Chaffoteaux & Maury CORVEC 45 OF User manual

chaffoteaux ltd.
chaffoteau
et lMaury M
C@RVEC45 OF
OF GC No 41 980.30
CORWC 45 BF
BF GC No 41 980.29
installation
servicingrequirements

contents
1)INTRODUCTION
Page3 :TECHNICAL DATA
Pages4.5.6. 7,8,
9, 10, 11 and 12 : INSTALLATION
Pages13and 14 :SERVICING REQUIREMENTS
The CORVEC 45 is r wall mounted. low water content
boiler available in botit balanced flue and open flue ver-
sions. The boiler is rated at 13.2 kW. 10.3 kW, or 7.3 kW
(45,000 Btu/h, 35.000 Btu/hor 2.5.000 Btuih) heat outputs.
The boiler is designed for use with Natural Gas only,
unlessotherwise stated.
A pump must be installed in the water circulation system
irrespective of whether the system is of the open or seaied
Pages15 and 16 : FAULT FINDING CHART
type.
The CORVEC 45 balanced flue version is supplied in two
Page17 :SHORT LIST
cartons, one containing the boiler and the other containing
the balanced flue set. The CORVEC 45 open flue version is
supplied in one carton.
CORVEC 45 BF
A
112
B 305
C 250
D 100
E
333,s
F
606,s
G 50
H
205
I 611,s
J I Ew 51
I eau
32,5
Ii 257,5
CORVEC 45 OF
A 186
B
80
C 323,5
D 117
E
426
F 107
G 623
H
63
I 219,5
L
---------I
I I
I
h B cf
L ----W-B J

technical data
HEAT OUTPUT HEAT INPUT SETTING PRESSURE
kW Btu/h kW Btu/h mbar in w.g.
13,2 45,000 17.0 58,000 10.2 4.1
10.3 35,000 13.4 45,750 6.6 2.6
773 25,000 9.6 32,750 3.5 1.4
N.B. These boilers are supplied with the 10.3 kW (3.5,OOOBtu/h) output restrictor fitted.
RESTRICTOR SIZE
mm dia
3.7
3.0
2.3
CLEARANCE FOR INSTALLATION AND SERVICING
Balancedflue version : Open flue version :
Sides . . . . . . . . . . . . . . . . . . . . . . . . .25n~n(l ins)
Sides . . . . . . . . . . . . . . . . . . . . . . . . . .76mm(3ins)
Top . . . . . . . . . . . . . . . . . . . . . . . . . .76mm(3 ins) Top . . . . . . . . . . . . . . . . . . . . . . . . . . .76mrn(3ins)
Bottom . . . _. . . . . _. . . . . . . . . . . . . 127 mm (5 ins) Bottom. _ . . . . . . . . . . . . . . . . . . . . . . 127 mm (5 ins)
Front . . . . . . . . . . . . . . . . . . . . _. 600 mm (23.6 ins)
Front . . . . . . . . . . . . . . . . . . . . . . .600 mm(23.6 ins)
FLUE CONNECTION
Balanced flue version : Open flue version :
Flue set requires a hole in the wall 205 mm high x 305 mm Requires a nominal 100 mm (4 in) flue pipe. No split collar
wide (8 ins x 12 ins). is required. Draught diverter is integral.
GAS CONNECTION : l/2 ins BSPTaper Male (R l/2)
WATER CONNECTIONS : Flow : 314 ins BSPon left hand side of boiler viewed from front.
Return : 314 ins BSP
The open flue version hasmale threads (R 3/4), the balanced flue, female threads (Rc 3/4).
MINIMUM WATER FLOW RATE : 610 L/h (2.24 gal/mm).
MINIMUM STATIC HEAD AT BOILER : 300 mm (1.Oft) Seesection 5.
MAXIMUM STATIC HEAD AT BOILER : 30 Metres (98 ft).
ELECTRICAL CONNECTIONS : None on the boilers (all control via pump etc...)
DIMENSIONS
Balanced flue version :
612 mm high x 334 mm wide x 255 mm deep
(24insx 13.1 insx 10.0 ins)
Open flue version :
626 mm high x 324 mm wide x 220 mm deep
(24.6 ins x 12.75 ins x 8.7 ins)
WEIGHT : 14.3 kg - 31.5 lbs
WATER CAPACITY :0.58 litres - 1.02 pints
I
A 10 blade Chaffoteaux burner is used fitted with 1.13 mm dia injectors. The non-adjustable permanent pilot is manually ._
ignited by a piezo ignitor. The flow temperature is controlled by a non-adjustable thermostat at a nominal 820 C (1800 F).
3

