases.

4 If a rigid flue is used either internally or externally,

it must be of the twin wall type with a stainless
steel inner skin suitably insulated and weather
proofed.

5 The internal flue diameter for all models must

be 100 mm (4 in).

6 The flue must be run upwards following as near a

vertical route as possible. Horizontal runs must be
avoided and no bends should have an angle of more than
45° from the vertical. There should be at least 600 mm
of vertical flue above the boiler before the first bend.

Combi V3, Combi Max and Vortex Combi models

22

7 A sealed cleaning door must be provided near the

base of the flue.

8 The exposed flue pipe between the boiler and the

chimney must not be of an asbestos material and
aluminium must not be used in any part of the flue.

9 If the draught conditions are satisfactory, the flue

should terminate with a standard cowl. Where the
flue cannot terminate above the ridge of the roof,
use an 'OH' or similar type cowl where
downdraughting occurs.
Ridge vent terminals must not be used.

10 Refer to the locally applicable Building

Regulations, BS 5410:1 and OFTEC Installation
Requirements (Books 2 and 3) for further guidance
on conventional flue systems.

11 To allow for flue gas analysis and combustion

testing, a test point is provided in the boiler
cleaning door - Combi 90 V3 and Combi Max ­and on top of the Combi 70 V3 boiler .

Conventional flue system - Vortex Combi

5.7

Fig. 12 - Typical conventional flue with brick chimney

5 - GENERAL BOILER INFORMATION

Under no circumstances can Grant Vortex Combi boilers be installed with existing flue systems. Only flue
systems and components suitable for wet flues should be used.
Failure to install the correct type of flue system will invalidate the warranty.

See Figs. 13 and 14

Care must be taken to ensure the flue system is suitable
for the very low flue gas temperatures and condensate in
the flue gases - suitable conventional flue systems (Orange
system) are available from Grant UK - see Fig. 13 and
page 24.

1 The flue must terminate in a down draught free area,

i.e. at least 600 mm above the point of exit through the
roof or preferably above the ridge level.

2 The condensate may be allowed to run back into

the boiler. A condensate drain at the base of the
flue system is not required.

23

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

3 The flue terminal must be at least 600 mm from

any opening into the building, and 600 mm above
any vertical structure or wall less than a horizontal
distance of 750 mm from the terminal. See Fig. 13.

4 If an existing chimney is used, it must be lined with

a smooth bore stainless steel liner for use with oil
fired condensing boilers. The top and bottom of the
annular space must be sealed.

5 If a rigid flue is used externally, it must be of the twin wall

type incorporating seals, must have a stainless steel inner
skin and be suitably insulated and weather proofed.

Fig. 13 - Vortex Combi typical conventional flue with brick chimney

6 The internal flue diameter for all models must be

100 mm (4 in).

7 Twin wall flues are recommended for externally

run flues to reduce the possibility of the condensate
freezing in the flue.

8 The exposed flue pipe between the boiler and the

chimney must not be of an asbestos material and
aluminium must not be used in any part of the flue. Only
stainless steel should be used.

9 If the draught conditions are satisfactory, the flue

should terminate with a standard cowl.

Combi V3, Combi Max and Vortex Combi models

24

10 Refer to the locally applicable Building

Regulations, BS 5410:1 and OFTEC Installation
Requirements (Books 2 and 3) for further guidance
on conventional flue systems.

It is important to ensure that the flue system is sealed
and that condensate cannot escape. Up to 1.5 l/h of
condensate can be produced in a conventional flue
system.

Only use flue systems suitable for oil fired condensing
boilers.

Do not use fire cement. The use of high temperature
silicone sealants is recommended.

Grant EZ-Fit Flexi Pack conventional flue system
(Orange System) - See Fig. 13

A range of Flexi pack conventional flue lining kits are
available from Grant UK. The packs have been
specifically produced for Grant Vortex Combi
condensing boilers.

Contents of Grant EZ-Fit Flexi Pack

The pack includes a smooth bore flexible stainless steel
100 mm diameter flue liner with chimney top clamping
plate, a rigid to flexi adaptor for the top of the liner, a rigid
to flexi adaptor for the bottom of the liner, a terminal, a
boiler connector (CFCA15/46) suitable for all Grant
Vortex condensing boilers and a connector from the
boiler adaptor to rigid flue system.

5 - GENERAL BOILER INFORMATION

Apart from a conventional flue, several balanced flue
options are available for use with Grant Combi boilers.
All are suitable for use with Class C2 kerosene and Class
D Gas oil (kerosene only for the Vortex Combi).

When using Gas oil, the flue must terminate a
minimum of 2 metres above outside ground level.

Note: None of the flue sections in the following

system can be cut.

1 Low level horizontal balanced flue (Yellow system)

Available in Short (for single thickness brick walls)
and Standard kits.

Extensions are available which extend the flue by
225 mm, 450 mm or 675 mm. 90° and 45° elbows
are also available.

The maximum flue length - from the centre of the
boiler flue outlet to the outer face of the wall - is 2
metres (with or without elbows included). No more
than 2 x 45° or 1 x 90° elbow should be fitted per
system.

IMPORTANT: For Vortex Combi boilers with the
flue to the left hand side - leave a minimum gap of
150 mm between the side of the boiler and the wall
to accommodate the condensate trap.

2 High level (horizontal) balanced flue (White

system)

Allows the flue to rise vertically within the building
before exiting through the wall horizontally.

The maximum flue length - from the top of the
boiler flue outlet to the outer face of the wall - is 4
metres for the Combi V3 and Combi Max and 6
metres for the Vortex Combi.

Extensions are available which extend the flue by
225 mm, 450 mm or 950 mm. An adjustable
extension of 275 to 450 mm is also available.

A 45° elbow is also available. No more than 2 x 45°
elbows should be fitted per system. Each elbow
reduces the overall maximum length of the system by
1 metre.

3 Vertical balanced flue (White system)

Allows the flue to rise vertically from the boiler to
exit through the roof.

The maximum flue length - from the top of the
boiler flue outlet to the terminal - is 6 metres for
the Combi V3 and Combi Max and 8 metres for the
Vortex Combi.

Part No.

GFKIT6

GFKIT8

GFKIT10

GFKIT11

Description - Flexi Pack

Flexi pack with 6 m liner, terminal and adaptors

Flexi pack with 8 m liner, terminal and adaptors

Flexi pack with 10 m liner, terminal and adaptors

Flexi pack with 11 m liner, terminal and adaptors

Part No.

WX150/200

WX250/200

WX450/200

WX950/200

WXA250/200

WE45/200

Description - Extensions

150 mm extension with locking band

250 mm extension with locking band

450 mm extension with locking band

950 mm extension with locking band

195-270 mm adjustable extension with locking band

45° elbow with locking band

Extensions

A range of white powder coated twin wall extensions
are available to connect the boiler to the flexible liner.
The external diameter of the extensions is 150 mm.
Extensions are supplied with locking bands.

Flue extensions cannot be cut.

An adjustable extension is available. 45° elbows are
also available.
The rigid flue between the boiler and flexible flue liner
should incorporate an adjustable section to allow
inspection and cleaning of the flue system.

Balanced flue options

5.8

25

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

Extensions are available which extend the flue by
225 mm, 450 mm or 950 mm. An adjustable
extension of 275 to 450 mm is also available.

A 45° elbow is also available. No more than 2 x
45° elbows should be fitted per system. Each elbow
reduces the overall maximum length of the system
by 1 metre.

4 External balanced flue (Green system)

Where it is not practical to use a low level (Yellow
system) or internal high level/vertical (White
system) balanced flue, the boiler can be fitted with
an external vertical/high level flue (Green system).
See Fig. 14.

The Starter kit fits to the boiler in the same way as a
low level balanced flue (Yellow system) and the
external Tee allows the connection of a twin wall
insulated flue pipe and a combustion air inlet ­providing a room sealed flue system. The external
system can terminate at either high level or vertically
(above roof level) as required. See Fig. 14.

The minimum dimensions for locating the terminal
from building features (windows, doors, etc.) are
shown in Fig. 15.

If the flue terminal is fitted less than 2 metres above a
surface to which people have access, the terminal must
be protected by a guard. The guard must be fitted
centrally over the flue terminal and securely fixed to
the wall.

The low level balanced flue (Yellow system) is
supplied with a stainless steel guard. This must be
fitted in all circumstances to prevent objects from
entering the flue outlet.

The terminal must be positioned so as to avoid
products of combustion accumulating in stagnant
pockets around the buildings or entering into
buildings. Care should be taken that the plume from
condensed flue gases does not cause a nuisance.

The following external flue (Green system) components
are available from Grant UK

All models over 26 kW

Item

Starter kit - standard

Starter kit - short

150 mm extension

250 mm extension

450 mm extension

950 mm extension

195-270 mm adjustable extension

45° elbow

High level terminal

Vertical terminal

Wall bracket - standard

Wall bracket - extended

Part No.

GK200

GK200S

GX150/200

GX250/200

GX450/200

GX950/200

GXA250/200

GE45/200

GTH200

GTV200

GWB200

GEB200

All models upto 26 kW

Item

Starter kit - standard

Starter kit - short

150 mm extension

250 mm extension

450 mm extension

950 mm extension

195-270 mm adjustable extension

45° elbow

High level terminal

Vertical terminal

Wall bracket - standard

Wall bracket - extended

Part No.

GK90

GK90S

GX150/90

GX250/90

GX450/90

GX950/90

GXA250/90

GE45/90

GTH90

GTV90

GWB90

GEB90

Combi V3, Combi Max and Vortex Combi models

26

5 - GENERAL BOILER INFORMATION

Fig. 14 - External flue (Green system)

27

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

Fig. 15 - Clearances for Balanced flues

Notes: * 75 mm with protection.

** 300 mm British Standards

Distances measured to rim of terminal.

Clearances recommended by Grant
Engineering (UK) Limited in accordance with
British Standards and Building Regulations.

A Below a gutter or sanitary pipework

B Horizontal from an opening, air brick or window

C Above ground or balcony level

D Below eaves or balcony

E From an internal or external corner

F From a terminal facing the terminal

G From a surface facing the terminal

H Vertical from terminals on the same wall

I Horizontal from terminals on the same wall

J Below an opening, air brick, window etc.

