Service mode › Atag
Atag boiler service mode
How to put an Atag boiler into service mode, so it holds maximum or minimum rate while you take combustion readings. 41 models from 10 Atag installation and servicing manuals, each step with the page it came from.
Grouped by manual: one manual usually covers a range of outputs. The CO₂ figures are the manual's own. Set and check them with a calibrated analyser, never by eye.
A200SOV Open vent heat only boiler
Covers: Sov.
GC 41-310-15
Accessing Parameter Settings (Service Mode)
- Press the OK key for 3 seconds. Display shows 'P6 81'.
- Press the OK key for 3 seconds again. Display shows 'on' followed by 'P5 18'.
- Use Scroll keys to browse parameters.
- Press OK to select/change a parameter.
- Adjust value using + or - keys.
- Press OK to confirm new setting.
- Press ESC to exit to standard display.
From manual 8G.51.70.02/08.11, page 24.
Force Maximum Rate (for O2 Checking)
- Set external controls to call for heat.
- Ensure boiler is operational and able to dissipate heat.
- Press both + keys for 6 seconds.
- The display shows the supply water temperature (blinking) and the boiler switches to maximum heating capacity.
- To terminate, press the ESC key (- key).
From manual 8G.51.70.02/08.11, page 27.
| Gas | CO₂ max rate | CO₂ min rate | CO max |
|---|---|---|---|
| Natural gas | 9% | – | – |
CO₂ and CO from manual 8G.51.70.02/08.11, page 31. Check against the data badge.
The boiler requires no adjustment of the burner pressure and quantity, because it is self-regulative and has been set in the factory and should not be reset. Only in case of a failure or when replacing the gas block, venturi and/or fan, the O2 percentage should be checked. (page 23)
ATAG A-Series
Covers: A200S, A320S, A325C, A325ECX
GC 41-310-14, 41-310-17, 47-310-17, 47-310-18
Force maximum heating capacity for O2 / combustion check
- Set the external controls to call for heat.
- Make sure the boiler is operational and can get rid of the heat it produces.
- Calibrate the O2 gauge.
- Place the lance of the O2 gauge into the flue gas test point.
- Press both + keys for 6 seconds.
- The display shows the supply water temperature (blinking); the boiler will immediately switch to the maximum heating capacity.
From manual 8G.51.59.05/08.11, page 33.
Entering Parameter Menu (Service settings)
- Press the OK key for 3 seconds. The display shows 'P6' alternated with '81'.
- Press the OK key for 3 seconds again. The display shows 'on' shortly followed by 'P5 18'.
- Use the Scroll keys to browse through the parameters, use OK to select/confirm, and use + or - to adjust values.
From manual 8G.51.59.05/08.11, page 29.
The boiler requires no adjustment of the burner pressure and quantity, because it is self-regulatory and has been set in the factory and should not be reset. (page 28)
ATAG E-Series
Covers: E Range, E22c
GC 41-310-12, 41-310-13, 47-310-13, 47-310-14
Entering Service Mode / Installer Level
- Press the Mode-key for 5 seconds until the display shows COdE followed by an arbitrary number.
- Press the + or - key until the code C123 is shown.
- Press the STORE-key to confirm the code (code blinks 1x).
- You now have access to the installer level chapters (PARA, INFO, SERV, ERRO).
- Press briefly the MODE-key to select the SERV chapter.
- Press once or more briefly on the STEP-key to select the required service parameter (1 = burner function / zero pressure check, 2 = fan adjustment with burner off, 3 = pump adjustable with burner on).
- Alter the value using the + or - key and confirm with the STORE-key.
From manual 8G.51.60.00/03.07, page 25.
Forcing Maximum and Minimum Rate (CO2 / Fan Check)
- Enter installer level using code C123 via the Mode-key.
- Press the MODE-key until SERV is shown on the display.
- Press the STEP-key once until 1 is shown (alternately 1 and OFF will be shown) for burner operation, or twice until 2 is shown for fan adjustment with burner off.
- Press the + key until the maximum value is achieved to run the boiler on full load (fan at maximum revolutions).