installation
3) INST.ALLATION REQUIREMENTS
3.1. General
The installation of the boiler must be in accordance with
the Gas Safety Regulations, Building Regulations. I.EE.
Regulations and the Byelaws of the local Water Under-
taking. It should be in accordance also with BS Codes of
Practice and the British Gas Publication, as specified
below. and any relevant requirements of the local Gas
Region and Local Authority.
3.2. Location
The position chosen for the boiler should permit the
provision of a satisfactory flue termination. The position
should also provide adequater space for servicing and air
circulation around the boiler.
Where installation will be in an unusual position. special
procedures may be necessary, and BS 5376 : 2 gives detai-
led guidance on this aspect.
A cupboard or compartment used to enclose the boiler
must be designed and constructed specifically for this
purpose. An existing cupboard or compartment may be
usedprovided that it is modified for the purpose.
Details of essential features of cupboard/compartment
design are given in BS 5376 : 2.
3.3. GasSupply
The gas installation should be in accordance with CP
331 :3.
The meter to be used must be of adequate capacity to
meet the total gasload, i.e. boiler plus other gasappliances.
Ensure that the pipework from the meter to the boiler
is of adequate size. Do not use pipes of a smaller size
than the boiler gasconnection.
The complete installation must be tested for soundness
asdescribed in the above Code.
3.4. Flueing
Detailed recommendations for flueing are given in
BS544O : 1.
The following notes are for general guidance only.
3.4.1. Balanced Hue Version
The boiler must be installed so. that the flue terminal
dischargesdirectly into the external air.
Termination should be on a clear expanse of wah : the
terminal being preferably not less than 600 mm (2 ft)
from a comer. recessor projection.
DO NOT install the terminal :
(a) Within 300 mm (1 ft), measured vertically, from the
bottom of an openable window, air vent or any
other ventilation opening.
(bj Lessthan 300 mm (I ft) from ground levei.
(c) Lessthan 600 mm (2 ft) from any surface facing the
terminal.
(d) Immediately beneath eavesor a balcony.
Where the terminal is less than 2 m (6.6 ft) above the
level of any ground. balcony, flat roof or place to which
people have access, the terminal must be protected by a
guard of suitable material.
Where a terminal guard has not been supplied (optional
extra) with the boiler. one may be obtained from Chaffo-
teaux Limited.
The air inlet/products outlet duct and the terminal of
the boiler should be no closer than 50 mm (2 in) to com-
bustible material. Detailed recommendations on protection
of combustible material are given in BS 5440 : 1.
3.4.2. Open Flue Version
The boiler should be sited such that the maximum possible
length of the flue system can be contained within the
building and that the route of the flue risescontinuously to
the terminal and is asdirect as practicable.
Where possible 600 mm (2 ft) of flue pipe should rise
vertically from the draught diverter connection before
the useof any bends or elbows.
Horizontal or shallow angle runs, right angled bends and
mitred elbows should be avoided.
Where an existing brick chimney is to be used, it should
be swept thoroughly before connection of the new boiler,
and consideration should be given to lining the chimney.
An approved British Gas terminal must be fitted and the
terminal sited at the level of the adjacent roof edge, and
where possible above the ridge line. The flue must not be
terminated at or adjacent to a wall face.
3.5. Air Supply
Detailed recommendations for air supply aire given in BS
5440 :2.
The following notes are intended to give general guidance.
3.5.1. Balanced Flue Version
The room in which a balanced flued boiler is installed
does not require a purpose provided air vent.
Where a balanced flued boiler is installed in a cupboard
or compartment, air vents are required (for cooling pur-
poses) in the cupboard or compartment at high and low
level. These air vents may communicate with a room or
direct to outside air.
The minimum effective area requirement of cupboard/
compartment air vents are asfollows.
Position of
air vents Air from Air direct
room from outside
High Level
Low Level
210 cm2 105 cm2
(32 in2) (16 in2)
10.5cm2210 cm2
(32 in2) (16 in2)
Note - Both air vents must communicate with the same
room, or must be on the samewall to outside air.
n

