Boilers: Compare features & prices Worcester Greenstar 34Cdi Classic review

The Greenstar CDi boilers are Worcester's top-of-the-range combination gas boilers for larger homes. Worcester claims that they operate at high efficiency in both heat and hot water mode whereas most combis only manage this when heating. Read our full review to find out whether the boilers live up to these claims and whether the Worcester Greenstar 34CDi Classic is the right boiler for your home. Most importantly, discover whether Worcester gas boilers benefit from good brand reliability.
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Specification criteria Specification
Specification
Fuel type Gas or LPG
Type of boiler Combi
Mounting position Wall-mounted
Heat output band (kW) 30.0
LPG convertible Whether the boiler can be converted to burn liquid petroleum gas. Yes
Heat outputs available (kW) The different sizes (heat output in kW) of the boilers available in this boiler range. 27;30;37;42
Warranty (years) 2
Warranty (parts) Varies according to parts
Warranty (labour) Varies according to parts
Dimensions
Weight (kg) The lift weight for installing the boiler, as stated by the manufacturer. 48.5
Size (HxWxD in cm) Measurements of the boiler excluding any space needed for ventilation or cables. 76x44x36
Boiler volume (litres) Volume of the boiler excluding any space required for ventilation or cables. 120.0
Clearance at the top (cm) A clearance is the space required around a boiler casing to allow safe operation or access for servicing. 3
Left side clearance (cm) A clearance is the space required around a boiler casing to allow safe operation or access for servicing. 1
Right side clearance (cm) A clearance is the space required around a boiler casing to allow safe operation or access for servicing. 1
Clearance at the bottom (cm) A clearance is the space required around a boiler casing to allow safe operation or access for servicing. 20
Front clearance in operation (cm) A clearance is the space required around a boiler casing to allow safe operation or access for servicing. 2
Front clearance for servicing (cm) A clearance is the space required around a boiler casing to allow safe operation or access for servicing. 60
Central heating performance
Minimum heat output (kW; non-condensing) The manufacturers' claimed minimum heating output in non-condensing mode. 7.7
Maximum heat output (kW; non-condensing) The manufacturers' claimed maximum central heating output in non-condensing mode. 30.0
Maximum heat output (kW; condensing) The manufacturers' claimed maximum central heating output in condensing mode. 32.1
Efficiency (% SAP 2009) Measured by an independent laboratory, this is the measured energy efficiency of the boiler, including heat and hot water; it is calculated to an industry standard called SAP 2009. 89.4
SAP winter efficiency (%) Measured by an independent laboratory, this is the measured energy efficiency of the boiler, including heat and hot water; it is calculated to an industry standard called SAP 2009. 90.3
SAP summer efficiency (%) Measured by an independent laboratory, this is the measured energy efficiency of the boiler, including heat and hot water; it is calculated to an industry standard called SAP 2009. 80.2
NOx Emission class The official classification for the emission of the polluting gases NOx. Class 5 is the best class with the lowest NOx emissions. 5
Electricity usage
Electricity usage on standby (W) The amount of electricity used when the boiler is not firing. Not stated
Electricity usage when firing (W) The amount of electricity used when the boiler is firing. Not stated
Hot water performance
Hot water flow (l/min) @ 30 degrees The flow rate is given according to a certain temperature achieved, assuming that the boiler increases the temperature of the water by 30, 35 or 40 degrees. The more the water temperature is increased the lower the flow rate. It is not applicable to heat-only or system boilers which store hot water in a separate cylinder. Not stated
Hot water flow (l/min) @ 35 degrees The flow rate is given according to a certain temperature achieved, assuming that the boiler increases the temperature of the water by 30, 35 or 40 degrees. The more the water temperature is increased the lower the flow rate. It is not applicable to heat-only or system boilers which store hot water in a separate cylinder. 14
Hot water flow (l/min) @ 40 degrees The flow rate is given according to a certain temperature achieved, assuming that the boiler increases the temperature of the water by 30, 35 or 40 degrees. The more the water temperature is increased the lower the flow rate. It is not applicable to heat-only or system boilers which store hot water in a separate cylinder. Not stated
Hot water heating efficiency (%) Measured by an independent laboratory, this is the measured energy efficiency of the boiler when it produces hot water; it is calculated to an industry standard called SAP 2009. 62.6
User controls
Concealed user controls Are the user controls hidden behind a panel. Yes
On/Off switch Yes
Timer Optional
Heating temperature control Lets you set the temperature of water in the central heating. Yes
Hot water temperature control Lets you set the temperature of the hot water supplied to the taps. Yes
Reset control Allows you to restart the boiler after problems are encountered. Yes
System pressure gauge Indicates the water pressure in the central heating system. Yes
Status display lights
Mains on Indicates that the boiler is switched on. Yes
Burner on Indicates that the boiler is heating. Yes
Central Heating indicator Illuminates when the boiler is in central heating mode. No
Domestic hot water heater Illuminates when the boiler is in domestic hot water mode. No
Boiler output temperature The temperature that the boiler is set to heat to. Yes
Boiler lockout indicator No
Fault codes feedback Yes
Manufacturer contact details
Manufacturer phone number 01905 754624
Manufacturer website www.worcester-bosch.co.uk

Worcester Greenstar 34Cdi Classic

  • Type: Gas or LPG
  • Which? score: Subscribe
Typical price
£880.00
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