- Press the - key until the minimum value is achieved for minimum burner rate / fan speed.
- To end the procedure, press the - key until OFF is shown (keep key pressed) or press the Reset key.
From manual 8G.51.60.00/03.07, page 28.
The boiler settings, such as burner pressure and adjustment of the air quantity are unnecessary, due to the fact that the boiler operates with a so-called zero pressure control. This means the correct gas quantity is controlled by the suction operation of the fan. The fine adjustment which is carried out at the factory is one off, which means that adjusting of these values is unnecessary. Only when replacing the gas valve, venturi and/or the fan, does the zero pressure and the incorrect CO2 adjustment have to be checked and, if necessary, adjusted to the correct value. (page 28)
ATAG iC-Range (manual 8G.51.80.00 / 03.15)
Covers: iC 24 47-310-19 iC 24 LPG, iC 36 47-310-23 iC 36 LPG, iC 40 47-310-25 iC 40 LPG, iC Economiser 27, iC Economiser 39, iC28, iC36, iC40
GC 47-310-20, 47-310-21, 47-310-22, 47-310-23, 47-310-24, 47-310-25, 47-310-26, 47-310-27, 47-310-28, 47-310-31, 47-310-32
Enter commissioning / maximum rate mode (Checking CO2)
- Set the external controls to call for heat.
- Make sure the boiler is operational and can get rid of the heat it produces.
- Calibrate the flue gas analyser.
- Place the lance of the flue gas analyser into the flue gas test point.
- Press both + buttons for 6 seconds.
- When the flame symbol appears in the display press both + buttons again for 6 seconds.
- The display shows the supply water temperature and the boiler will switch to maximum power of the heating capacity.
- Press 1x the eco-button; the display shows the heating capacity percentage.
From manual 8G.51.80.00 / 03.15, page 41.
Force minimum rate (Low load CO2 check)
- Press on the - button until the minimum value (0%) has been reached (low load).
From manual 8G.51.80.00 / 03.15, page 42.
Exit service / commissioning mode
- Press the ESC button. The device switches off and the display shows for 2 seconds code 180 or 181.
From manual 8G.51.80.00 / 03.15, page 42.
| Model | Gas | CO₂ max rate | CO₂ min rate | CO max |
|---|---|---|---|---|
| iC 24 47-310-19 iC 24 LPG, iC 36 47-310-23 iC 36 LPG, iC 40 47-310-25 iC 40 LPG, iC Economiser 27, iC36, iC40 | Natural gas | 9.0% (-0.4 / +0.6) | – | – |
| iC 24 47-310-19 iC 24 LPG, iC 36 47-310-23 iC 36 LPG, iC 40 47-310-25 iC 40 LPG, iC Economiser 27, iC36, iC40 | LPG | 10.3% ± 0.6% | – | – |
| iC Economiser 39, iC28 | Natural gas | 9.0% (-0.4 / +0.6) | 9.0% | – |
| iC Economiser 39, iC28 | LPG | 10.3% ± ( 0.6%) | 10.3% | – |
CO₂ and CO from manual 8G.51.80.00 / 03.15, page 31, 41. Check against the data badge.
The boiler requires no adjustment of the burner pressure and quantity, because it is self-regulatory and has been set in the factory and should not be reset. (page 36)
ATAG iC-Range (manual 8G.51.84.01 / 03.19)
Covers: i24C, i28C, i40C, iC Economiser 27 Plus, iC Economiser 35 Plus, iC Economiser 39 Plus
GC 47-310-36, 47-310-37, 47-310-39, 47-310-40, 47-310-41, 47-310-42
Enter Service Mode (Chimney Sweep Function / High/Low Fire & CO2)
- Press the chimney sweep button on the control panel for 5 seconds.
- Turn the selector wheel to reach 100% for full load (high fire) or 0% for low load.
- Press OK.
From manual 8G.51.84.01 / 03.19, page 55.
Exit Service Mode
- Press the back button for 5 seconds to exit chimney sweep mode.