installation
3.5.2. Open Flue Version
3.5.2.1. Room or internal SpaceAir Supply
Where the boiler is to be installed in a room or internal
space. the boiler requires the room or internal spacecon-
taining it to have a permanent air vent. This vent must be
either direct to outside air or to an adjacent room or
internal space which must itself have a permanent air vent
of at least the samesizedirect to outside air.
The minimum effective area of the permanent air vent (s)
is related to the maximum rated input of the boiler and
should be 43 cm2 (6.6 in2 ).
3.5.2.2. Cupboard or Compartment Air Supply
Where the boiler is to be installed in a cupboard or com-
partment permanent air vents are required (for combustion,
flue dilution and cooling purposes) in the cupboard or
compartment at high and low level. These air vents must
either communicate with a room or internal space or be
direct to outside air.
The minimum effective areas of the permanent air vents
required in the cupboard or compartment are specified
below and are related to the maximum rated heat input
of the boiler.
High
I
150 cm2 75 cm2
Level 23 in2 11.5 in2
LOW
Level 300 cm2 150 cm2
46 in2 23 in2
Note : Both air vents must communicate with the same
room or internal space or must both be on the same wall
to outside air.
Where cupboard or compartment air vents communicate
with a room or internal space, the room or internal space
must itself have a permanent air vent (s) as specified in
3.5.2-l.
3.5.3. Effect of an Extract Fan
If there is any type of extract fan fitted in the premises,
there is a possibility that if adequate air inlet area from
outside is not provided, spillage of the products from the
ioiler flue could occur when the extract fan is in operation.
Where such installations occur, a spillage test asdetailed in
BS 5440 : 1 must be carried out and any necessary action
taken.
3.6. Water Circulation Systems
Open or sealed type central heating systems should be in
accordance with the reievant recommendations given in
BS 5376 : 2. BS 5449 : 1 (for smallbore or microbore
systems) and the British Gas publication entitled “Ma-
terial and Installation Specifications for Domestic Central
Heating and Hot Water”.
Hot water systems should be in accordance with the rele-
vant recommendations given in CP 342 : 1 and the above
mentioned British Gaspublication.
3.7. Electrical Supply
The CORVEC 45 boiler has no electrical connections,
but all wiring external to the boiler must be in accordance
with the 1-E-E.Regulations.
For external wiring instructions, see 4.6. Electrical Con-
nections.
4) INSTALLATION OF BOILER
4.1 General
A vertical flat area is required for the boiler as follows.
Balanced Flue Version - 384 mm wide x 8li mm high
(15.1 ins x 32.0 ins).
Open Flue Version - 476 mm wide x 829 mm high
(18.75 ins x 32.6 ins).
Above dimensions include the necessary clearancesaround
the boilers for caseremoval and for air movement.
4.2. Flueing
4.2.1. Balanced Flue Version
The standard flue set supplied with the boiler is suitable
for walls having a thickness of 75 mm to 355 mm (3 in to
14 in). (Flue sets for walls of thickness up to 610 mm
(24 in) are available to special order).
Using the boiler as a template determine the position
for the flue duct. The following procedure should now
be followed.
(a) Prepare the Wall
Cut a hole in the wall which measures 205 mm
high x 305 mm wide (8 in x 12 in). If the hole is
cut accurately, there is no need to line the hole,
since the wall liier make a satisfactory seal.
(b) Prepare the Parts
Cut the wail liner to the same length as the wall
thickness. Cut the flue duct to the same length,
plus 80 mm (3/4 in).
(c) Fit the Wall Liner (fig. 1) (seepage6).
Position the wall liner in place. Ensure that the
liner is square and horizontal. and that the flange
is flush, with the inside face of the wall. With the
liner fvted in place, make good the external and
internal walI surfaces around the liner with cement.
5

installation
4.2.2. Open Flue Version
The CORVEC 45 open flue version has a draught diverter
outlet suitable for a nominal 100 mm (4 in flue pipe).
The flue should be installed in accordance with the requi-
rements of BS 5440 : 1.
43. Fl-ITING THE BOtLER
Hang the boiler on the wall bracket and mark the positions
of the two bottom fiiing holes. Drill and plug the wall.
Rehang the boiler and screw m position.
Connect the flue to the draught diverter outlet making a
good seal between the spigot and flue pipe.
43.1. Balanced Flue Version 4.4. Gas Connections
Pull off gas control knob. Remove the screw below the The gas service tap must be fitted as in fig. 5. A 15 mm
gas control knob and the two screws top and bottom. (l/2 in), gas supply must be used from the meter outlet
Remove the front cover by pulling forwards. to the boiler.
On later models the flue bend is produced in the cast
aluminium. The Installation instructions should therefore
read, remove the flue bend from the top of the heat
exchanger (two screws and clip or clips) and on re-positio-
ning the flue bend replace with the two screws and clip or
clips.
Fix the top bracket to the rear boiler case,using the screws
provided (fig. 2). Using the boiler as a template, mark all
three i’l.v.i!jgholes (A fig. 3). Drill and plug the wall.
4.5. Water Connections
The water flow pipe is on the left hand side of the boiler
and the water return pipe on the right as indicated in 2.
TECHNICAL DATA.
At this stage the terminal may be fitted from within the
building, d required. by passing it through the wall liner
before fitting the boiler to the wall. TAKE CARE NOT
TO ALLOW THE TERMINAL TO FALL. Attach the
chains onto the hooks inside the wall liner (fig. 4). For
wails between 3” and 6” thick screw the terminal to the
walI face. Attach the self adhesive foam gasket to the
flat surface or the boiler around the air inlet spigot on the
back of the boiler. Pull off the protective paper whilst
sticking down the gasket. Lift the boiler into position
with the air inlet spigot locating in the wall liner. Secure
the boiler to the wall using the screwsand washersprovided.
If not previously fitted, fit the terminal form the outside.
Slide the flue duct through the wall liner and engageit in
the terminal by at least 25 mm (1 in) and fully onto the
flue bend. The duct may have to be cut to lenght. Repiace
the flue bend and secure with the two screws and clips.
Ensure that the seal between the heat exchanger and the
flue bend is made evenly and securely.
4.3.2. Open Flue Version
The boiler is attached to the wall by a bracket at the
top ot’ the boiler and by two screwsat the bottom.
The balanced flue version has a built-in facility for top
connection. Where top connection is used. remove the
plugs from the two top connections and transfer them
to the bottom.
Where bottom outlet connections are used, the blanked
off top outlet connections can be used as air vents when
commissioning.
The open flue version has no purpose made facility for top
connections. but recesses are provided on both sides of
the boiler frame to allow pipes to rise within the boiler
dimension as shown in 2. TECHNICAL DATA.
1 9
-J,
-- “,
D
Fig. 2
Using the dimensions detailed in 2. TECHNICAL DATA.
mark the position of the furing holes for the wall mount-
ing plate ensuring adequate space for connection to the
flue pipe.
Remove the boiler cover by pulling off the gas control
knob and removing the screw below it. Pull the bottom
of the cover forwards then lift off.
Fig. 1 Fig. 4

