Wall Mounted, Fan Assisted, Room Sealed, Gas Fired
High Efficiency Condensing Boilers
For Technical help or for Service call ...
ALPHA HELPLINE
Tel: 0870 3001964
Nepicar House, London Road,
Wrotham Heath, Sevenoaks,
Kent TN15 7RS
*HEJEID/=I
Service Listed
Alpha CD18SBritish Gas G.C. No. 41 532 13
Alpha CD24CBritish Gas G.C. No. 47 532 19
Alpha CD24SBritish Gas G.C. No. 41 532 02
Alpha CD30SBritish Gas G.C. No. 41 532 14
Alpha CD32CBritish Gas G.C. No. 47 532 21
For use with LPG (Propane) only
Leave these instructions with the User
Page 2
1INTRODUCTION
This supplement is for the LPG model of the boiler; it must be read in conjunction with the 'Installation and Servicing
Instructions' supplied with the boiler and provides the extra information which is particular to LPG.
The Alpha CD24C and CD32C are combination boilers providing both central heating and domestic hot water at mains
pressure. The CD18S, CD24S and CD30S are System boilers providing heating only for sealed central heating systems.
The boilers are designed for use with a fully pumped, sealed and pressurised heating system using only PROPANE gas.
2TECHNICAL DATA
PERFORMANCE - PROPANE GAS
(CAT I3P 3P- G31 - 37 mbar)
Alpah CD18S
Central Heating
Heat Input (H
)kW
s
(Gross)Btu/h
Heat Input (Hi)kW
(Net)Btu/h
Heat Output (Hs condensing)kW
(50°C/30°C)Btu/h
Heat Output (Hi non-condensing)kW
(80°C/60°C)Btu/h
Differential Burnermbar
Pressurein wg
Room sealed
chamber panel
fitted
MAX.
20.3
69 200
18.3
62 400
19.5
66 500
18.1
61 800
3.9
1.56
Gas Supply Pressure (LPG)mbar
in wg
Gas Rate (LPG)m³/h
ft³/h
0.71
25.1
MIN.
5.5
18 800
5.0
17 000
5.3
18 100
4.7
16 050
0.35
0.14
37.0
14.8
0.26
9.2
Alpha CD24C and CD24SAlpha CD24C
Central Heating
Heat Input (H
)kW
s
(Gross)Btu/h
Heat Input (Hi)kW
(Net)Btu/h
Heat Output (Hs condensing)kW
(50°C/30°C)Btu/h
Heat Output (Hi non-condensing)kW
(80°C/60°C)Btu/h
Differential Burnermbar
Pressurein wg
Room sealed
chamber panel
fitted
MAX.
26.4
90 100
24.0
82 000
25.4
86 700
23.5
81 135
6.7
2.7
Gas Supply Pressure (LPG)mbar
in wg
Gas Rate (LPG)m³/h
ft³/h
1.03
36.6
MIN.
18 800
17 100
18 100
16 018
0.16
37.0
14.8
0.42
15.1
5.5
5.0
5.3
4.7
0.4
Domestic Hot Water
Heat Input (H
(Gross)Btu/h
Heat Input (Hi)kW
(Net)Btu/h
Output to Water (Hs)kW
(modulating)Btu/h
Differential Burnermbar
Pressurein wg
Gas Supply Pressure (LPG)mbar
Gas Rate (LPG)m³/h
Flow Rate at 35°C RiseL/min
Specific Flow Rate (D) at 30°C Rise L/min
(Flow rate @ 30K to EN625)gal/min
MAX.
)kW
s
26.4
90 100
24.0
82 000
24.20
82 600
Room sealed
chamber panel
fitted
6.7
2.7
37.0
in wg
14.8
1.03
ft³/h
36.6
9.6
gal/min
2.2
11.2
2.5
MIN.