From manual 8G.51.84.01 / 03.19, page 56.
| Gas | CO₂ max rate | CO₂ min rate | CO max |
|---|---|---|---|
| Natural gas | 9.6% | 8.6% | 350 ppm |
| LPG | 11.0% | 9.9% | – |
CO₂ and CO from manual 8G.51.84.01 / 03.19, page 55. Check against the data badge.
The air gas ratio valve is factory set and must not be adjusted during commissioning unless this action is recommended following contact with the manufacturer. (page 58)
ATAG iR-Range
Covers: i15R, i18R, i24R, i32R, i40R
GC 41-310-49, 41-310-50, 41-310-51, 41-310-52, 41-310-53
Enter Service Mode (Chimney Sweep Function)
- Press the chimney sweep button for 5 seconds.
- Turn the selector wheel until you reach 100% for full load or 0% for low load.
- Press OK.
From manual 8G.51.85.01 / 03.19, page 46.
Exit Service Mode
- Press the back button for 5 seconds to exit chimney sweep mode.
From manual 8G.51.85.01 / 03.19, page 47.
| Model | Gas | CO₂ max rate | CO₂ min rate | CO max |
|---|---|---|---|---|
| i15R, i18R, i24R, i32R | Natural gas | 9.6% | 8.6% | 350 ppm |
| i15R, i18R, i24R, i32R | LPG | 11.0% | 9.9% | 350 ppm |
| i40R | Natural gas | 9.0% ± Minimum 8.6%, maximum 9.6% | 9.0% | 350 ppm |
| i40R | LPG | 10.3% ± Minimum 9.9%, maximum 11.0% | 10.3% | 350 ppm |
CO₂ and CO from manual 8G.51.85.01 / 03.19, page 46. Check against the data badge.
The air gas ratio valve is factory set and must not be adjusted during commissioning unless this action is recommended following contact with the manufacturer. (page 49)
ATAG iS-Range (manual 8G.51.82.03 / 01.16)
Covers: iS 12, iS 12 41-310-18 iS 12 LPG, iS15, iS18, iS24, iS40
GC 41-310-18, 41-310-19, 41-310-20, 41-310-21, 41-310-22, 41-310-23, 41-310-24, 41-310-25, 41-310-28, 41-310-29
Enter Commissioning/Service Mode for CO2 check
- Set the external controls to call for heat.
- Make sure the boiler is operational and can get rid of the heat it produces.
- Calibrate the flue gas analyser.
- Place the lance of the flue gas analyser into the flue gas test point.
- Press both + buttons for 6 seconds.
- When the flame symbol appears in the display press both + buttons again for 6 seconds.
- The display shows the supply water temperature and the boiler switches to maximum power of the heating capacity.
- Press 1x the eco-button; the display shows the heating capacity percentage.
- To check low load, press on the - button until the minimum value (0%) has been reached.
From manual 8G.51.82.03 / 01.16, page 44.
Exit Service Mode
- Press the ESC button (ESC / - button).
- The device switches off.
- The display shows for 2 seconds code 180 or 181.
From manual 8G.51.82.03 / 01.16, page 45.
| Gas | CO₂ max rate | CO₂ min rate | CO max |
|---|---|---|---|
| LPG | 10.3% ± ( 0.6%) | – | – |
CO₂ and CO from manual 8G.51.82.03 / 01.16, page 44. Check against the data badge.
The air gas ratio valve is factory set and must not be adjusted during commissioning unless this action is recommended following contact with the manufacturer. (page 46)
ATAG iS-Range (manual 8G.51.86.01 / 03.19)
Covers: i15S, i18S, i24S, i40S
GC 41-310-44, 41-310-45, 41-310-46, 41-310-48
Enter Service Mode (Chimney Sweep Mode) for CO2 Check
- Press the chimney sweep button for 5 seconds.
- Turn the selector wheel until you reach 100% for full load, or 0% for low load.
- Press OK to activate the selected rate.
From manual 8G.51.86.01 / 03.19, page 56.
Exit Service Mode
- Press the back button for 5 seconds to exit chimney sweep mode.