installation
4.6. Electrical Connections
The COKVEC 45 has no electrical connections and all
external electrical controls should be wired to control
the circulating pump.
Most normal pumped primary controi schemescan be used.
including non-electrical heating and hot water controls.
The following diagrams show typical control schemesusing
electrical controls only.
fig 6 Hot Water only
Pump, Time Clock and Cylinder Thermostat
fig 7
fig 8
fig 9
2 10
fig 11
fig 12
Heating only
Pump, Time Clock and Room Thermostat
Hot Water and Heating
Pump Programmer. Room/Cylinder Thermostat
and Flow Share Valve
Hot Water and Heating
Pump, Programmer, Room/Cylinder thermostats
and two Motorized Valves
Hot Water and Heating
Pump, Time Clock and Non-Electrical Hot
Water and Heating Controls
Hot Water and Heating
Pump. Time Clock, Non-Electrical Hot Water
Control and Electrical Heating Control
Hot Water and Heating
Pump, Time Clock. Non-Electrical Heating
Control and Electrical Hot Water Control
TIME CLOCK CYLINDER PUM?
THERMOSTAT
ROOM THERMOSTAT PUMP -
The following diagrams show typical control schemes
using electrical/nonelectrical controls.
TIMECLOCK PUMP-
TIME CLOCK
CYLINDER THERMOSTAT
It is not normally possible to usefull programming facilities
when using a mixture of electrical and nonelectrical
controls, but some nonelectrical hot water controls are
now available with an external micro-switch which would
allow the scheme as in fig. 11 to be fully programmed.

installation
j) WATER CIRCULATING SYSTEM
5.1. General
The CORVJX 45 is a low water content boiler designed
only for use with fully pumped systems. It may be used
with open or sealed systems. all safety controls excluding
the pressure relief vaive being incorporated in the boiler.
The thermostat is set to give a nominal 820 C (1800 F)
flow temperature and is not adjustable. Thermostatic
control must be fitted to the cylinder and heating circuits.
5.2. Control Schemes
The boiler does not incorporate electrical controls or
connections. the primary control being provided by the
pump. the operation of which will light the boiler, provi-
ding that there is a minimum flow of 575 l/h (2.1 gal/ml.
Most normal pumped primary control schemes can be
used including thermostatic radiator and cylinder valves.
When using motorized valves. the system control should
be designed to switch off the pump when ali circuits
are satisfied.
For details of wiring and of control schemes. see 4.6.
Chaffoteaux Limited should be consulted where tech-
nic+ assistanceis required.
5.3. Isolating Valves
Two isolating valves should be fitted adjacent to the boiler
to allow full servicing facilities. Where the circulating pump
is adjacent to the boiler and is provided with isolating
valves, it is only necessary to fit one isoiating vaive in the
boiler flow. Fig. 13 shows a typical pipework arrange-
ment .
5.4. Circulating Pump
‘Ihe circulating pump should be fitted in the return as
shown in fig. 13, and shouid be sized to overcome the
hydraulic resistance of the boiler and system. The boiler
requires a minimum flow rate of 610 l/h(2.24gai/min) for
its correct operation and at this flow has a resistance
of 2.9 metres ( 9.5 ft). Seegraph.
I I I i
IIIIIIIII
:-4
4
T3
3
2 2
D
0
I1
100 200 300 400 500 600 700
Flow rate Litres/h
Where it is impossible to fit the pump in the return. It
may be fitted in the flow as shown in fig 14, providing
that there is a minimum of 3.2 metres (IO.5 ft) static
head between the water level in the feed and expansion
tank and the top of the boiier casing.
5.5. System By-Pass
A valved system by-pass as shown in figs 13 and 14 may
be required to ensure adequate water flow through the
boiler. The by-pass should be a 15 mm ( l/2 in) pipe with a
suitable balancing valve.
5.6. Automatic Air Separators
Chaffoteaux Limited strongly recommend the inclusion
of a British Gas accepted automatic air separator in the
system asshown in fig 13 and 14.
Where an air separator is not fitted. the open vent pipe
should rise continuously from the pump inlet and the
common return be introduced at right angles to this pipe.
The preferred arrangement is shown in fig 15.
5.7. Open Systems Only
5.7.1. Cylinder
The domestic hot water cylinder used with the CORVEC
45 must be of the indirect coil and high recovery type.
Flow and return pipework to the cylinder should be in
22 mm (3/4 in) pipe.
5.7.2. Feed and Expansion Tank
The feed and expansion tank should be connected as
shown in figs 13 or 14 and should not mounted closer
than 9 ins to a ceiling ro allow access to the ball valve.
The minimum static head for the CORVEC 45 should be
300 mm (1 .Oft) for the pump on the return (fig. 13)
and 3.2 metres (10.5 ft) for the pump on the flow
(fig. 14).
5.8. Sealed Systems Only
5.8.1. Safety Valve
A safety valve shall be fitted close to the appliance on the
flow pipe by a horizontal or a vertically upward connection.
Only safety valves set to operate at 3 bar shall be used ;
they shall be sopositioned. or any dischargepipe soarranged,
that discharge of water or steam from the valve cannot
create a hazard to occupants of the premises or cause
damage to electrical components and wiring.
5.8.2. PressureGauge
A pressure gauge covering at least the range 04 bar (O-60
lb/in21 shall be fitted to the system adjacent to. and visible
from. the fdling point.
8

