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Service mode › Heatline

Heatline boiler service mode

How to put a Heatline boiler into service mode, so it holds maximum or minimum rate while you take combustion readings. 14 models from 8 Heatline 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.

CaprizPlus

Covers: CaprizPlus 24, CaprizPlus 28

GC 47-157-19, 47-157-20

Activate Test Modes (P.01 - P.07)

  1. Switch off the appliance using the on/off button.
  2. While keeping the button pressed for more than 5 seconds, press the on/off button.
  3. The screen displays the first test mode 'P1' and 'Off'.
  4. Press button or to choose the test mode that you wish to launch.
  5. For test mode 'P1': Press button to display the burner forcing setting. The screen displays 'P1' and 'Lo'.
  6. Press on button or to modify the value of the setting from 'Lo' (0%) to 'Hi' (100%).
  7. Press on button for 1 second to exit the submenu or for more than 7 seconds to access the configuration menu.
  8. For test modes 'P2' to 'P7': Press to launch the test mode. The screen displays 'PX' and 'On'.
  9. The test mode will automatically stop after 15 minutes.
  10. When you have finished, press the reset button to exit the test modes.

From manual 0020112883-01, page 27.

Access Configuration Menu and Parameters (Installer Level)

  1. Press for more than 7 seconds on the button (mode) to access the configuration menu. The screen displays "0".
  2. Press 4 times on the button (-). The screen displays "96". This is the installer's password.
  3. Press on (mode) to validate. The screen displays a flashing and alternating "d." and "00".

From manual 0020112883-01, page 25.

GasCO₂ max rateCO₂ min rateCO max
Natural gas9.2% ± 0.3%8.9% ± 0.3%–
LPG10.3% ± 0.3%9.8% ± 0.3%–

CO₂ and CO from manual 0020112883-01, page 7. Check against the data badge.

The combustion for this appliance has been checked, adjusted and preset at the factory for operation on natural gas (G20) as defined on the appliance data label. No measurement of the combustion is necessary. (page 22)

Heat Line S24/S30 Compact Wall Mounted Combination Boiler Installation, Servicing and

Covers: S30 Compact

GC 47-157-03

Entering Service Mode / Forcing Rate and Onboard Adjustments

  1. Potentiometers can be reached by removing the cover on the rear of the control panel.
  2. To reach the dip switches, the control panel must be opened.
  3. Adjust potentiometer '3' to set the maximum central heating output with the boiler burner firing and a pressure gauge attached to the boiler's gas valve outlet test point.
  4. The ignition rate of the valve can be forced from minimum to maximum rate by setting potentiometer 4 (gas valve ignition capacity) clockwise.

From manual 0302093, page 28.

Gas Type Jumper, Dip Switch 1, Dip Switch 4 and Dip Switch 5 are factory set and must not be adjusted. (page 29)

Heat Line™ C24/C28 Condensing Combination Boilers

Covers: C24

GC 47-157-06, 47-157-07

Service Mode / Rate Adjustment

  1. Attach pressure gauge to the boiler gas valve outlet test point.
  2. With burner firing, adjust potentiometer '3' until required burner pressure is obtained.
  3. Gas valve ignition capacity can be forced from minimum to maximum rate by setting potentiometer '4' clockwise.

From manual 3003200910-R2, page 28.

Gas Valve Re-calibration (Minimum Setting)

  1. Remove one lead from the modulating gas valve coil.
  2. Turn function switch to 'Winter' position.
  3. Turn CH temperature control to maximum.
  4. Turn inner part by plain screwdriver clockwise to increase, anticlockwise to decrease.

From manual 3003200910-R2, page 41.

Gas Valve Re-calibration (Maximum Setting)

  1. Push the ball inside the modulating gas valve coil using a sharp pointed tool.
  2. Turn outer part by a 10 size spanner clockwise to increase, anticlockwise to decrease.

From manual 3003200910-R2, page 41.

The maximum and minimum heat output for domestic hot water is pre-set on the gas valve. It is not necessary to make further adjustments. (page 29)

HEATLINE CAPRIZ 25S / CAPRIZ 28S Condensing System Boilers Installation, Servicing &

Covers: Capriz 25S

GC 41-157-10

Forcing Ignition Rate

  1. The graduated opening of nimble gas valve for ignition rate is governed by the 1st potentiometer P4 control.
  2. The ignition rate of the valve can be forced from minimum to maximum rate by setting the potentiometer clockwise.

From the installation and servicing manual, page 21.

