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Vaillant Checked against MI

Vaillant ecoTEC plus open vent (415, 418, 428, 438)

Open vent heat only, natural gas and LPG

Combustion figures

FigureNatural gas (G20)LPG (G31)
CO₂ at high rate
More infoHide infoFrom Table 9.1 (the same figures are printed as Table 6.1). Section 9.1: in full load mode, wait at least 5 minutes, then measure at the combustion products test point on the flue (fig 9.1). Set the case off figure with the front and inner cover removed. The technical data table (section 2.1) gives the natural gas case on figures as Burner % CO₂ (Case on), matching Table 9.1.
415, 418, 428
Case off 9.1% +0.2/−0.5, case on 9.3% +0.2/−0.5
438
Case off 8.8% +0.2/−0.5, case on 9.0% +0.2/−0.5
415
Case off 10.1% +0.5/−0.5, case on 10.3% +0.5/−0.5
418
Case off 10.1% +0.0/−1.0, case on 10.3% +0.0/−1.0
428
Case off 10.5% +0.3/−0.8, case on 10.7% +0.3/−0.8
438
Case off 9.8% +0.2/−0.8, case on 10.0% +0.2/−0.8
CO₂ at low rate
More infoHide infoLPG: the conversion procedure (section 6) checks min rate (test program P.2) against the case off figure in Table 9.1, the same figure as at max rate. It gives no case on figure for min rate. Natural gas: the MI gives no min rate figure, as section 9.1 checks natural gas in full load mode only.
Not given in MI
415
Case off 10.1% +0.5/−0.5
418
Case off 10.1% +0.0/−1.0
428
Case off 10.5% +0.3/−0.8
438
Case off 9.8% +0.2/−0.8
Maximum CO
More infoHide infoTable 8.1 (steps 3 and 13) says to measure CO and CO₂ and compare them with Table 9.1, but Table 9.1 gives CO₂ only.
Not given in MINot given in MI
CO/CO₂ ratio
Not given in MINot given in MI
O₂
Not given in MINot given in MI
Working inlet pressure
More infoHide infoCheck at the gas valve test point with the boiler at full rate, at least 10 minutes after the burner has lit (sections 5.1.1 and 5.1.5). Section 4.3.3 says size the gas pipework so 20 mbar is available at the boiler inlet at full flow rate (it doesn’t name the gas). The technical data table (section 2.1) gives 20 mbar as the inlet gas working pressure required for natural gas, and section 10.1 says check 20 mbar is available at the gas valve. LPG: section 5.1.1 says don’t proceed if it’s lower than 34 mbar. Section 6 prints the gas supply pressure is = 34mbar, so a symbol may have been lost in print. No LPG upper limit or appliance inlet figure is given.
Gas valve test point
17–25 mbar
Gas valve test point
not lower than 34 mbar
Gas rate at maximum
More infoHide infoTable 5.1: nominal figure with the +5% and −5% limits. Check at least 10 minutes after the burner has lit (section 5.1.5). The MI contradicts itself for two natural gas sizes: the technical data table (section 2.1) gives the maximum gas rate as 1.61 m³/h for the 415 and 3.02 m³/h for the 428, against 1.62 and 3.03 in Table 5.1. The 418 (2.0) and 438 (4.06) agree.
415
1.62 m³/h (+5% 1.70, −5% 1.54)
418
2.00 m³/h (+5% 2.10, −5% 1.90)
428
3.03 m³/h (+5% 3.18, −5% 2.88)
438
4.06 m³/h (+5% 4.26, −5% 3.86)
415
1.19 kg/h (+5% 1.25, −5% 1.13)
418
1.47 kg/h (+5% 1.54, −5% 1.40)
428
2.22 kg/h (+5% 2.33, −5% 2.11)
438
2.98 kg/h (+5% 3.13, −5% 2.83)

From 0020020828_02 GB/08/2006

Enter service mode for high and low rate

High rate

Steps not added yet. Follow the MI.

Low rate

Steps not added yet. Follow the MI.
Ending the test: follow the MI.

Models and GC numbers

ModelGC numberGas
ecoTEC plus 41541-044-53NG
ecoTEC plus 41841-044-54NG
ecoTEC plus 42841-044-55NG
ecoTEC plus 43841-044-57NG

Source: Vaillant ecoTEC plus instructions for installation and servicing, wall hung open vent condensing boiler, 0020020828_02 GB/08/2006.

Sections: 1.9 Gas council numbers; 2.1 Technical data; 4.3.3 Gas connection; 5.1.1 Gas supply; 5.1.5 Testing gas (Table 5.1); 6 Natural gas to LPG conversion (Table 6.1); 8.1.4 General and Table 8.1 Inspection and maintenance steps; 9.1 Check CO2 content (Table 9.1); 10.1 Logical fault finding procedure; 10.2 Test programs.

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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.