installation
.....
.....
II
.....
....
.....
E
E
e
Fig. 13
r
AIR
SEPARATOR
PUMP \
6 ins
v
Fig. 14
TO BOILER PUMP
Fig. 15
9

installation
5.8.3. Expansion Vessel
(9
A diaphragm type expansion vesselshall be fitted (ii) The nitrogen or air charge pressure of the expan-
by a connection to the inlet side of the circulating sion vessel shall be not less than the hydrostatic
pump. in a manner laid down in the vesselmaker’s head (height of the top point of the system
instructions (see fig 16 for illustration of recom- above the expansion vessel).
menced system layouts). The expansion vessel
shall be capable of accepting water up to at least (iii) The expansion vessel shall be sized in accordance
62.5 % of its volume without damage. with the following Table.
Air or nitrogen charge
pressure(bar*, gauge)
Pre-pressurisation
pressure(bar*. gauge)
System Volume
Litres Gallons
None
Expansion Vessel Volume (litres)
OS 1.o
170 None 1s
20 4.4 1.4 2.4 1.8 3.3
40 8.8 2.8 4.9 3.7 6.6
60 13.2 4.2 7.3 5.4 9.8
80 17.6 5.6 9.8 7.3 12.3
100 22.0 7.0 12.2 9.1 16.4
120 26.4 8.4 14.6 11.0 19.7
140 30.8 9.8 17.0 12.8 23.0
160 35.2 11.2 19.4 14.6 26.2
180 39.6 12.6 21.9 16.4 29.5
200 44.0 14.0 243 18.2 32.8
* 1bar 14.5 lb. f/in2 (Approx. 1atmosphere or 34 feet head of water).
Where a vesselof the calculated size is not obtainable. the next available larger size should be used.
For the purpose of the above calculation, the volume of the system shall be determined asaccurately aspossible using manufac-
turers’ data as appropriate. Alternatively the volumes given below may be used to give a conservative estimate of the system
volume :
Low water capacity boiler . . . . . . . . . . - . . . . . . . . . . . . . . . . . _. . . . . . . . . . 0,8 litres (0.18 gallons)
Small bore pipework . . . . . . . . . . . . . _. . . . . . . . . . . . . ________. . . _ _. . _ 0.3 litres (0.07 gallons) per 0.292 kW
(1000 Btu/h) of system output.
Microbore pipework . . , . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . _ 7 litres ( 1.5 gallons)
Steel panel radiators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _. _. ___. __. __. 2.3 litres (0.5 gallons) per 0.292 kW
(1000 Btu/h) of system output.
Hot water cylinder . _. __. . ___. . . . . . . ___. _. . . . . . . . . . . . . . _. . . 2 litres (0.44 gallons)
If a system if extended, an expansion of increased volume may be required unless previous provision has been made for the
extension.

installation
PUMP ON THE FLOW
Fig. 16
PUMP ON THE RETURN
5.8.4. Hot Water Storage Cylinder
The hot water cylinder shall be the indirect coil type
which is suitable for the system pressure.
5.8.5. Make-Up System
Provision shall be made for replacing water lost from the
system either :
(i) From a make-up vessel or tank mounted in a
position higher than the top point of the system.
and connected through a non-return valve to
the system on the return side of the hot water
cylinder or the return side of all heat emitters.
or.
(ii) Where access to a make-up vessel wouid be
difficult. by pressurisation of the system.
5.8.6. *MainsConnection
There shall be no connection to the mains water supply
r to the water storage tank supplying domestic water.
even through a non-return valve. without the approval
or the local Water Authority.
5.8.7. Filling Point
The system shall be fitted with a filling point at low level.
which shall have a stop valve to BS 1010. a test cock. an
anti-vacuum vaive and a non-return valve approved by the
Nationai Water Council in this order from the system ta the
mains.
5.8.8.
Pipework
Pipework should be of copper : small bore or microbore
with capulary or compression jointing to a high standard.
Leak sealant shall not be used in the system.
8.9. Feed and Expansion System
Except as provided for above. the expansion cistern and
cold feed required for open systems shall not be fitted
to seaiedsystems.
DIAGRX?IS SHOWING
SYSTE>I LAYOUT
1 . Expansion vessel
2 _ Pressure gauge
3 - Filling pomt
4 _ Drain cock
5 . Air release point
6 - Safety valve
7 - Top-up bottle
5.9. Inhibitors
Chaffoteaux Limited do not generally recommend the
inclusion of an inhibitor with heating and hot water systems.
utilizing the CORVEC 45 boilers. It is. however. appreciated
that the specification for a new installation may require the
addition of an inhibitor and the following are the appliance
manufacturers recommendations.
(i) Useonly a British Gasapproved inhibitor.
(ii) Use only the quantities specified by the inhibi-
tor manifacturer.
(iii) Add the inhibitor only when the system has all
air removed.
6)COMMISSIONINGANDTESTING
6.1. Electrical Installation
Checks to ensure electrical safety should be carried out by a
competent person.
6.2. GasInstallation
The whole of the gas installation. including the ‘meter.
should be inspected and tested for soundnessand purged in
accordance with the recommendations of CP 331 : 3.
6.3. Water Circulation System
6.3.1. Open System Only
The whole of the system should be fitted and thorou-
ghly flushed out with cold water without the pump in
position. Ensure that all valvesare open.
With the pump fitted. the system should be filled and
air locks cleared. The boiler water section can be vented
if nerlessary by unscrewing the knurled nut on the dram
valve (see 6.6.) and the top outlet plugs (see 4.5.). Vent
all radiators and check for water soundness.
Light the boiler asdetailed in 6.4.
The water system should be heated to maximum wor-
king temperature and examined for water soundness.
Both gas and water should then be turned off and the
water system rapidly drained while still hot.
11

