Alpha Alpha Evoke combi (Evoke 28, 33)
Combi, natural gas and LPG
Combustion figures
| Figure | Natural gas (G20) | LPG (G31) |
|---|---|---|
CO₂ at high rate More infoHide infoMI figure for CO₂ at maximum DHW output, checked in chimney sweep mode at 99% (max DHW output) with the case fitted. The technical data also gives CO₂ at maximum CH output (NG: Evoke 28 9.7%, Evoke 33 9.5%; LPG: Evoke 28 11.4%, Evoke 33 11.2%, no tolerance given), but MI 6.6 says CO₂ testing at the 80–90% max CH output setting is not required. MI 6.6 refers to Section 2.1 for the tolerance, but Section 2 is safety symbols: the tolerances are in Sections 3.1 and 3.2. |
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CO₂ at low rate More infoHide infoCO₂ at minimum output, chimney sweep mode at 0% (low fire), case fitted. |
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Maximum CO More infoHide infoRate not stated in MI. LPG: the MI’s LPG table (Section 3.2) says other technical data is the same as NG data. | 450 ppm | 450 ppm |
CO/CO₂ ratio More infoHide infoMaximum CO/CO₂ ratio. If above 0.004, MI Section 7 says check for flue gas recirculation, flue restrictions and gas supply pressure and rate, then clean the burner and check the electrode. LPG: taken from the NG data, as Section 3.2 says other technical data is the same. | 0.004 | 0.004 |
O₂ | Not given in MI | Not given in MI |
Working inlet pressure More infoHide infoGiven as gas supply pressure in the technical data, with no range or tolerance. Measurement point not stated in MI. | 20 mbar | 37 mbar |
Gas rate at maximum More infoHide infoGas rate at maximum output, as given in the technical data. |
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From Part No. 1.042372 rev. ST.003782.000 (0918/D386)
Enter service mode for high and low rate
High rate
- With no heating or hot water demand, hold RESET for 8 seconds. The parasol and snowman symbols flash together.
- Press the hot water up button (top left, tap symbol with an up arrow) until it reaches maximum, 99%.
- If a Climatic controller is fitted it shows ERR>07. That’s not a fault.
Low rate
- Press the hot water down button (bottom left, tap symbol with a down arrow) until it reaches minimum, 0%.
- Press the hot water up button to go back to maximum.
Ending the test
- Turn the boiler off (hold the Off/Stand-by/Summer/Winter button for 8 seconds) to come out. It also ends by itself after 15 minutes.
Models and GC numbers
| Model | GC number | Gas |
|---|---|---|
| Evoke 28 (NG) | 47-532-71 | NG |
| Evoke 28 (LPG) | 47-532-75 | LPG |
| Evoke 33 (NG) | 47-532-72 | NG |
| Evoke 33 (LPG) | 37-532-76 | LPG |
Source: Alpha Evoke 28 and 33 Installation and Servicing Instructions, Part No. 1.042372 rev. ST.003782.000 (0918/D386).
Sections: 3.1 Technical performance data - natural gas; 3.2 Technical performance data - LPG; 6.6 Checking the combustion - chimney sweep mode; 6.11 Converting the boiler to operate on LPG; 6.12 CO2 set up procedure; 7 Routine servicing (combustion check).
Spotted something wrong? Tell us.
Check these figures against the MI for the appliance in front of you, matched by GC number and manual date. Combustion work needs a calibrated analyser and a Gas Safe registered engineer.