From manual 8G.51.86.01 / 03.19, page 57.
| Model | Gas | CO₂ max rate | CO₂ min rate | CO max |
|---|---|---|---|---|
| i15S, i24S | Natural gas | 9.0% | – | 350 ppm |
| i15S, i24S | LPG | 10.3% | – | – |
| i18S, i40S | Natural gas | 9.6% | 8.6% | 350 ppm |
| i18S, i40S | LPG | 11.0% | 9.9% | 350 ppm |
CO₂ and CO from manual 8G.51.86.01 / 03.19, page 8, 56. Check against the data badge.
The air gas ratio valve is factory set and must not be adjusted during commissioning unless this action is recommended following contact with the manufacturer. (page 59)
ATAG Premier E-SHR series
Covers: Premier
GC 47-310-01, 47-310-02
Force Max/Min Rate for CO2 Check
- In Service Mode Step 1, adjust to maximum load by means of the '+' key.
- Identify minimum load by pressing the '-' key until minimum is reached.
- Press '-' key again while at minimum to turn selection 'Off'.
From manual 8G.51.18.01/07.04, page 22.
| Gas | CO₂ max rate | CO₂ min rate | CO max |
|---|---|---|---|
| Natural gas | 9% | – | – |
| LPG | 10.5% | – | – |
CO₂ and CO from manual 8G.51.18.01/07.04, page 24. Check against the data badge.
The boiler does not require adjustment of the burner pressure and air quantity because it is self adjusting and is factory set at the correct value. The fine adjustment which is carried out at the factory is once-only, which means that adjusting of these values is unnecessary. (page 17)
ATAG Q-Serie
Covers: Q 25S, Q 30CR, Q25SC, Q38SC
GC 41-310-08, 41-310-09, 41-310-10, 41-310-11, 47-310-10, 47-310-11, 47-310-12
Entering Service Mode and Adjustments
- Press the Mode-key for 5 seconds until the display shows COdE followed by an arbitrary number.
- Press by means of the + or the - key until the code C123 is shown.
- Press the STORE-key to confirm the code (code blinks 1 x) to access installer level.
- Press briefly the MODE-key to select the SERV chapter.
- Press briefly on the STEP-key to select service parameters (1 for zero pressure/CO2 test, 2 for fan adjustment, 3 for pump adjustment, 4 for showroom position).
- Press the - key until OFF is shown (keep key pressed) or press Reset key to end the procedure.
From manual 8G.51.40.00/03.06, page 30.
Forcing Maximum and Minimum Rate (CO2 / Zero Pressure Check)
- Enter service mode with code C123.
- Navigate to SERV chapter.
- Press STEP-key until 1 is shown (alternately 1 and OFF) for zero pressure / CO2 check, or 2 for maximum fan speed.
- Press the + key until the maximum value is achieved to run on full load.
- Press the - key until the minimum value is achieved for minimum rate.
- Press the - key until OFF is shown (keep key pressed) or press the Reset key to end the procedure.
From manual 8G.51.40.00/03.06, page 30.
The fine adjustment which is carried out at the factory is once-only, which means that adjusting of these values is unnecessary. Only in case of replacing of the gas valve, venturi and/or fan the zero pressure and the incorrect CO2 adjustment has to be checked and, if necessary, adjusted at the right value. (page 30)
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Common questions
Is service mode the same as chimney sweep mode?
Yes, in practice. Makers use different names for the same function: service mode, chimney sweep mode, test mode, calibration mode, check programme. Each one holds the burner at a fixed rate, usually maximum then minimum, so you can take a stable combustion reading.
Can I adjust the gas valve while it's in service mode?
Only where the manual gives an adjustment procedure, and only with an analyser in the flue. Many current boilers are set at the factory and the manual says not to touch the gas valve. Where a manual says that, it is shown with the procedure above.
Other makers
AlphaAristonBaxiBiasiChaffoteauxFerroliGlow-wormHalsteadHeatlineIdealIntergasJohnson StarleyKestonMainPottertonRemehaSimeVaillantViessmannVokeraWorcester Bosch
Service mode and combustion checks are work for a competent, Gas Safe registered engineer. These procedures are taken from the manufacturers' manuals and inform your judgement; they don't replace it. Always work to the manual for the exact appliance, its data badge and the current standards.