installation
The system should again be filled, cleared of air locks
and examined for water soundness.
Add inhibitor to the system if required in the specifica-
tion (see 5.9.)
6.3.2. SealedSystem Only
The whole of the system should be ffied and thoroughly
flushed out with cold water without the circulating pump
in position. Ensure that alI valves are open. (The system
must be filled with water either from a sealedsystem filler
pump with a break tank. or by any other method approved
by the local Water Undertaking)-
With the circulating pump fitted, the system should be
filled and air locks cleared until the pressure gaugeregisters
1.5 bar (21 .S Ibf/in2). (The boiler water section can be
vented if necessary by unscrewing the knuried nut on the
drain valve, see6.6). Vent all radiators and check for water
soundness.
Manually raise the water pressure to ensure that the safety
valve lifts. This should occur within f 0.3 bar (’ 4.3
Ibf/i.n2) of the preset lift pressure. i.e. 3 bar (43.5 Ibf/in2).
Release water from the system until the initial system
design pressure is attained, taking into account any diffe-
rence in height between the pressuregaugeand the point at
which the pressure vesselis connected.
Light the boiler asdetailed in 6.4.
The water system should be heated to maximum working
temperature and examined for water soundness. Both
gas and water should then be turned off and the water
system rapidly drained whilst still hot.
The system should again be filled, cleared of air locks
and adjusted to the initial system design pressure. Any
set pointer on the pressure gauge should be set to coincide
with the indicating pointer- Examine for water soundness.
Add inhibitor to the system if required in the specifica-
tion (see 5.9.).
6.4. Lighting the Boiler
The following procedure should be followed :
(4
(b)
Cc)
‘N.B.
(4
(e)
0-l
(ia
Check that the gasservice tap is open.
Replace the gascontrol knob.
Turn the gas control knob in an anticlockwise
direction which will automatically light the pilot.
It may be necessary to wait a few moments for
gasto reach the pilot.
Wait 15 seconds, then turn the gascontrol knob
slowly, fully, in an anticlockwise direction. If
pilot is extinguished for any reason, wait 3 minutes
before lighting.
The boiler is now ready to operate and will light
when water is pumped through.
Test for gas soundness using sense of smell and
leak detection fluid.
Check and, if necessary, adjust the gas rate as
detailed in 6.5.
6.5. Gas Rate Adjustment
The boiler is not fitted with a governor.
To obtain the required output, it may be necessary to
change the restrictor situated in the burner manifold
(fig. 17). To alter the heat output remove the pilot supply
tube and the two screws securing the burner manifold to
the burner assembly. Replace the restrictor with the required
size as detailed in TECHNICAL DATA. Replace the burner
manifold and pilot tube.
Since the opening of the gas valve depends upon water
flow rate, make the above adjustment when all the air
is removed from the system and all radiator valves are
fully open.
Mark the data badge in the line “SET TO” (against output)
to which the boiler has been adjusted- The data badge is
situated inside the case.
6.6. Balancing the System By-Pass
The system by-pass should be balanced as the final part
of commissioning.
1. A system by-Pass is not required for the safe
operation of the boiler, which will automatically
shut down if the flow rate drops below 500 l/h
(1.85 gpm). If however the system may berequired
to be used with a large reduction of heat output at
certain times i. e. a reduced number of radiators,
then a 15 mm system by-pass should be used. This
should be fitted as shown in diagram 6. To set the
system by-pass, close the by-pass valve and turn
off the required number of radiators to suit the
customer’s needs then open the by-pass until the
boiler lights.
2. Check system on hot water only. Open bypass
further if necessary to obtain correct operation.
6.7. Draining the Boiler
Close the valves in the pipework connecting the boiler
to the system (fig. 13 or 14). Drain the boiler unscrewing
the knurled nut on the drain valve.
7) BOILER CASE ASSEMBLY
7.1. Balanced Flue Version
Fit front cover and refit securing screws at the top and
bottom and immediately under the gascontrol.
Push on gascontrol knob.
7.2. Open Flue Version
Fit case and refit securing screw immediately under the
gascontrol. Push on gascontrol knob.
Hand the USERS INSTRUCTIONS to the user for reten-
tion and instruct in the operation of the boiler.
Advise the user of the precautions necessary to prevent
damage to the system and to the building in the event of
the system remaining inoperative during frost conditions.
Finally advise the user that, for continued efficient and
safe operation of the boiler, it is important that adequate
servicing is carried out at regular mtervais recommended
by the local GasRegion.