K From vertical sanitary pipework

L Vertical flue from a wall

M From an oil storage tank

Min. distance (mm)Terminal position

* 600

600

**300

*600

**300

1200

600

1500

750

600

300

600

1800

Notes:1 An opening means an openable

element, such as an openable
window, or a permanent opening
such as a permanently open air vent.

2 Notwithstanding the dimensions

given, a terminal should be at least
300 mm from combustible material,
e.g. a window frame.

3 A way of providing protection of

combustible material would be to fit
a heat shield at least 750 mm wide.

Frost protection

5.9

For additional protection of either the entire heating
system, or the boiler and localised pipework, it is
recommended that a frost thermostat be installed.
Refer to Section 6.7 for connection details.

To protect the heating system the frost thermostat
should be sited within the house in such a place that it
can detect any rise and fall in the ambient air
temperature, i.e. in a room with a radiator.

Where the frost thermostat is installed outside the
house (to protect a boiler installed in an external boiler
room or garage) or in an attic, it is recommended that
it be used in conjunction with a pipe thermostat to
avoid unnecessary and wasteful overheating of the
property. The pipe thermostat should be located on the
boiler return pipe, and set to operate at 25°C. Refer to
Section 12 for connection details.

Combi V3, Combi Max and Vortex Combi models

28

1 The boiler must stand on a surface that is firm and

level. It does not require a special hearth as the
temperature of the boiler base is less than 50°C.

2 Sufficient clearance must be allowed at the front of the

boiler to remove the burner and baffles for servicing.

3 The Combi 70 V3 and Vortex Combi 36 require a

removable section of worktop (if fitted) above the
boiler to provide access to components on top of
the boiler and for servicing.
The Combi 90 V3, Combi Max and Vortex
Combi 26 boilers can be serviced from the front,
but it is preferable for any worktop above the
boiler to be removable.

4 Vortex Combi - Care should be taken when siting

the condensate trap. See Section 5.17.

Note: Water connections may be from the rear, left
or right hand side. If using low level side exit flue,
connections must be on the opposite side to the flue.

Combi V3 and Combi Max:

Four push-fit elbows are supplied with the boiler for
connection of the heating flow and return pipes (22
mm), cold water mains inlet pipe (15 mm) and
domestic hot water outlet pipe (15 mm) to the four
open pipe ends in the boiler. See Fig. 22.

The heating flow and return connections have been
fitted with isolation valves for maintenance.

Vortex Combi:

Flow and return connections - All models are

supplied with a push-fit elbow connection for the
heating flow and return - 22 mm (Vortex Combi 26) or
28 mm (Vortex Combi 36).

Hot water connections - All models are supplied with
push-fit elbow connections for the cold water mains inlet
pipe and hot water outlet pipe. These are 15 mm for the
Vortex Combi 26 and 22 mm for the Vortex Combi 36.

5 - GENERAL BOILER INFORMATION

Boiler location

5.10

IMPORTANT: All pipes to be fitted into the push-fit
connectors provided should be cut using a pipe slicer or
pipe cutter - to leave the pipe ends with a slight radius and
free from any burrs or sharp edges. Pipes to be used with
these fittings should not be cut square using a hacksaw.

All models:

1 A 15 mm discharge pipe must be connected to the

safety valve outlet connection. The pipework between
the safety valve and the boiler must be unrestricted,
i.e. no valves. The discharge pipe should be run to the
outside of the building and terminate so that it cannot
cause injury to persons or property.

2 A drain tap is provided at the bottom on the front

of the boiler (and also on the hot water store on the
Vortex Combi).

To avoid the danger of dirt and foreign matter entering
the boiler the complete heating system should be
thoroughly flushed out - before the boiler is connected
and then again after the system has been heated and is
still hot. This is especially important where the boiler
is used on an old system.

For optimum performance after installation, this boiler
and its associated central heating system must be flushed
in accordance with the guidelines given in BS 7593:1992
'Treatment of water in domestic hot water central heating
systems'.

This must involve the use of a proprietary cleaner,
such as BetzDearborn's Sentinel X300 or X400, or
Fernox Restorer. Full instructions are supplied with the
products, but for immediate information, please
contact BetzDearborn on 0151 4209563 or Fernox on
0179 9550811.

For Long term protection against corrosion and scale,
after flushing, it is recommended that an inhibitor such as
Betzdearborn's Sentinel X100 or Fernox MB-1 is dosed
in accordance with the guidelines given in BS 7593:1992.

Failure to implement the guidelines will invalidate the
warranty.

Water connections

5.11

29

Combi V3, Combi Max and Vortex Combi models

See Fig. 16

1 The boilers are only suitable for use with a sealed

system complying with the requirements of BS 5449.
The maximum temperature of the central heating
water is 85°C for the Combi V3 and Combi Max
and 80°C for the Vortex Combi models.
Design notes - when designing the system, the
pump head, expansion vessel size, radiator mean
temperature, etc. must all be taken into account.

2 The boilers are supplied with the following items

factory fitted:­a 12 litre diaphragm expansion vessel complying

with BS 4814, pre-charged at 1.0 bar. A 14 litre
vessel is fitted in the Vortex Combi 36 model.

b System pressure gauge, with an operating range

of 1 to 4 bar.

c Pressure relief safety valve complying with

BS 6759 and set to operate at 2.5 bar. The discharge
pipe must be routed clear of the boiler to a drain,
in such a manner that it can be seen, but cannot
cause injury to persons or property.

d Automatic air vent, fitted to the top of the

boiler, ensures the boiler is vented.

e Filling loop. This must be isolated and

disconnected after filling the system.

3 Refer to Sections 4.1 or 4.2 for system volume and

BS 7074: for further guidance.
Refer to Section 6.8 for further details of the
expansion vessel.

5 - GENERAL BOILER INFORMATION

4 The system design pressure (cold) should be

between 0.5 and 1.0 bar. This pressure is
equivalent to the maximum static head (see Fig.

16) in bar + 0.3 (1 bar = 10.2 metres of water).

5 If thermostatic radiator valves are fitted to all

radiators, a system by-pass must be fitted. The by­pass must be an automatic type.

6 Provision should be made to replace water lost

from the system. This may be done manually
(where allowed by the local Water Undertaking)
using the filling loop arrangement supplied with the
boiler.

7 Filling of the system must be carried out in a

manner approved by the local Water Undertaking.
Where allowed, the system may be filled via the
filling loop supplied (the loop arrangement
includes a double check valve assembly).

8 All fittings used in the system must be able to

withstand pressures up to 3 bar.

9 Radiator valves must comply with the requirements

of BS 2767(10):1972.

10 One or more drain taps (to BS 2879) must be used

to allow the system to be completely drained.

11 The expansion vessel is connected via a flexible

hose to allow it to be moved to gain access to the
baffle cleaning cover. When replacing the vessel,
care should be taken to ensure that the flexible
connecting hose is not twisted.

Fig. 16 - Sealed system

If thermostatic radiator valves are fitted, the
system must incorporate an adequate by-pass.

Sealed central heating system

5.12

Combi V3, Combi Max and Vortex Combi models

30

Note: Hard Water
A water hardness test kit is supplied with the
boiler. Should the total hardness of the water
supply exceed 125 ppm, an in-line scale inhibitor
should be fitted in the cold water supply to the
boiler. Consult the local Water Undertaking if in
doubt.

Important: Do not immerse the test strip in running

water and avoid contact.

Fill a clean container with a sample of water from the
mains cold water supply to the boiler.

Immerse the test strip in the water for approximately
one second, ensuring that all the test zones are fully
wetted.

Shake off the surplus water and wait for one minute.

Assess the colouration of the test zones using the
following chart.

Domestic hot water system

5.13

To use the water hardness kit

5.14

Green areas

4

3

2

1

0

Violet areas

0

1

2

3

4

Hardness

very soft

soft

medium

hard

very hard

Total hardness mg/l (ppm)

<50 mg/l calcium carbonate

>70 mg/l calcium carbonate

>125 mg/l calcium carbonate

>250 mg/l calcium carbonate

>370 mg/l calcium carbonate

Note: (1 mg/l = 1 ppm (part per million)

1 To maintain a longer and more consistent hot water

temperature, a flow restrictor is factory fitted to all
models except the Combi Max and Vortex Combi
36, to limit the flow rate to approximately 15 litres/
min. The flow restrictor is located in the outlet side
of the cold water inlet isolating valve.

2 The incoming mains water pressure should be

between 1 and 8 bar to ensure efficient operation.
If the pressure is above 8 bar a pressure reducing
valve must be fitted.

The boiler may still operate down to a pressure of

1.0 bar but with a reduced flow rate. The minimum
flow rate needed for the flow switch to operate is 3
litres/min.

3 To ensure economic use, the pipe runs between the

boiler and hot taps should be as short as possible
and in 15 mm copper pipe or 22 mm for the Combi
Max and Vortex Combi 36 only. Where possible
the pipework should be insulated to reduce heat
loss.

4 All taps and mixing valves used in the domestic hot

water system must be suitable for operating at a
mains pressure of up to 8 bar.

5 If required, a shower may be fitted in the domestic hot

water system. It is recommended that thermostatically
controlled shower valves are used to protect against a
flow of water at too high a temperature. If a fixed
head type shower is used, no anti-syphonage devices
are required. If a loose or flexible head type shower is
used, it must be arranged so that the head cannot fall
closer than 25 mm above the top of the bath, thereby
preventing immersion in the bath water. If this is not
practicable, an anti-syphonage device must be fitted
at the point of the flexible hose connection.

6 The supply of hot and cold mains water direct to a

bidet is allowed (subject to local Water
Undertaking requirements) provided that the bidet
is of the over-rim flushing type. The outlets should
be shrouded and unable to have a temporary hand
held spray attached. Arrangements for anti­syphonage are not necessary.

7 Before the mains water supply pipe is connected to the

boiler, it should be thoroughly flushed out to avoid the
danger of dirt or foreign matter entering the boiler.

8 The mains water connection to the boiler must be

the first connection from the mains supply.

5 - GENERAL BOILER INFORMATION

If the hardness reading is found to be in the medium to
very hard range (the shaded area), it is essential that some
form of water conditioner or softener is fitted to reduce
scale formation within the combination boiler. Failure to
do so may invalidate both the manufacturers warranty
and any extended warranty covering the appliance.