Gas Type Jumper, Dip Switch 1, Dip Switch 4 and Dip Switch 5 are factory set and must not be adjusted. (page )

Heatline Sargon 24 / 30 / 35 Pre-mix Condensing Combination Boiler Installation, Servicing &

Covers: Sargon 24, Sargon 30, Sargon 35

GC 47-157-15, 47-157-16, 47-157-17

Entering Service Mode

  1. Turn the thermostat control knobs 2 & 3 (Figure 18) to minimum.
  2. Turn selector control knob (4 Figure 18) from OFF to On (Heating Mode) three times each within a two second interval.
  3. A wrench symbol will be displayed in the LCD window and the boiler will ignite at minimum rate.
  4. The boiler is now in service mode and will stay there for 15mins.
  5. To obtain maximum rate simply turn the C/H control knob to max.

From the installation and servicing manual, page 28.

ModelGasCO₂ max rateCO₂ min rateCO max
Sargon 30Natural gas10.0% (+0.1)9.5% (+0.1)–
Sargon 30LPG11.0% (+0.1)10.9% (+0.1)–
Sargon 35Natural gas10.0% (+0.1)9.9% (+0.1)–
Sargon 35LPG10.8% (+0.1)10.8% (+0.1)–
Sargon 24Natural gas9.1%8.5%–
Sargon 24LPG10.7%10.6%–

CO₂ and CO from the installation and servicing manual, page 7, 35. Check against the data badge.

Heatline Solaris 24PC/30PC Pre-mix Condensing Combination Boiler

Covers: Solaris 24PC, Solaris 30PC

GC 47-157-04, 47-157-05

Enter Service Mode

  1. Turn selector control knob (3 figure 17) 3 times between C/H setting and the off position (no more than 2 seconds between each turn)
  2. The boiler is now in service mode and will stay there for 15mins

From the installation and servicing manual, page 21.

Force Max and Min Rate

  1. Turn both C/H & DHW controls to max to set the boiler to max output and will not modulate
  2. Turn both the controls to min to set the boiler on min without modulation for setting up the default parameters

From the installation and servicing manual, page 21.

This boiler has been factory set and does not require any adjustments to the gas valve or fan speed. (page 9)

Heatline Vizo 24 / Vizo 28 Installation, Servicing &

Covers: Vizo 24, Vizo 28

GC 47-157-08, 47-157-09

Entering Service Mode & Adjusting Parameters

  1. To access potentiometers, remove the cover on the rear of the control panel.
  2. To reach the dip switches, open the control panel.
  3. Force minimum to maximum rate for setting modulating gas rate parameters by turning the 1st potentiometer P7 or forcing ignition rate using potentiometer P4.

From the installation and servicing manual, page 21.

This boiler has been factory set and does not require any adjustments to the gas valve or fan speed. (page )

Monza

Covers: Monza 24, Monza 28

GC 47-157-21, 47-157-22

Enter Test Modes (P1 to P7)

  1. Press the on/off button to switch off the appliance.
  2. While keeping the mode button pressed for more than 5 seconds, press the on/off button. The screen displays the first test mode "P1" and "Off".
  3. Press the + button or the - button to choose the test mode that you wish to launch.
  4. Test mode "P1": Press the mode button to display the burner forcing setting. The screen displays "P1" and "Lo".
  5. Press the + button or the - button to modify the value of the setting from "Lo" (0%) to "Hi" (100%).
  6. Press the mode button for 1 second to exit the submenu or for more than 7 seconds to access the configuration menu.
  7. Test mode "P2" to "P7": Press the mode button to launch the test mode. The screen displays "PX" and "On". The test mode will automatically stop after 15 minutes.
  8. When you have finished, press the reset button to exit the test modes.

From manual 0020112884-01, page 27.

Force Max & Min Rate (Test mode P.01 / P1)

  1. Press the on/off button to switch off the appliance.
  2. While keeping the button mode pressed for more than 5 seconds, press the on/off button. The screen displays the first test mode "P1" and "Off".
  3. Press button + or - to choose the test mode that you wish to launch.
  4. Test mode "P1" :
  5. Press button mode to display the burner forcing setting. The screen displays "P1" and "Lo".
  6. Press on button + or - to modify the value of the setting from "Lo" (0%) to "Hi" (100%).
  7. Press on button mode for 1 second to exit the submenu or for more than 7 seconds to access the configuration menu.

From manual 0020112884-01, page 27.

GasCO₂ max rateCO₂ min rateCO max
Natural gas9.2% ± 0.3%8.9% ± 0.3%–
LPG10.3% ± 0.3%9.8% ± 0.3%–

CO₂ and CO from manual 0020112884-01, page 7. Check against the data badge.

The combustion for this appliance has been checked, adjusted and preset at the factory for operation on natural gas (G20) as defined on the appliance data label. No measurement of the combustion is necessary. Should the appliance require to be converted to LPG gas ensure you follow the gas conversion section before lighting the boiler. (page 22)

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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

AlphaAristonAtagBaxiBiasiChaffoteauxFerroliGlow-wormHalsteadIdealIntergasJohnson 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.