servicingrequirements
9) SERVICING REQUIREMENTS
For efficient and trouble free operation it is important
that the CORVEC 4.5 receives regular maintenance. The
following schedulesare recommended.
Before commencing any work, turn off the gasat the gas
inlet tap and isolate the boiler from the water circulating
system (see 5.3.). Ensure that the electricity supply to the
system is switched off. Remove the front cover asdetailed
in 4.3.1. or 4.3.2.
9.1. Annual Service
9.1.1. Clean the Burner (fig. 17).
Unscrew the pilot tube ciamping screw A. and remove
the clamp and tube. Remove the burner manifold by
unscrewing fiuing screws B. Pull burner head assembly
forward to remove. taking care not to trap the thermo-
coupie or ignitor wires. Inverr the burner head and clean
by brushing. Replace in reverse order ensuring that the
burner head is correctly located on the spigot at the rear,
and that the gasket between the burner manifold and gas
section is in place.
9.1.2.
Clean the Heating Body
Remove the flue bend on balanced flue versions asdetailed
in 4.3.1.
Drain the boiler asdetailed in 6.7.
Remove burner asdetailed in 9.1 .I.
Remove the two wires from the fusible link overheat
.arrier taking care not to lose the nuts and washers.
B.F. Model - Remove the screw holding the bottom of the
heating body skirt ot the rear case.
O.F. Model - Slacken the four screws holding the clamping
plate of the heating body to the rear case.
Remove the screw fixing the top of the
heating body to the draught diverter.
Release the two union nuts joining the heating body legs
to the water section.
Remove the heating body.
Clean the heating body by brushing with hot water and
detergent. Do not attempt to clean the internal water-
ways of the heating body without prior consultation
with the manufacturer. Before replacing heating body,
see 9.1.3. Replace in reverse order, using new washers
where appiicable.
9.13. Clean the Pilot Assembly, Thermocouple and
Spark Electrode
Unscrew the pilot tube clamping screw and remove the
clamp and tube. Blow through the tube to remove any
dust. Remove the burner asin 9.1 .l.
Unscrew the knurled outer ring of the pilot burner (B -
fig. 18).
Unscrew the pilot body (C - fig 18) with a 15 mm spanner.
It may be necessary to remove the heating body (9.1.2.)
if this has already been replaced.
Clean the pilot body by blowing or washing. Do not clean
the holes with a wire.
Disconnect the thermocuple from the overheat terminal
stud. With a 7 mm box spanner. unscrew the nut holding
the thermocouple into the gas section (D fig. 19). Thread
the thermocouple and wire up through the gas section.
Clean the end of the thermocouple by brushing.
Remove the spark electrode fig screw (E - fig 19)
with a cruciform head screwdriver.
Pull off the electrode cable from the piezo ignitor.
Lift the electrode out of the gas section. Clean the end
of the electrode by brushing. Blow any dust out of the
gassection.
Replace all parts in reverse and ensure that the slot in
the electrode cable connector is vertical when pushed
onto the piezo ignitor. The pilot flame is non-adjustable.
When burning correctly, the flame should be 3/16’*to1/4”
high, reaching half way up the explosed part of the thermo-
couple.
9.1A. Clean the Gas Filter
Unscrew the union nut attaching the gas inlet tap to the
appliance. Lower the union nut and withdraw the filter
which also acts as a washer. Clean the filter by blowing
dr washing in water. Do not use any solvents. Replace
in reverse order.
Fig. 17 Fig. 18
13
Fig. 19