The water conditioner or softener should be fitted to
the cold water supply serving the appliance and in
accordance with the manufacturers instructions. Grant
Engineering (UK) Ltd. cannot be held responsible for
any damage or misuse caused by the fitting of any
water conditioning device.

Please protect the domestic hot water system from
harmful effects of scale.
Problems caused by the build-up of limescale are
not covered under the terms of the warranty.

31

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

See Fig. 17

On underfloor systems it is essential that the return is
pre-heated by mixing flow water into the return before
it enters the boiler. To prevent internal corrosion of the
boiler water jacket, the return water temperature must
be maintained above 55°C for the Combi V3 and
Combi Max and 40°C for the Vortex Combi

General - Grant boilers are compatible with both
copper and plastic pipe. Where plastic pipe is used it
must be of the oxygen barrier type and be of the
correct class (to BS 7291:Part 1:1990) for the
application concerned.

IMPORTANT: The first metre of pipework
connected to both the heating flow and return
connections of the boiler must be made in copper.

If plastic pipe is to be used, the installer must check with
the plastic pipe manufacturer that the pipe to be used is
suitable for the temperature and pressures concerned.
Pipe must be Class S to BS 7291: Part 1:1990.

The boiler is fitted with a low-pressure switch to shut
off power to the boiler if the system pressure drops
below 0.2 bar.

Underfloor systems (see Section 5.15) - Plastic pipe
may be used on Underfloor systems where the plastic
pipe is fitted after the thermostatic mixing valve.
Copper tube must be used for at least the first metre of
flow and return primary pipework between the boiler
and the underfloor mixing/blending valves.

Fig. 17 - Underfloor system

Underfloor heating systems

5.15

Pipework materials

5.16

Condensate disposal - Vortex Combi

5.17

When in condensing mode the Vortex Combi boiler
produces condensate from the water vapour in the flue
gases. Provision must be made for the safe and
effective removal of the condensate.

Condensate can be disposed either internally - into an
internal domestic waste system or directly into the soil
stack, or externally - to an external soil stack, gully,
hopper or soakaway.

It should be noted that connection of a condensate pipe to the
drain may be subject to local Building Control requirements.

Pipework

Condensate disposal pipework must be plastic (plastic
waste pipe is suitable). Copper or steel pipe is NOT
suitable and should NOT be used.

The internal diameter of condensate disposal pipes
should not be less than 20 mm - e.g. 22 mm plastic
plumbing pipe or 19 mm (¾") plastic overflow pipe.

Condensate disposal pipes must be fitted with a fall of

2.5° (1:20).

For boilers installed where it is not possible for the pipe
to fall towards the point of discharge - either internally
into a waste system or externally to a gulley - e.g. in a
basement, it will be necessary to use a condensate pump.

Condensate disposal pipes should be kept as short as
possible and the number of bends kept to a minimum.
Pipes should be adequately fixed to prevent sagging,
i.e. at no more than 0.5 metre intervals.

Ideally, external pipework, or pipework in unheated
areas such as garages, should be avoided. If
unavoidable, external pipework should be kept as short
as possible (less than 3 metres) and 32 mm waste pipe
used to minimise the risk of freezing.

The number of bends, fittings and joints on external
pipes should be kept to a minimum to reduce the risk
of trapping condensate.

Condensate trap

Condensate disposal pipes MUST be fitted with a trap

- whether they are connected internally or externally.

Vortex Combi boilers are supplied with a condensate
trap to provide the required 75 mm water seal in the
condensate discharge pipe from the boiler. This trap
incorporates a float (which will create a seal when the
trap is empty) and an overflow warning outlet (fitted
with a rubber bung), See Fig. 18.

Combi V3, Combi Max and Vortex Combi models

32

Method of operation

5.18

5 - GENERAL BOILER INFORMATION

Fig. 18 - Condensate trap

The trap must be located internally in an accessible
position to allow for routine maintenance. The
mounting bracket supplied with the trap MUST be
used - the trap should NOT be supported by the
condensate pipework only.

A 22 mm push-fit plastic plumbing connector is
supplied with the boiler to connect the plastic pipe to
the stainless steel condensate outlet pipe - on the left
hand side of the boiler.

Use 22 mm plastic plumbing pipe between the boiler
and the inlet of the trap. Either 22 mm plastic
plumbing pipe or 19 mm (¾") overflow pipe can be
used from the outlet of the trap.

Note: Due to the wall thickness of plastic plumbing pipe, it
may be necessary to chamfer the internal edge of the pipe
before fitting it onto the spigot in the outlet of the trap.

If connecting the condensate discharge internally - into
a waste system or soil stack - the bung must be fitted in
the overflow outlet of the trap.

Fig. 19 - Purpose made condensate soakaway

On external discharge systems to a gully or soakaway,
the bung should be removed from the overflow outlet.
If connected to an external soil stack, the bung must be
fitted on the trap.

If there is any discharge of condensate from the
overflow outlet, this could indicate a blockage
(possibly due to freezing). Turn off the boiler and
contact your service engineer.

Care should be taken when siting the trap such that the
overflow outlet is readily visible and that any condensate
overflowing from the outlet cannot cause either a hazard to
persons or damage to surrounding property or equipment.

IMPORTANT: The trap MUST be checked at regular
intervals (e.g. on every annual service) and cleaned as
necessary to ensure that it is clear and able to operate.

It is recommended that, if there is access to the left hand
side of the boiler, the condensate pipe be connected to the
boiler using a 'tee-piece' and cap to form a 'rodding eye'

- to allow cleaning inside the back of the condensing heat
exchanger via the boiler condensate outlet.

Once the boiler is switched on it will always provide
domestic hot water upon demand. The timer only
controls the operating times of the central heating.
When central heating is not required, the timer switch
should be set to OFF.

33

Combi V3, Combi Max and Vortex Combi models

5 - GENERAL BOILER INFORMATION

Domestic hot water supply always takes priority over
central heating. If a demand for hot water occurs
during a period of central heating, the boiler mode will
automatically change to provide hot water until the
demand ceases. This interruption in the central heating
only lasts for as long as hot water is required and
should not be noticed by the User.

Central Heating Mode - If there is a call for heat, i.e. the
timer and room thermostat (if fitted) are calling for heat,
the pump will start to circulate the central heating water
and the burner will light. When the temperature in the
boiler reaches that set on the boiler thermostat, the burner
is turned off. The pump continues to run, circulating
water around the system, for as long as both the timer and
room thermostat (if fitted) are calling for heat. As the
heating system water cools, the temperature drop is
detected by the boiler thermostat and the burner is
automatically restarted for the cycle to continue until
either the timer or room thermostat stops calling for heat.
The burner and pump are then turned off.

Domestic Hot Water Mode (Combi V3 and Combi
Max) - When a demand for hot water (by opening a

hot tap, etc.) is sensed by the diverter valve flow
switches, the pump starts and the water in the boiler is
diverted through the domestic hot water plate heat
exchanger, heating the incoming mains water. The hot
water produced is mixed in the thermostatic blending
valve with incoming mains water to automatically
ensure that the temperature does not exceed 65°C.

When the hot tap is closed and the diverter valve flow
switches sense that hot water is no longer required, if the
timer switch is set to either TIMED or CONSTANT, the
boiler will return to the central heating mode, with the
pump and burner running. If the switch is set to HOT
WATER ONLY, the pump is turned off but the burner
will continue to run for a short period until the water in the
boiler reaches the required temperature ready for another
hot water operation.

Domestic Hot Water Mode (Vortex Combi) - When a
demand for hot water (by opening a hot tap, etc.) is sensed
by the flow switch, the Hot Water pump starts and
circulates water from the store through the hot water plate
heat exchanger heating the incoming mains water.

The hot water produced is mixed in the thermostatic
blending valve with incoming mains water to automatically
ensure the water temperature does not exceed 65°C.

When the hot tap is closed and the flow switch senses that
hot water is no longer required, the Hot Water pump will
continue to run and the burner continues to fire until the
primary store temperature control is satisfied.

If the Heating switch is set to either TIMED or
CONSTANT, the boiler will return to the central
heating mode, with the Heating pump and burner
running. Note - As the temperature of the boiler is now
higher than the boiler thermostat setting the burner
may not fire immediately, but only after the flow
temperature has fallen to below the thermostat setting.

If the Heating switch is set to OFF, or the timer is in an
OFF setting, the Heating pump will not operate.

For optimum performance the thermostatic blending
valve has been factory set to provide a hot water
temperature of approximately 50°C.

If the water in the boiler is already up to temperature
when a hot tap is opened, there will be a delay before
the burner fires to maintain the hot water temperature
in the boiler (to heat the hot water).

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 in
the heat exchanger. This superheated steam contains
sensible heat (available heat) and latent heat (heat
locked up in the flue gas). A conventional boiler
cannot recover any of the latent heat and this energy is
lost to the atmosphere through the flue.

The Vortex Combi condensing boilers contain an extra
heat exchanger which is designed to recover the latent
heat normally lost by conventional boilers. This is done
by cooling the flue gases to below 55°C, thus extracting
more sensible heat and some of the latent heat.

To ensure maximum efficiency, the boiler return
temperature should be 55°C or less, this will enable the
latent heat to be condensed out of the flue gases. The
boiler will achieve nett thermal efficiencies of 100%.

To achieve maximum performance from a Vortex Combi
boiler, it is recommended that the heating system is
designed so that a temperature differential of 20°C
between the flow and return is maintained.

The boiler will however still operate at extremely high
efficiencies even when it is not in condensing mode and
therefore is suitable for fitting to an existing heating
system without alteration to the radiator sizes. The boiler
is capable of a maximum flow temperature of 80°C.

To achieve the maximum efficiencies possible from a
Vortex boiler, the heating system should be designed
to the following parameters:

How Vortex condensing boilers work

5.19

5.20

Vortex heating system design considerations

Combi V3, Combi Max and Vortex Combi models

34

Radiators:-

Flow temperature 70°C
Return temperature 50°C
Differential 20°C

Underfloor:-

Flow temperature 50°C
Return temperature 40°C
Differential 10°C

1 Carefully remove the packaging from the boiler

and remove it from the transit pallet.

2 Pull off the boiler front panel and remove the

literature pack.

3 Lift off the two parts of the case top and remove

the water connecting fittings.