5.5
18 800
5.0
17 100
4.97
17 000
0.4
0.16
0.42
15.1
CD18/24/30/32 LPG Supplement
2
Page 3
Alpha CD30S and CD32C
Central Heating
Heat Input (H
)kW
s
(Gross)Btu/h
Heat Input (Hi)kW
(Net)Btu/h
Heat Output (Hs condensing)kW
(50°C/30°C)Btu/h
Heat Output (Hi non-condensing)kW
(80°C/60°C)Btu/h
Differential Burnermbar
Pressurein wg
Room sealed
chamber panel
fitted
Gas Supply Pressure (LPG)mbar
in wg
Gas Rate (LPG)m³/h
ft³/h
MAX.
31.1
106 100
28.0
95 550
29.8
101 700
28.0
95 500
4.48
1.8
37.0
14.8
1.2
42.4
MIN.
7.3
24 900
6.6
22 500
7.0
23 900
6.5
22 200
0.4
0.16
0.28
9.9
Alpha CD32C
Domestic Hot Water
Heat Input (H
)kW
s
(Gross)Btu/h
Heat Input (Hi)kW
(Net)Btu/h
Output to Water (Hs)kW
(modulating)Btu/h
Differential Burnermbar
Pressurein wg
Room sealed
chamber
panel fitted
Gas Supply Pressure (LPG)mbar
in wg
Gas Rate (LPG)m³/h
ft³/h
Flow Rate at 35°C RiseL/min
gal/min
Specific Flow Rate (D) at 30°C Rise L/min
(Flow rate @ 30K to EN625)gal/min
MAX.
36.2
123 500
32.6
111 300
32.0
109 200
6.07
2.4
37.0
14.8
1.4
49.4
13.2
2.9
15.4
3.4
MIN.
7.3
24 900
6.6
22 500
6.6
22 500
0.4
0.16
0.28
9.9
2.3GAS SUPPLY
The Alpha CD18S boiler requires a gas rate of 1.3 kg/h (2.8 lb/h) or 2.5 litres/h of liquid gas.
The Alpha CD24 boiler requires a gas rate of 1.9 kg/h (4.1 lb/h) or 3.6 litres/h of liquid gas.
The Alpha CD30S boiler requires a gas rate of 2.2 kg/h (4.7 lb/h) or 4.2 litres/h of liquid gas.
The Alpha CD32 boiler requires a gas rate of 2.53 kg/h (5.6 lb/h) or 4.9 litres/h of liquid gas.
The supply pipes must be capable of delivering this quantity of gas in addition to the demand from any other appliances in the
house. The boilers require at least a 22 mm gas supply pipe, except for the CD18S which requires a 15 mm gas supply pipe.
The complete installation must be tested for gas soundness against leakage.
The local Propane gas supplier should be consulted, at the installation planning stage, in order to establish the availability of
an adequate supply of gas.
3BOILER LOCATION
Installation pipes, cylinders and pressure regulators should be fitted in accordance with BS 5482:1. Bulk tank installation must
comply with the requirements of the Home Office code of practice for the storage of liquefied petroleum gas at fixed installations.
The boiler must not be installed in a room or internal space below ground level, e.g. in a basement or cellar, except where at
least one side is open to ground level.
4INSTALLATION
In addition to the regulations and requirements stated in the Installation and Servicing instructions, the boiler must be installed
in accordance with BS 5482:1 - The Installation of Propane Burning Appliances in Permanent Dwellings.
5COMMISSIONING
The boiler has been tested and factory set for use with Propane gas and it should only be necessary to ensure the correct gas
supply pressure of 37 mbar is available.
CD18/24/30/32 LPG Supplement
3
Page 4
6PARTS LIST
Only the main burner injectors are special to Propane boilers. For other 'Short List Spare Parts', refer to the Installation and
Servicing instructions supplied with the boiler.
Propane components
Main burner injector - CD18S, CD24C, CD24S
Main burner injector - CD32C, CD30S
Qty.
1
1
Type
3.8 mm
4.55 mm
Alpha Part No.
1.012953
1.018202
7SERVICING
When servicing or replacing boiler components follow the procedures as described in the main Installation and Servicing
instructions supplied with the boiler.
Remembering the parts special for Propane boilers and the burner pressures special to Propane boilers given in this leaflet.
DETAILS OF BOILER INSTALLATION
Date of Installation: ......................................................................
Name of Installer: .........................................................................