servicingrequirements
9.1.5. Clean the Thermostat Capsuie
Drain the boiler asdetailed in 6.7.
Using a 14 mm spanner. remove the thermostat housing
cover taking care not to loose the spring. Remove the
thermostat capsule and clean with soap and water. Replace
in reverseorder.
9.1.6. Clean the water filter
Dram the boiler as detailed in 6.7. The water filter is
situated in the inlet to the venturi. Unscrew the union
nut on the flow pipe from the heating body at the venturi
(fig. 20). Remove the fdter, clean in water and replace.
9.2. Three Yeariy Service
9.2.1. Clean Burner. Heating Body, Pilot Assembly and
Thermocouple.
Asdetaikdin9.1.1.-9.1.3.
9.2.2. Replace the Gas Filter
As detailed in 9.1.4.
9.2.3. Replace the Diaphragm
Drain the boiler asdetailed in 6.7.
Unscrew the four water union nuts (A -- fig. 21) on the
water section.
Unscrew the six screws (B - fig 21) holding the water
section to the gas sectionNote the relative positions of the
gas and water sections and the two halves of the water
section. Unscrew the two screws holding the water section
clamp.
Remove the water section complete with the diaphragm
and bearing plate. Separate the top and bottom halves of
the water section by removing the eight screws.
Remove diaphragm and discard. Wash out water section.
Replace with a new diaphragm fitted and the bearing plate
positioned on the top of the diaphragm.
Reassemble with the components in their original relative
positions.
Fig. 20
9.2.4. Clean the Gas Valve
Remove the burner asin 9.1.1.
Disconnect the thermocoupie from the overheat terminal
stud and pull off the electrode cable from the piezo igniter.
Remove the four fiving screws fastening the top of the
gas section to the base. Also the two screws at the back
holding it to the rear case.
Lift the gassection top off the base.
Remove the gasvalve spring.
Lift out the gasvalve.
Do not attempt to further dismantle the valve assembly.
Clean the valve seating and replace the gas valve facing
rubber if necessary.
Replace in reverseorder.
10.1 To replace the Thermo-electric Valve
Remove the thermocouple nut.
Unscrew cap ftom the side of the gas section and with-
draw the thermoelectric valve. Replace if necessary.
10.2 To replace the Fusible Link
Remove the two nuts securing the thermocouple leads to
terminals of the overheat assembly.
Remove clamping disc.
Remove fusible link.
Replace the fusible link. When forming the wires to shape,
avoid bending them close to their entry into the fuse.
Uselong nosed pliers to support the wire.
Re-assemblein reverseorder.
10.3. To replace the Piezo ignitor Cartridge
Pull off the electrode lead from the cartridge.
Remove the screw holding the gascontrol cam.
Pull the cam off the spindle.
Remove the two screws holding the retaining plate in
position.
Remove the plate and then the Piezo cartridge.
Replace in reverse order. note the slot in the end of the
electrode cable is vertical when pushed on to the Piezo.
Fig. 21

fault finding chart
FAULT POSSIBLE CAUSE REMEDY
Pilot will not light
Pilot lights with taper but not
with igniter
Pilot goesout
Main burner “lifts”
Gassupply not turned on.
Gassupply pipes not purged of air.
Fusible Link open circuited.
Fusible Link shorting to earth.
Spark electrode wrongly positioned.
Spark from electrode not jumping to thermocou-
ple.
Electrode lead detached from Piezo Igniter.
Electrode leaddamagedcausing local short circuit.
Fauity Piezo Igniter.
Pilot too small, injector blocked.
Thermocoupie/thermoelectric valve fauity, low
MV output.
Thermocouple loose.
Terminal wrongly positioned causingre-circulation.
Flue set wrongly fitted causing re-circulation.
Fusible Link fused.
Fusible iink earthing out.
Securing nuts loose.
Insulation washersfitted incorrectly.
Low meter pressure.
Pilot flame too soft.
1 Re-circulation of flue products.
Terminal badly sited and flue set wrongly assem-
bled.
Terminal not fitted in wall-liner.
Over-gassed.
Check sealingof flue.
Turn on.
Purge.
Replace.
Re-position.
Re-position.
Refit.
Replace.
Replace.
Replace or wash in solvent.
Replace.
Tighten.
Installer to resite boiler.
Fit correctly.
Replace
Refit.
Re-tighten.
Refit _
Gas Region to adjust.
Clean pilot tube or replace pilot
injector. .
Remove flue set and fit correctly.
Refit.
Fit correctly.
Adjust, set to correct gasrate.
Reseal and fit correctly.
15

fault finding chart
FAULT POSSIBLECAUSE REMEDY
Clain burner will not light or
ights at low rate
.
Compiaints of noise
Over-gassed
Low flow rate pump duty not sufficient.
Low flow rate system very restrictive.
Low flow rate. air in system.
Water section spindle bent or dry
Diaphragm split or stretched.
Thermostatnot seating properly.
Gassuppiy insufficient,
Heat exchanger blocked
Pump speed too slow.
Flow and return pipescrossedor plaster. cement in
pipes.
Sludge/s&e in the heat exchanger.
Fauity boiler thermostat.
Water section push rod sticking.
Gasvalve sticking open.
Dirt/swarf on gasvalve facing.
Resistance to water flow.
Water filter blocked.
Venturi blocked.
Wrongly positioned feed and vent _
incorrect inhibitor in system.
Pump noisy or vibrating.
Fit a suitable pump.
Open system by-pass.
Purgethoroughly, fit air separa-
tor if air is persistent or where
convectors are usedasheat emi-
tters.
Replace or grease.
Replace.
Inspect, clean.
Check working pressure 8 ins. wg
at service tap.
Descaieor replace. ’
Adjust.
Rectify.
Check rate, adjust.
Wash/descaieor replace.
Check flow temperature.
Clean.
Clean gasvalve spindle.
Reassembie.
Open restrictive valves.
Clean.
Clear venturi.
Re-position on suction side of
pump.
Inhibitor not recommended -
contact Chaffoteaux Limited.
Replace or refit.

Notes

Notes

Notes

CHAFFOTEAUX LIMITED
Concord House - Brighton Road
Salfords - Redhill
SURREY RHl 5 DX
HORLEY (02934) 72744
xc-4
3r
:-
- .i
ESPOZO