See Fig. 20 and 20a

If the boiler is to be used with a low level balanced
flue (Yellow system) make the hole in the wall for the
flue as shown in Fig. 20a.

Note: Dimension B given in Fig. 20a includes an
extra 10 mm over the size of the terminal to provide
clearance for fitting.

5 - GENERAL BOILER INFORMATION

Fig. 20a - Low level balanced flue (Yellow system) and Starter kit (Green system)

Fig. 20 - Low level balanced flue

1 Size radiators with a mean water temperature of 60°C.

2 Design system controls with programmable room

thermostats or use weather compensating controls
to maintain return temperatures below 55°C.

The boiler should not be allowed to operate with
return temperatures of less than 40°C when the
system is up to operating temperature.

6 - BOILER INSTALLATION

Combi V3 and Combi Max

Vortex Combi 26

Vortex Combi 36

A

756

768

780

Dimension (mm)Model

B dia

127

127

162

C

110

115

105

Unpack the boiler

6.1

Low level balanced flue

6.2

35

Combi V3, Combi Max and Vortex Combi models

See Fig. 21 and 21a

If the boiler is to be used with the high level balanced
flue (White system) make the hole in the wall as shown
in Fig. 21a.

Note: Dimension B given in Fig. 21a includes an
extra 10 mm over the size of the terminal to provide
clearance for fitting.

Fitting instructions for the high level balanced flue and
vertical balanced flue are supplied with the flue kits.

Adjustable sections: The adjustable extensions are
telescopic. The wall terminal section is adjustable and
is suitable for a wall thickness of 215 mm to 450 mm.
Simply adjust to the required length using a twisting
motion. The outer pipes must overlap by a minimum
of 25 mm.

High level and vertical balanced flue

6.3

6 - BOILER INSTALLATION

Fig. 21a - High level balanced flue (White system)

Fig. 21 - High level balanced flue

Combi V3 and Combi Max

Vortex Combi 26

Vortex Combi 36

1700 - 2100

1715 - 2115

1700 2020

Dimension (mm)Model

B dia

175

175

200

C

110

115

105

A

1200*

1215*

1280*

*Dimension A for Starter section and elbow/terminal only

Combi V3, Combi Max and Vortex Combi models

36

Fig. 22a Vortex Combi pipe positions

6 - BOILER INSTALLATION

Combi V3 and Combi Max water connections

Note: Water connections may be from the rear, left or
right hand side. If using low level side exit flue, the flue
must be on the opposite side to the water connections.

1 If required, for easier access, the case bracing bracket

may be temporarily removed. Remove the four screws
securing the bracing bracket and lift it out.

2 Removable plates are provided on both side panels

for pipe entry.

3 Fit the four push-fit elbow connectors onto the

open pipe ends. See Fig. 22. Connect the pipework
(not supplied with the boiler) to the elbows.

4 Balanced flue models - proceed with the flue installation

as described in the separate fitting instructions.

5 Conventional flue models - proceed with the flue

connection as described in Section 6.6.

6 The safety valve discharge pipe must be routed

clear of the boiler to outside, to discharge in such a
manner that it can be seen but cannot cause injury
or damage to persons or property.

7 Do not turn on the mains water supply at this stage.

Vortex Combi water connections

Flow and return pipework can be routed to either side of
the boiler, dependant on the flue system used, from the
push-fit elbows (supplied) on the flow and return
connection. Refer to Section 5.11 - Water connections.

Make the water connections

6.4

Fig. 22 - Combi V3 and Combi Max pipe positions

Holes are provided in the rear of the casing side panels to
allow the condensate pipe to be run through the back of the
boiler. It will be necessary to remove the back panel from the
boiler casing to fit this pipework, and to refit the panel before
placing the boiler in its final position.

If access will be restricted, make any connections to
the boiler before placing it in its final position.

If using a balanced flue system - Install the balanced
flue system before connecting the heating system
pipework to the boiler.

37

Combi V3, Combi Max and Vortex Combi models

6 - BOILER INSTALLATION

Connect a conventional flue

6.5

1 Lift off the rear part of the case top.

2 Remove the insulation from the rear top panel (do

not discard it) and remove the blanking panel.
Discard the panel, retaining the nuts and washers.

3 Unscrew the protective covers from the studs on the flue

dress panel, supplied in the literature pack. Place the
panel in position in the rear case top panel and secure in
place using the washers and nuts previously removed.
Note: The first section of Vortex Combi flue must
be in single wall rigid stainless steel flue pipe
suitable for condensing boilers.

4 Combi V3 and Combi Max - Fit the flue dress

plate to the hole in the rear section of the case top.

4a Vortex Combi - Cut the insulation into three equal

pieces and replace two - either side of the flue opening
in the case top panel.
Fit the conventional flue adaptor (Part No. CFCA15/
46 not supplied with boiler) on to the neoprene gasket
around the flue outlet on top of the boiler. Secure in
position using the 40 mm stainless steel bolt supplied
with the boiler as shown in Fig. 23.

Fig. 23 - Vortex Combi conventional flue adaptor

5 Position the flue pipe into socket.

Combi V3 and Combi Max - Make good the
connection using a suitable flexible high temperature
sealant (e.g. Silastic or similar) and rope seal.

6 Position the rear section of the previously prepared

case top over the first section of the flue.

7 Replace the rear section of the case top.

The expansion vessel fitted is supplied with a
charge pressure of 1.0 bar (equivalent to a max.
static head of 10.2 metres). The charge pressure
must not be less than the actual static head at the
point of connection. Do not pressurise the vessel
above 1.5 bar.

The air pressure in the vessel must be checked annually.

The central heating system volume, using the
expansion vessel as supplied, must not exceed the
recommended volumes. If the system volume is
greater, an extra expansion vessel (complying with BS

4841) must be fitted as close as possible to the central
heating return connection on the boiler. The charge
pressure of the extra vessel must be the same as the
vessel fitted in the boiler. Refer to BS 7074:1 for
further guidance.

The air charge pressure may be checked using a tyre
pressure gauge on the expansion vessel Schraeder
valve. The vessel may be re-pressurised using a
suitable pump. When checking the air pressure the
water in the heating system must be cold and the
system pressure reduced to zero.

Important: Ensure that the electrical supply has been
isolated before commencing.

If a Grant plug-in timer is used, a permanent 230 V
mains supply (fused at 5 Amp) must be taken to the
boiler. A three core cable is required to connect the
boiler terminal block to the live supply. Refer to
Section 12 for typical control system wiring diagrams.

1 Loosen (do not remove) the four screws

securing the control panel to the side panels,

hinge the panel forward and allow it to drop down
to gain access to the rear of the panel.

2 Remove the two screws securing the terminal block

cover and lift off the cover.

3 Remove the screws securing the cable clamp and

open the clamp.

4 Connect the power supply cable to the left hand

terminal block as follows:

Brown to mains Live - terminal 3

Blue to mains Neutral - terminal 2

Green/Yellow to mains Earth - terminal 1

Expansion vessel

6.6

Connect the power supply

6.7

Combi V3, Combi Max and Vortex Combi models

38

Connection of external remote timeswitch

6.8

Optional Grant internal timer

6.9

5 Connect a room thermostat as follows:

Remove the room thermostat link wire (6 and 7
on Combi V3 and Combi Max or 4 and 5 on
Vortex Combi) from the left hand terminal
block and connect the room thermostat to the
terminal block in accordance with the room
thermostat manufacturers instructions.

6 Connect a frost thermostat as follows:

Connect the frost thermostat to the left hand terminal
block using terminals 4 and 5 on the Combi V3 and
Combi Max or 6 and 7 on the Vortex Combi in
accordance with the thermostat manufacturers
instructions.

7 Replace the rear cover of the control panel.

8 Replace the terminal block cover and secure with

two screws previously removed.

See Section 12

Important: Any remote timer must be of a single
channel 230 V type with voltage free output contacts.

Important: Ensure electrical supply to boiler has
been isolated before fitting the timer.

1 Remove the screws securing the terminal block

cover and lift off the cover.

2 Pass a 4-core cable (or 4-core and earth if the timer to be

used has an earth connection) through the cable clamp in
the panel. Connect the two switch wires from the timer
to terminals 8 and 9. Connect the live, neutral (and earth
if required) from the timer to terminals 3, 2 & 1
respectively on the boiler terminal block.
See Section 12 for a typical wiring diagram.

3 Remove the link from terminals 8 and 9 on the

boiler terminal block.

4 Secure the cable in the cable clamp, replace the

wiring cover in position over the terminal block,
taking care not to trap any wires, and secure in
position with the screws previously removed.

5 Ensure that all external wiring is adequately supported.

6 Do not switch on the electricity supply at this stage.

6 - BOILER INSTALLATION

Important: Ensure electrical supply to boiler has
been isolated before fitting the timer.

1 From underneath the control panel, remove the screw

securing the bracket behind the timer aperture.

2 Remove the blanking piece from the timer aperture

in the control panel fascia by firmly pressing on the
Grant logo (in the centre of the black square) until
it is detached from the rear of the fascia. Remove
the blanking piece from the panel and the bracket
inside the aperture and discard both items.

3 Loosen (do not remove) the four screws

securing the control panel to the side panels,

hinge the panel forward and allow it to drop down
to gain access to the rear of the panel.

4 Remove the two screws securing the terminal block

cover and lift off the cover.

5 Remove the factory fitted link from terminals 8

and 9.

6 Remove the two top screws from the rear of the

control panel and loosen the two lower screws.
Remove the rear access cover.

7 Fit the 6-way plug on the timer wiring harness

firmly into the 6-way socket to connect the timer to
the boiler.

8 ET and MT kits - Carefully fit the timer into the

aperture.

9 MT kit only - From the rear of the control panel fit

the two fixing clamps, supplied, into the slots on
each side of the timer housing with the two 'legs'
towards the front of the timer. With the front of the
timer held against the fascia, push both clamps
towards the front of the timer as far as possible to
secure the timer firmly in position.

10 Replace the rear cover of the control panel.

11 Replace the terminal block cover and secure with

the two screws previously removed.

12 Do not switch on the electricity supply at this stage.

Refer to the User Instructions provided for
operating and setting the timer.

39

Combi V3, Combi Max and Vortex Combi models

6 - BOILER INSTALLATION

See Fig. 9

If a two pipe system is to be used refer to Section 5.3.6.

1 Remove the oil inlet plug from the fuel pump and

connect the elbow of the flexible fuel line supplied
with the boiler.

2 Connect the flexible fuel line to the rigid supply using

the adaptor supplied. The supply enters through one
of the holes at the bottom of the case sides.

Connect the fuel supply

6.10

Fig. 24 - RDB burner components

1 Pump
2 Control box
3 Reset button with lock-out lamp
4 Flange with gasket (do not remove from boiler)

7

8

1

2

3

5

4

6

5 Air damper adjustment screw
6 Air supply tube connection (balanced flue)
7 Pump pressure adjustment screw
8 Pressure gauge connection

Combi V3, Combi Max and Vortex Combi models

40

1 Automatic air vent(s) are fitted to the top of the

boiler. Check that the small cap on the top of each
air vent is screwed on fully, then unscrew it one
complete turn - the cap remains in this position
from now on.

2 If the flexible filling loop is used to fill the system, ensure

it is connected and that the valve connecting it to the
boiler is open and the valve at the front is closed.
A valve is open when the operating lever is in line with
the valve, and closed when it is at right angles to it.

3 Ensure that the mains cold water supply valve is open

(operating lever in line with the valve), then turn on the
mains cold water supply and gradually open the front
valve on the filling loop until water is heard to flow.

4 Vent each radiator in turn, starting with the lowest

one in the system, to remove air.

5 It is important the circulating pumps are properly

vented to avoid them running dry and the bearings
being damaged.

To gain access to the pump in the Combi V3 and
Combi Max, and the Heating pump in the Vortex
Combi, it is necessary to lower the control panel.

Loosen (but do not remove) the four fixing screws
securing the control panel to the side panels, hinge
the panel forward to gain access to the pump.

Unscrew and remove the plug from the centre of
the pump. Using a suitable screwdriver rotate the
exposed spindle about one turn. When water starts
to trickle out, replace the plug.

On the Vortex Combi the Hot water pump must
also be vented as described above.

6 Check the operation of the safety valve by turning

the head anticlockwise until it clicks. The click is
the safety valve head lifting off its seat allowing
water to escape from the system.
Check that this is actually happening.

7 - FILL AND VENT THE SYSTEM

Fill the system

7.1

Completion

7.2

7 Continue to fill the system until the pressure gauge

indicates between 0.5 and 1.0 bar. Close the fill
point valve and check the system for water
soundness, rectifying where necessary. Water may
be released from the system by manually operating
the safety valve until the system design pressure is
obtained.

8 The system design pressure (cold) should be

between 0.5 bar and 1.0 bar. The pressure is
equivalent to the maximum static head in bar + 0.3
(1 bar = 10.2 metres of water), where the static
head is the vertical height from the centre of the
expansion vessel to the highest point of the system.

9 Close the valves either side of the filling loop and

disconnect the loop.

Please ensure that the OFTEC CD/10 installation
completion report (provided with the boiler) is
completed in full.

Leave the top copy with the User. Retain the two
carbon copies.

Ensure that the User Information pack (supplied with
the boiler) is handed over to the Householder.

41

Combi V3, Combi Max and Vortex Combi models

8 - COMMISSIONING

Refer to Fig. 25 or 25a for boiler controls

Fig. 25a Boiler controls (Vortex Combi 36 shown)

Fig. 25 - Combi V3 and Combi Max boiler Controls

It is important that the following commissioning
procedure is carried out to ensure safe and efficient
operation of the boiler.

Note: Check that the baffles are in position and
that the cleaning cover is correctly fitted and a
good seal made.

1 Check that the water system has been vented and

pressurised, and there are no leaks.

2 Check that all fuel line valves are open.

3 Remove the plastic burner cover (two screws) if it

was not previously removed.

Combi V3, Combi Max and Vortex Combi models

42

4 Connect a combined vent manifold and pressure

gauge to the pressure gauge connection port on the oil
pump. See Fig. 24. Open the vent screw on your vent
manifold to vent the supply while the pump is running.

5 Set the Heating switch to 'Hot Water Only' (Combi

V3 and Combi Max) or to 'OFF' (Vortex Combi).
Check that all system controls are calling for heat and
turn the boiler thermostat to maximum. Switch on the
electricity supply to the boiler.

6 Set the boiler On/Off switch to 'ON' and the Store

switch to 'ON' (Vortex Combi). Fully open a hot tap
and allow it to run for a few moments to vent the
internal primary circuit. The boiler pump in the Combi
V3 and Combi Max or the Hot Water pump in the
Vortex Combi will operate and the burner should
light within about 12 seconds. If the burner does not
light and the 'Lock-out' reset button lights, wait for
about 45 seconds then press the reset button to restart
the ignition process. This procedure may have to be
repeated during first lighting.
Close the hot tap. The burner will continue to fire to
heat the primary water in the boiler or primary store
(Vortex Combi) until the required temperature is
reached.
Note: On the Vortex Combi the Hot Water pump will
continue to run for a short period after the burner has
stopped.

7 Set the Heating switch to 'CONSTANT' . The boiler

will now be operating in the central heating mode.
Note: The burner may not fire immediately.

8 With the burner alight, check the fuel pressure. Refer

to the Technical Information, Section 4.3, 4.4 or 4.6.
Adjust the pressure if necessary - see Fig. 24.

9 Operate the boiler until it reaches normal operating

temperature. Check oil supply/return pipe for leaks,
rectifying where necessary.

10 Switch the boiler off, remove the pressure gauge and

replace the plug in the pump.

11 Having ensured that there are no oil leaks, replace the

burner cover. Tighten the two fixing screws. Ensure
the flexible air tube is connected to the burner.

12 A flue gas sampling test point is provided. This is

located in the cleaning door on the front of the
Combi 90 V3, Combi Max and Vortex Combi, and
on the top of the Combi 70 V3.

13 After allowing the burner to run for 20 minutes -

Check the smoke number, if satisfactory check the
CO2 level. Set the CO2 to the value given in Section

4.3, 4.4 or 4.6. for the boiler and fuel used. Adjust
the burner air regulator, see Fig. 24, turning the
screw anti-clockwise closes the damper and
increases CO2 level, turning the screw clockwise
opens the damper and reduces CO2 level.
Re-check the smoke number if the air damper has
been moved.
Under no circumstances must the smoke number be
above 1.

Note: It is important that the air damper is
correctly set.

14 Check the flue gas temperature.

15 When the boiler has been adjusted and is running

satisfactorily, balance the central heating system by
adjusting the radiator lock shield valves. Start with
the radiator nearest the boiler and adjust the valves
to achieve the required temperature drop across
each radiator.
If thermostatic radiator valves have been installed,
check the system by-pass.

16 Switch off the boiler.

17 With the system hot, check again for leaks, rectifying

where necessary. Drain the heating system while it is
hot to complete the flushing process.

18 Refill, vent and pressurise the system as described

in Section 7.2, adding a suitable inhibitor. For
further information concerning inhibitors contact
Grant Engineering (UK) Limited.

19 Replace the case bracing bracket and top panel, if

not already fitted.

Note: After commissioning the boiler, complete the
Commissioning Report on page 2 of these
instructions and the OFTEC CD/11 commissioning
report. Leave the top copy with the User and
return the two carbon copies.

If the boiler is to be left in service with the User, set
the controls, timer (see Section 1) and room thermostat
(if fitted) to the User's requirements then refer to
Section 9.

If the boiler is not to be handed over immediately,
close the boiler fuel supply valve and switch off the
electricity supply.
If there is any possibility of the boiler being left during
frost conditions, then the boiler and system should be
drained.

8 - COMMISSIONING

43

Combi V3, Combi Max and Vortex Combi models

9 - INFORMATION FOR THE USER

10 - BOILER SERVICING

Important notes prior to servicing

10.1

The User must be advised (and demonstrated if
necessary) of the following important points:-

1 How to light and turn off the boiler and how to

operate the system controls.

2 The precautions necessary to prevent damage to

the central heating system and to the building, in
the event of the boiler not being in operation
during frost conditions.

3 The importance of servicing the boiler to ensure

safe and efficient operation. This should normally
only be required once a year.

4 The type of fuel used.

5 That any servicing or replacement of parts must

only be carried out by a suitably qualified engineer.

6 Ensure that the boiler controls and room thermostat

(if fitted) are set to the User's requirements.

7 Tell the User the system pressure and show them

the position of the safety valve discharge pipe.

8 Show the User how to reset the overheat thermostat

and how to restart the boiler if it goes to 'Lock-out'.

Leave this Instruction manual with the User.

Ensure the User information pack has been given
to the Householder.

To ensure efficient operation of the boiler it is
recommended that it is checked and serviced as
necessary at regular intervals. The frequency of
servicing will depend upon the particular installation
conditions and usage, but in general once per year
should be adequate.

Servicing and replacement of parts must only be
carried out by a suitably qualified engineer.

Important: Details of every service should be recorded
in the Service Log in the Boiler Handbook. This
information may be required to validate the Grant
extended warranty.

IMPORTANT

Before starting any work on the boiler, or fuel supply
please read the health and safety information given in
Section 15 on page 61.

1 Check the flue terminal and ensure it is not blocked

or damaged.

2 Run the boiler and check the operation of its

controls.

3 Ensure that all water/fuel system connections and

fittings are sound. Remake any joints and check the
tightness of any fittings that may be leaking.
Check the expansion vessel air charge. See Section 6.6.
Check the system pressure. Refill, vent and re­pressurise the system as necessary. See Section 7.1.

4 Check that any ventilation openings are adequate

and are clear. See Section 5.6.

5 Remove any sludge/water from the fuel tank by

opening the sludge valve at the lower end of the
tank.

6 With the fuel supply valve closed, clean/replace the

filter element and clean the filter bowl.

7 Flexible fuel supply pipes should be inspected

annually when the boiler is serviced and replaced
every two years. If in doubt replace the pipes.

Warning: Before servicing, set the boiler On/Off
switch to 'OFF', isolate the electricity supply and close
the fuel supply valve. Allow the boiler to cool.

The data label on the inside of the case side panel will
indicate the fuel used and nozzle fitted.

Combi V3, Combi Max and Vortex Combi models

44

10 - BOILER SERVICING

Dismantling prior to servicing

10.2

Cleaning the boiler

10.3

Fig. 26 - Combi 70 V3 baffle positions

Fig. 27 - Combi 90 V3 baffle positions

1 Pull off the front panel.

2 Carefully lift up the expansion vessel and remove it

from the front of the boiler. Place it on the floor,
taking care not to strain the flexible pipe.

3 Disconnect the flexible air tube from the burner.

4 Remove the burner fixing nut (top of mounting

flange) and withdraw the burner. If required,
disconnect the flexible oil line(s), use a suitable
container to prevent any oil spillage.

Note: If two flexible lines are connected to the
burner, identify (mark if necessary) which is the
inlet and return if they are to be disconnected.

4 Check the condition of the flue, clean as necessary.

5 Check the condition of the front cleaning door seal on

the Combi 90 V3, Combi Max and Vortex Combi, or
the cleaning cover gasket on the Combi 70 V3,
Replace if necessary.

6 Replace the baffles, ensuring they are correctly

fitted. See Fig. 26, 27, 28, 29 or 30.

See Fig. 26, 27, 28, 29 or 30

1 Combi 90 V3, Combi Max and Vortex Combi

Remove the four nuts and washers securing the
front cleaning door and withdraw the door.
Take care - it is heavy.

1 Combi 70 V3

Remove the two nuts and washers securing the top
cleaning cover and lift it off the boiler.

2 Remove the baffles as shown in Fig. 26, 27, 28, 29

or 30.

3 Remove all deposits from the baffle plates and all

the boiler internal surfaces using a stiff brush and
scraper if necessary.

45

Combi V3, Combi Max and Vortex Combi models

10 - BOILER SERVICING

Fig. 28 - Combi Max baffle positions

Fig. 29 - Vortex Combi 26

Fig. 30 - Vortex Combi 36

7 Vortex Combi - Pull out the spiral turbulators from

the heat exchanger tubes. See Fig. 31.
Clean the turbulators using a stiff brush

Test the heat exchanger condensate drain by pouring
water into one of the lower tubes and observe whether
the water discharges from the 22 mm condensate
outlet. Replace the turbulators.

8 All boilers - Replace the cleaning door or cover,

securing it in position with the nuts and washers
previously removed.

9 Vortex Combi - Remove the condensate trap and

check that it is not blocked and is operating
correctly, i.e. the float is free to move. Clean the
trap and float as required.

Check that the boiler condensate outlet is
unobstructed. Clean if necessary.

IMPORTANT: The condensate trap and
condensate outlet must be checked on every service
and cleaned as necessary.

Combi V3, Combi Max and Vortex Combi models

46

Fig. 32

IMPORTANT: The electrode settings given above
MUST be observed

4 ± 0.3 mm

Clamp screw

2 to 2.5 mm (Combi 70 V3)

3 to 3.5 mm (Combi 90 V3, Combi Max

and Vortex Combi)

Cleaning the burner

10.4

10 - BOILER SERVICING

Fig. 31 Vortex Combi turbulators

See Section 14.1

1 Combustion head - Loosen the two screws securing

the combustion head to the burner flange and withdraw
the head. Clean and refit the combustion head.

2 Inspect the ignition electrodes - With the combustion

head removed, loosen the electrode clamp screw and
withdraw the electrode assembly. Wipe clean and
check for any cracks in the ceramic insulation. Replace
if necessary.
Check the electrode settings - Electrode tips
approximately 4 mm apart and 2 to 2.5 mm
(Combi 70 V3) or 3 to 3.5 mm (Combi 90 V3,
Combi Max, Vortex Combi) in front of the
nozzle, see Fig 32.

3 Nozzle - The nozzle should be replaced on an

annual service.
Check that the nozzle fitted is the correct size and
type , refer to tables in Section 4.3, 4.4 or 4.6 and
boiler data label.

Do NOT attempt to clean the nozzle.

Remove and replace the nozzle using a good fitting
spanner (16 mm). The use of an ill-fitting spanner will
damage the nozzle and could lead to an incorrect
flame pattern. Always check the electrode settings
after replacing the nozzle, see Fig. 32.

4 Photocell - The photocell is a push-fit in the burner

body. Carefully pull out the photocell to clean.

5 Fan - With the air intake spigot removed, remove the

screws securing the fan housing cover (R/H side of
burner) and remove the cover. Inspect the fan and
housing and clean as necessary. Replace the cover.

6 Pump filter - With the burner cover removed,

remove the four screws securing the pump end
cover. Remove the filter and wash in kerosene.
Replace the filter and end cover, ensure the 'O' ring
is in position.

To ensure safe and efficient operation of the boiler it
is important that re-commissioning is carried out,
especially combustion checks (CO2 level, flue gas
temperature and smoke number) after the boiler has
been serviced.

Refer to the Commissioning instructions starting on
page 41.

47

Combi V3, Combi Max and Vortex Combi models

Main Components

A Cold water inlet isolating valve
C Lower pump union
D Upper pump union - isolating valve
E Heating check valve
F Filling hose
G Filling loop - cold inlet isolating valve
I Thermostatic mixing valve
J Circulating pump
K Microswitch assembly
L Diverter valve
M Plate heat exchanger
P Flow restrictor
Q Heating flow isolating valve
R Heating return isolating valve
S Pressure switch

Connections

1 Diverter valve - cold water inlet
2 Diverter valve - primary inlet
3 Diverter valve - primary outlet
4 Plate heat exchanger - hot water outlet
5 Cold water Inlet isolating valve - outlet
6 Plate heat exchanger - primary outlet
7 Plate heat exchanger - cold water inlet
8 Plate heat exchanger - primary inlet
9 Mixing valve - cold water inlet
10 Primary return isolating valve - inlet
11 Mixing valve - hot water inlet
12 Mixing valve - blended water outlet
13 Primary flow from boiler

Fig. 33 - Combi V3 and Combi Max components/connections

11 - BOILER COMPONENTS

Combi V3, Combi Max and Vortex Combi models

48

11 - BOILER COMPONENTS

Fig. 33a - Vortex Combi components/connections

Main Components

1 Circulating pump - heating
2 Circulating pump - hot water (primary store)
3 Plate heat exchanger
4 Pressure switch
5 Flow switch
6 Thermostatic mixing valve
7 Automatic air vent
8 Manual air vent (x 2)

9 Pressure relief valve
10 Filling hose
11 Filling loop - cold inler isolating valve
12 Filling loop - heating system isolating valve
13 Isolating valve - cold inlet
14 Isolating valve - heating return
15 Non return valve (x 2)

Connections/pipe

A Heating system flow - push-fit elbow
B Heating system return - push-fit elbow
C Cold water inlet - push-fit elbow
D Hot water outlet - push-fit elbow
E Pump isolating valves - heating pump
F Pump isolating valves - hot water (store) pump
G Primary inlet to store
H Primary outlet from store
I Primary inlet to condensing heat exchanger
J Primary outlet from condensing heat exchanger
K Primary return to main heat exchanger
L Primary flow manifold
M Primary return manifold
N Primary flow to heating (store) pump
O Primary flow to plate heat exchanger
P Primary return to boiler
Q Cold water inlet manifold
R Hot water flow to blending valve
S Hot water outlet from blending valve

49

Combi V3, Combi Max and Vortex Combi models

Functional flow wiring diagram - Combi V3 and Combi Max

12.2

1 2 3 4 5 6

M

RD

RD

RD

BL

Boiler

terminal

block 2

R/S link (red)

L

8

7

6

5

9

N

E

10

12

13

14

15

16

17

'Plug in' timer socket

1A

3A

2A

Heating

switch

Boiler
on/off

switch

c/w neon

C

2

G/Y

No

C

C

No

E N L

Pump

E

L

N

Burner

Pressure
switch

Live

Neutral

Burner live

Flow switch

N

E

L

4B

5B

1A

2A

Boiler terminal
block 2

G/Y

G/Y

G/Y

G/Y

BL

BL

BL

BL

BL

BL

BL

RD

RD

RD

RD

BL

RD

RD

RD

RD

RD

RD

RD

RD

OR

RD

Y

Y

BR

BR

BR

Electonic

PCB board

BLK

Y

OR

1
2
3
4

Chassis earth
to bolt in boiler
casing

Chassis earth
to bolt in boiler
casing

Pressure switch

neon (amber)

Overheat stat

neon (red)

Limit

stat

G/Y

RD

BL

Pump

flow

switch

Burner

flow

switch

1

23456

Mains supply
(use 2 pole isolator
with power 'on'
indicator)

Frost
thermostat
(if fitted)

Note: Remove link
8 to 9 (yellow) if
timer is fitted

Note: If room thermostat is
fitted, remove link 6 to 7 (red)
and connect room thermostat
in its place

'Plug in' timer
24 hr mechanical
or 7 day timer

11

G/Y

OR

Y

Colour code: BLK Black, BL Blue, BR Brown, RD Red, Y Yellow G/Y Green/Yellow, OR Orange

12 - WIRING DIAGRAMS

Control panel wiring diagram - Combi V3 and Combi Max

12.1

Combi V3, Combi Max and Vortex Combi models

50

4B

1A

5B

2A

OFF

3A

TIMED

CONSTANT

1A

2A

1

L

Burner live

Neutral

Live

Flow switch

11

A1

A2

6

7

10

9

Relay No.1

(bottom)

2

C

6

10

Relay No.2 (top)

9

17

20
21
22

19

18

L N E L N E

14

16

15

E

L

N

4B

5B

NC

NO

2

345

6

7

8

10

11

12

13

9

N

E

BL

RD

RD

RD

BLK

BR

BR

BLK

BL RD

OR

OR

BR

RD

OR OR

RD BLK BLK

BL

BLK

G/Y

BL

BL

G/Y

G/Y

BR

OR

OR

OR

OR

OR

OR

BL

BL

BL

BLK

BLK

RD

BR

G/Y

G/Y

6

54

1

2

3

Plug-in timer

socket

Heating

switch

Pressure

switch

Flow

switch

Boiler

terminal block

Mains supply

use 2 pole islolator

with power 'on' indicator

Remove link 8 to 9

(yellow) if timer is fitted

Frost thermostat

if fitted

If room thermostat is fitted

remove link 4 to 5 and connect

room thermostat in its place

Chassis earth

to bolt in panel

Chassis earth

to bolt in boiler

casing

Heating

pump

DHW
pump

Burner

Hot water

store

Pressure

switch neon

(amber)

Burner live

Neutral

Live

Flow switch

CH (adjustable)

PCB board

DHW (fixed)

PCB board
on bracket

Limit thermostat

Overheat thermostat

neon (red)

Boiler On/Off

switch with neon

OR

BL

Y

L

N

E

G/Y

A1

A2

OR

BLK

12 - WIRING DIAGRAMS

Control panel wiring diagram - Vortex Combi

12.3

Functional flow wiring diagram - Vortex Combi

12.4

Colour code:

BLK Black
BL Blue
BR Brown
RD Red
Y Yellow
G/Y Green/Yellow
OR Orange

51

Combi V3, Combi Max and Vortex Combi models

12 - WIRING DIAGRAMS

Typical connection of external timer

12.5

Important: If a remote timer is used, it must be a single channel

230V unit incorporating voltage free output contacts.

Connection of Grant remote wall mounted mini programmer

12.6

Grant programmable room thermostat

12.7

A programmable room thermostat - Part No. RSKIT is available from Grant UK. The thermostat has a 5/2 day
operation and enables six time and temperature changes each day. The thermostat incorporates frost protection and an
On/Off facility.

Combi V3, Combi Max and Vortex Combi models

52

13 - FAULT FINDING

Combi V3, Combi Max and Vortex Combi - Boiler faults on central heating and hot water

13.1

Boiler will not start

Low pressure cut-out activated (amber neon on panel lit).

No electrical supply to burner.

No electrical supply to boiler.

Check controls are switched on and calling for heat.

Overheat thermostat has operated (red neon on panel lit).

Boiler thermostat and/or overheat thermostat faulty.

Fault with burner.

No fuel supply

Oil tank empty.

Isolating valve(s) in fuel supply line closed.

Fire valve closed.

Fuel line filter is blocked.

Oil supply line is air locked.

Excessive combustion air.

Fault with burner.

Insufficient combustion air supply to burner.

Incorrect or faulty nozzle fitted.

Fuel pressure too high.

Insufficient combustion air supply to burner.

Contaminated combustion air (balanced flue).

Insufficient oil flow to burner due to restriction in supply line.

Excessive combustion air.

Refill system to 0.5 - 1.0 bar.

Check for 230 V at boiler terminal block.

Check boiler On/Off switch is set to 'ON'.

Set boiler thermostat to maximum.

Set 3-position Heating switch to 'Constant'.

Check and reset thermostat as necessary.

Check for 230 V output from BURNER LIVE terminal of PCB.

Check continuity of overheat thermostat - replace as necessary.

Press reset button - no more than twice.

If burner does not operate refer to burner fault finding chart.

Check tank and refill as necessary.

Check and open valves as necessary.

Check and reset as necessary.

Check and clean as necessary.

Vent oil supply line at pump.

Reset burner air damper and check combustion.

Refer to burner fault finding chart.

Check flue terminal is clear (balanced flue).

Check room ventilation is adequate (conventional flue).

Check condition of burner fan.

Check air damper setting on burner.

Check nozzle size and type and replace if necessary.

Check fuel pressure and adjust as necessary.

Check as for high smoke number (above).

Check the flue terminal is unobstructed

Connect vacuum gauge to pump and check pump vacuum.

Check for blockage in filter, fire valve, valves or pipe and rectify.

Reset burner air damper and check combustion.

FAULT

POSSIBLE CAUSE

ACTION

Burner lights but goes to lock-out

Burner not lighting

Oil & electricity present at burner

Burner fires but smoke visible

from flue or high smoke number

Burner pulsates

Burner cycles On and Off

53

Combi V3, Combi Max and Vortex Combi models

13 - FAULT FINDING

Combi V3, Combi Max and Vortex Combi - Boiler faults on central heating and hot water - continued

13.2

Flue is blocked.

Insufficient flue draught.

Flue pipe or liner is too large or existing stack is unlined.

Insufficient combustion air supply to burner.

Insufficient combustion air supply to burner.

Incorrect or faulty nozzle fitted.

Fuel pressure too low.

Oil leak in supply line or burner.

Leak around boiler cleaning door.

Burner not correctly fitted on mounting flange.

Burner seal 'O' ring damaged or missing.

Leakage around flue connection.

Faulty boiler thermostat.

Thermostat sensor not connected to PCB (Vortex Combi only).

Faulty overheat thermostat.

Check flue is clean and unobstructed - rectify as necessary.

Check flue draught and improve flue as necessary.

Check flue condition/size and alter as necessary.

Check as for high smoke number (above).

Check that an extract fan is not pulling combustion gases from burner.

Check as for high smoke number (above).

Check nozzle size and type and replace if necessary.

Check fuel pressure and adjust as necessary.

Check all joints and flexible hose for leaks and rectify as necessary.

Check gasket, re-tighten nuts or replace gasket as necessary.

Remove and re-fit burner ensuring correct fitting.

Check and replace 'O' ring as necessary.

Check and re-seal flue as necessary.

Check and replace as necessary.

Check and rectify as necessary.

Check and replace as necessary.

FAULT

POSSIBLE CAUSE

ACTION

Fumes and puffing on starting

(Conventional flue)

Overheat thermostat operating

Combustion fume smells

Oil smells

Flame slow to stabilise on starting

Combi V3, Combi Max and Vortex Combi models

54

13 - FAULT FINDING

No water flowing from hot tap

Mains water supply is not connected to cold water inlet of boiler.

One or more isolating valves, stop cocks, etc. in the pipework are closed.

The cold water isolating valve in the boiler is closed.

There is a blockage (or blockages) in the pipework.

Hot tap is not connected to hot water outlet of boiler.

Insufficient flow of water through boiler.

Boiler cold water and hot water connections reversed.

Thermostatic mixing valve incorrectly fitted.

Pump is not operating in hot water mode.

Diverter valve microswitch(es) faulty.

Diverter valve microswitches not operated.

Diverter valve seized.

Diverter valve diaphragm failed.

Flow of water through boiler too high.

Boiler thermostat incorrectly set

Thermostatic mixing valve incorrectly set.

Faulty boiler thermostat.

Pump speed setting too low.

Pump is incorrectly fitted.

Burner not firing for hot water (after a short time).

Burner oil pressure set too low at oil pump.

Incorrect oil nozzle fitted to burner.

Check and rectify as necessary.

Open all valves in pipework to and from boiler.

Open valve (situated above pump in front of boiler).

Check and rectify as necessary.

Check and rectify as necessary.

Check flow is at least 3 litres/min - rectify as necessary.

Check and rectify as necessary.

Check hot and cold inlets are connected correctly.

Check operation of diverter valve.

Check pump is free to rotate and is vented.

Check for 230V supply to pump.

Check electrical continuity of pump microswitch.

Check wiring continuity from pump to microswitch.

Check switch continuity, replace if faulty.

Check diverter valve diaphragm.

Remove, dismantle and clean.

Replace diaphragm or complete diverter valve.

Reduce flow and check water temperature.

Set boiler thermostat to maximum.

Set mixing valve to setting '4.5'.

Check continuity and replace if necessary.

Set pump speed switch to maximum (top position).

Check and rectify as necessary.

Check operation of burner on central heating.

If burner faulty, refer to burner fault finding chart.

Check electrical continuity of burner microswitch.

Check electrical continuity of thermostat.

Check operation of diverter valve.

Check wiring continuity from burner to microswitch.

Check and set oil pressure to correct value (see Section 4.3, 4.4, 4.6).

Check and fit correct nozzle (see Section 4.3, 4.4, 4.6).

No hot water operation

FAULT

POSSIBLE CAUSE

ACTION

Hot water for short period only

Low water temperature at tap

Combi V3 and Combi Max only - Central heating OK - poor or no domestic hot water

13.3

55

Combi V3, Combi Max and Vortex Combi models

13 - FAULT FINDING

No operation on heating

Timeswitch either not set, or not in an 'ON' period.

Timeswitch not operating.

Faulty timeswitch.

Faulty timeswitch switch contacts.

Timeswitch OK but not switching boiler on.

Heating switch set to 'HOT WATER ONLY'.

Room thermostat not calling for heat.

Faulty room thermostat.

No room thermostat or external timeswitch connected to boiler.

Boiler thermostat is set too low.

Boiler thermostat faulty.

Boiler is underfired.

Combustion setting of burner incorrect.

Boiler heat exchanger is sooted up.

Check setting and set to 'Constant' to test.

Check power supply to timeswitch.

Check and replace if necessary.

Check continuity of switch, replace if necessary.

Check continuity of wiring to timeswitch.

Check and set switch to 'Constant' to test.

Set thermostat to call and check boiler operates.

Check continuity of thermostat, replace if necessary.

Check link fitted between 8 & 9 on boiler terminal block.

Check and reset as necessary.

Check and replace if necessary.

Check nozzle size & fuel pressure, correct as necessary.

Check settings and correct as necessary.

Check boiler & baffles and clean as necessary.

FAULT

POSSIBLE CAUSE

ACTION

Flow temperature low

Combi V3 and Combi Max only - Domestic hot water OK - poor or no central heating

13.4

Combi V3, Combi Max and Vortex Combi models

56

13 - FAULT FINDING

Vortex Combi only - Central heating OK - poor or no domestic hot water

13.5

No water flowing from hot tap

No hot water operation

FAULT

Hot water for short period only

Low water temperature at tap

Mains water supply is not connected to cold water inlet of boiler.

One or more isolating valves, stop cocks, etc. in the pipework are closed.

The cold water isolating valve in the boiler is closed.

There is a blockage (or blockages) in the pipework.

Store switch is set to OFF.

Insufficient flow of water through boiler.

Hot tap is not connected to hot water outlet of boiler.

Boiler cold water and hot water connections reversed.

Flow switch is not operating.

Primary store is not up to temperature.

Primary store (hot water) pump is not operating.

Faulty Hot Water PCB sensor.

Faulty Hot Water PCB.

Relay No.1 faulty - not switching.

Flow of water through boiler too high.

Thermostatic mixing valve incorrectly set.

Primary store (hot water) pump speed too low.

Faulty Hot Water PCB sensor.

Faulty Hot Water PCB.

Burner not firing for hot water (after a short time).

Note: Burner will not necessarily fire as soon as tap is opened.

Burner oil pressure set too low on oil pump.

Incorrect nozzle fitted to burner.

POSSIBLE CAUSE

Check and rectify as necessary.

Open all valves in pipework to and from boiler.

Open valve fully (located in the top right of boiler).

Check and rectify as necessary.

Check store switch is set to ON (on boiler control panel).

Check flow is at least 3 litres/min - rectify as necessary.

Check and rectify as necessary.

Check and rectify as necessary.

Check flow switch is correctly fitted - in line with flow.

Check continuity across flow switch between terminals 10 and 11.

Set store switch to ON - burner and hot water pump should start.

Check for 230 V supply to pump with water on.

Replace sensor and check operation.

Check for 230 V output from 'Burner' terminal on PCB.

If no output - replace Hot Water PCB and check operation.

Check for 230 V to 'Flow switch' terminal of Heating PCB.

Reduce flow and check water temperature.

Set mixing valve to setting '4.5'.

Check pump speed is set to maximum - setting 3.

Replace sensor and check operation.

Check for 230 V output from 'Burner' terminal on PCB.

If no output - replace Hot Water PCB and check operation.

Check operation of boiler on heating - set switch to 'Constant'.

If burner faulty, refer to burner fault finding chart.

Check and set oil pressure to correct value (see Section 4.3, 4.4, 4.6).

Check and fit correct nozzle (see Section 4.3, 4.4, 4.6).

ACTION

57

Combi V3, Combi Max and Vortex Combi models

13 - FAULT FINDING

Vortex Combi only - Domestic hot water OK - poor or no central heating

13.6

No operation of boiler on

heating

Boiler switch is set to OFF.

Heating switch is set to OFF.

Room thermostat (if fitted) not calling for heat.

Timeswitch either not set or not in an ON period.

Timeswitch not operating.

Faulty timeswitch.

Faulty timeswitch contacts.

Faulty room thermostat.

No room thermostat or external timeswitch fitted.

Faulty Heating PCB sensor.

Faulty Heating PCB.

Faulty relay No. 2.

Boiler temperature control set too low.

Heating pump speed too low.

Heating pump not operating.

Primary store sensor not operating correctly.

Faulty relay No. 1.

Check boiler On/Off switch is set to ON (on boiler control panel).

Check heating switch is set to TIMED.

Set thermostat to call for heat and check boiler operates.

Check setting and set to CONSTANT to check boiler operates.

Check power supply to timeswitch.

Check and replace as necessary.

Check continuity of switch and replace as necessary.

Check continuity of thermostat and replace if necessary.

Check links are fitted between terminals 4 & 5 and 8 & 9.

Replace sensor and check operation.

Check for 230 V output from BURNER LIVE terminal.

If no 230 V output - replace PCB.

Check for 230 V supply to burner - between terminals 20 & 21.

Check for 230 V supply to heating pump - between terminals 14 & 15.

Check and set as necessary.

Check pump speed and set as required.

Check for 230 V supply to pump.

Check sensor is correctly located in pocket on front of store.

Check sensor lead is correctly connected to Hot Water PCB.

Check for 230 V supply to Hot water pump.

FAULT

POSSIBLE CAUSE

ACTION

Flow temperature low

Little or no heating flow

ATTENTION

If either sensor is disconnected from it's respective PCB, then that PCB will operate as if a demand was present and supply 230

V from the BURNER

LIVE terminal producing the following conditions:

Heating PCB sensor disconnected - Burner and heating pump will run continuously until the limit thermostat operates to shut down the boiler.

Store (hot water) PCB sensor disconnected - Burner and store pump will run until Heating PCB stops burner (via sensor on flow pipe). Store pump

continues to run. Note: - The boiler cannot provide flow to heating system in this condition - but will continue to provide hot water (and re-heat the

primary store) as required.

Combi V3, Combi Max and Vortex Combi models

58

13 - FAULT FINDING

Riello RDB burner fault finding

13.7

59

Combi V3, Combi Max and Vortex Combi models

Riello RDB burner - exploded view

14.1

1 Not applicable - ­2 Flange 3005786 RBS28
3 Combustion head LD2SX (70V3) 3008859 RBS132
3 Combustion head LD3 (90V3) 3008768 RBS127
3 Combustion head T2 (Vortex 26) 3002423 RBS147
3 Combustion head T3 (Vortex 36) 3002447 RBS144
3 Combustion head T5 (Max) 3002533 RBS150
4 Electrode assembly (70V3 only) 3008860 RBS133
4 Electrode assembly 3007513 RBS108
5 Screw (70V3 only) 3008875 RBS137
5 Electrode bracket 3006552 RBS29
6 Nozzle holder (70V3 only) 3008861 RBS134
6 Nozzle holder 3008642 RBS111
7 Collar 3008643 RBS112
8 High voltage lead 3008794 RBS129
9 Air damper assembly 3008647 RBS116
10 Fan (70V3, 90V3 and Vortex 26) 3005708 RBS39
10 Fan (Vortex 36) 3008645 RBS142
10 Fan (Max) 3005788 RBS151
11 Photocell 3008646 RBS115

Key

No.

Description Riello

Part No.

Grant

Part No.

Key

No.

Description Riello

Part No.

Grant

Part No.

12 Capacitor 4.5 µF 3002837 RBS149
13 Seal kit 3008878 RBS140
14 Needle valve 3007582 RBS109
15 Regulator 3008651 RBS120
16 Pump seal 3000439 RBS14
17 Pump 3008654 RBS101
18 'O' ring 3007162 RBS08
19 Filter - 'O' ring 3008653 RBS122
20 Connector 3003602 RBS35
21 Flexible pipe 3007672 RBS36
22 Tube 3008644 RBS113
23 Pressure gauge connector 3008876 RBS138
24 Drive coupling 3000443 RBS16
25 Solenoid 3008648 RBS117
26 Motor 3002836 RBS102
27 Cover 3008649 RBS118
28 Control box assembly 3008652 RBS103
29 Solenoid lead 3008851 RBS139
30 Cover 3008879 RBS141
31 Air tube spigot 3062774 RBS143

Combi

70 V3

14 - BURNER SPARE PARTS

Combi V3, Combi Max and Vortex Combi models

60

14 - BURNER SPARE PARTS

Burner Heads

61

Combi V3, Combi Max and Vortex Combi models

15 - HEALTH AND SAFETY INFORMATION

Under the Consumer Protection Act 1987 and Section 6 of the Health & Safety at Work Act 1974, we are required to
provide information on substances hazardous to health (COSHH Regulations 1988).
Adhesives, sealants and paints used in the manufacture of the product are cured and present no known hazards when
used in the manner for which they are intended.
The following other materials are present in the product:

Insulation materials

Material Types: Ceramic fibre board, mineral wool.

Description: Rigid board, slabs, sleeves, gaskets, ropes.

Known Hazards: May cause temporary irritation or rash to skin. High dust levels may irritate eyes and upper

respiratory system.

Precautions: Avoid unnecessary or rough handling, or harsh abrasion of boards. Normal handling and use of

material should not produce high dust levels.
Avoid inhalation, and contact with skin and eyes.
After handling always follow normal good hygiene practices.

Protection: Use disposable gloves, face mask and eye protection.

First Aid: Eyes - If irritation occurs, wash eyes with copious amounts of water. If symptoms persist, seek

immediate medical advice.
Skin - If irritation occurs, wash under running water before washing with soap and water.
Inhalation - Remove to fresh air, drink water to clear throat and blow nose to remove dust/fibres.
Ingestion - Drink plenty of water.

Sealants

Material Types: Silicone elastomer.

Description: Sealant and adhesive.

Known Hazards: Irritation to eyes.

Precautions: Avoid inhalation of vapour, contact with eyes and prolonged or repeated contact with skin.

After handling always follow normal good hygiene practices.

Protection: Use eye protection. Rubber or plastic gloves should be worn where repeated contact occurs and a

face mask worn when working in confined spaces.

First Aid: Eyes - Flush eyes with water for 15 minutes. Seek immediate medical attention.

Skin - Wipe off and wash with soap and water.
Inhalation - Remove to fresh air.

Kerosene and Gas oil fuels (Mineral oils)

Known Hazards: The effect of mineral oils on the skin vary according to the duration of exposure and the type of oil.

The lighter fractions remove the protective grease naturally present on the skin, leaving it dry, liable
to crack and more prone to damage by cuts, abrasions and irritant chemicals.
Skin rashes (Oil acne) most often on arms, but also on any part of the body in contact with oil or
oily clothing.
Contact with fuel oils can cause dermatitis.

Precautions: Avoid as far as possible any skin contact with mineral oil or with clothing contaminated with

mineral oil.
The use of a lanolin-based barrier cream is recommended, in conjunction with regular washing with
soap and rinsing with water to ensure all oil is removed from the skin.
Take care to prevent clothing, especially underwear, from becoming contaminated with oil.
Do not put oily rags or tools in pockets, especially trouser pockets.
Have first-aid treatment at once for an injury, however slight.
Do not inhale any vapours from mineral oils.

Combi V3, Combi Max and Vortex Combi models

62

16 - EC DECLARATION OF CONFORMITY

We declare that the Combi 70 V3, Combi 90 V3, Combi Max, Vortex Combi 26 and Vortex Combi 36 Oil Boilers
equipped with Riello RDB burner approved to EN 267: 1991 satisfy the requirements of the following European
Directives:-

1. 89/336/EEC - Electromagnetic Compatibility Directive
Referred to the generic standards EN 55014: 1993, EN 50082: 1: 1992

2. 73/23/EEC - Electrical Equipment Safety Regulations Directive
Referred to the generic standard NO: 3260: The Electrical Equipment (Safety) Regulations: 1994

3. 92/42/EEC - Hot Water Boiler Efficiency Directive
Referred to the generic standard The Boiler (Efficiency) (Amendment) Regulations 1994
(SI 1994/3083)

63

Combi V3, Combi Max and Vortex Combi models

Grant Engineering (UK) Limited

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

Telephone: [phone] Fax: [phone]

email: [email protected] website: 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 goods sold are subject to our official Conditions of Sale, a copy of which may be
obtained on application.

© Grant Engineering (UK) Limited 2005. No part of this manual may be reproduced by
any means without prior written consent.

Manual compiled and designed by Publications 2000 Tel: [phone]

D189

Complies with the EC Low voltage,
Electromagnetic compatibility and
Boiler efficiency Directives

89/336/EEC
73/23/EEC
92/42/EEC