Service mode › Johnson Starley

Johnson Starley boiler service mode

How to put a Johnson Starley boiler into service mode, so it holds maximum or minimum rate while you take combustion readings. 11 models from 10 Johnson Starley 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.

Johnson & Starley Combi Series Reno High Efficiency Combination Boilers

Covers: Reno HE

GC 41-416-02, 47-416-01, 47-416-02, 47-416-03, 47-416-04

Entering Test Mode

Press and hold the ▼ button.
Whilst holding the ▼ button, press and hold the MODE button together until the display changes.
If the display shows E H I 5, press RESET and try again.
Use the ▲ and ▼ buttons to scroll between maximum and minimum rates.
Press RESET to take the appliance out of test mode.

From manual ZZ1183-12, page 21.

Gas	CO₂ max rate	CO₂ min rate	CO max
Natural gas	9.5% (+0.5)	8.4%	–
LPG	10.2%	9.4%	–

CO₂ and CO from manual ZZ1183-12, page 4. Check against the data badge.

The gas valve is factory preset and must not be adjusted. A replacement valve must only be supplied by Johnson & Starley Ltd. (page 20)

QUANTEC COMBI ErP High Efficiency Combination Boiler

Covers: QuanTec 24C, Quantec 30C-SA

GC 47-416-12, 47-416-13

Test Mode Entry and Operation

To put the unit into test mode, press and hold K1 and K2 for 5 seconds.
Use K1 and K2 to select the required setting.
To reset, press K4 button twice.

From manual ZZ 1432-8, page 25.

Model	Gas	CO₂ max rate	CO₂ min rate	CO max
QuanTec 24C	Natural gas	9.3% ± 0.5	8.3% ± 0.5	–
Quantec 30C-SA	Natural gas	9.4% ± 0.5	8.6% ± 0.5	–

CO₂ and CO from manual ZZ 1432-8, page 8. Check against the data badge.

The combustion for this appliance has been checked, adjusted and preset at the factory for operation on the gas type defined on the appliance data plate. Do not adjust the air/gas ratio valve. (page 23)

QUANTEC HR28C ErP High Efficiency Boiler with Passive Flue Gas Heat Recovery

Covers: Quantec HR28C

GC 47-416-11

Test Mode

To put the unit into test mode, press and hold K1 & K2 for 5 seconds.
Using K1 and K2 to select the required setting.
To reset press K4 button twice.

From manual ZZ 1430-8, page 25.

Gas	CO₂ max rate	CO₂ min rate	CO max
Natural gas	9.4% ± 0.5	8.6% ± 0.5	–

CO₂ and CO from manual ZZ 1430-8, page 8. Check against the data badge.

QUANTEC HR28CP ErP High Efficiency Boiler with Passive Flue Gas Heat Recovery

Covers: Quantec HR28CP

GC 47-416-14

Enter Test Mode

To put the unit into test mode, press and hold K1 & K2 for 5 seconds.
Using K1 and K2 to select the required setting.
To reset press K4 button twice.

From manual ZZ 1585-2, page 25.

Gas	CO₂ max rate	CO₂ min rate	CO max
LPG	10.1% ± 0.5	9.2% ± 0.5	–

CO₂ and CO from manual ZZ 1585-2, page 8. Check against the data badge.

The gas input to the burner is regulated by the gas valve according to the air flow produced by the fan. It is not user-adjustable. Any interference to sealed settings on the gas valve will adversely affect operation and render our warranty void. (page 25)

QUANTEC SYSTEM ErP High Efficiency Boiler

Covers: Quantec 24S

GC 41-416-16

Test Mode Entry

To put the unit into test mode, press and hold K1 & K2 for 5 seconds.
Using K1 and K2 to select the required setting.
To reset boiler press the reset button ‘K4’ twice.

From manual ZZ 1434-7, page 24.

Gas	CO₂ max rate	CO₂ min rate	CO max
Natural gas	9.4% ± 0.5	8.6% ± 0.5	–

CO₂ and CO from manual ZZ 1434-7, page 7. Check against the data badge.

WARMCAIR C16U Condensing Air Heater

Covers: C16u

GC 42-451-23

Enter Test Mode

Press 'Summer Air Circulation' (SAC) and 'C' buttons together for more than 3 seconds until display changes.
Display shows 't100' or similar with flame symbol.
Use 'D' and 'E' buttons to toggle between maximum and minimum rates.
Press 'RESET' to exit.

From manual ZZ 1412-5, page 25.

Gas	CO₂ max rate	CO₂ min rate	CO max
Natural gas	10%	8%	–

CO₂ and CO from manual ZZ 1412-5, page 8. Check against the data badge.

The gas valve is factory preset and must not be adjusted. A replacement valve must only be supplied by Johnson & Starley Ltd. (page 16)

WarmCair C26D Condensing Air Heater

Covers: C26d

GC 42-417-98

Enter Test Mode

Ensure gas supply is on and mains power is connected.
Press Summer Air Circulation (SAC) and C buttons together for more than 3 seconds until display changes.
Display will show 't100' along with the flame symbol.
Use D and E buttons to toggle between maximum and minimum rates.
Press RESET to exit test mode (or wait 30 minutes for timeout).

From manual ZZ 1409-6, page 26.

Gas	CO₂ max rate	CO₂ min rate	CO max
Natural gas	10%	7%	–

CO₂ and CO from manual ZZ 1409-6, page 4. Check against the data badge.

The gas valve is factory preset and must not be adjusted. A replacement valve must only be supplied by Johnson & Starley Ltd. (page 17)

WarmCair Condensing Warm Air (manual ZZ 1339-6)

Covers: C10d

GC 42-416-99

Entering Test Mode

Press Summer Air Circulation (SAC) and C buttons together for more than 3 seconds.
t100 is displayed along with the flame symbol.
Use D and E buttons to scroll between maximum and minimum rates.
Press RESET to exit.

From manual ZZ 1339-6, page 26.

Entering Fan Test Mode

Press C and RESET for 3 seconds.
F and fan speed value will display.
Use A and B buttons to change value.
Press D to save as minimum.
Press E to save as maximum.
Press RESET to terminate.

From manual ZZ 1339-6, page 26.

The gas valve is factory preset and must not be adjusted. A replacement valve can only be supplied by Johnson & Starley Ltd. (page 17)

WarmCair Condensing Warm Air (manual ZZ 1408-4)

Covers: C16d

GC 42-415-19

Entering Test Mode

Press Summer Air Circulation (SAC) and C buttons together for more than 3 seconds.
Display will show t100 and a flame symbol.
Use D and E buttons to scroll between maximum and minimum rates.
Press RESET to exit.

From manual ZZ 1408-4, page 26.

Fan Test Mode

Press C and RESET for 3 seconds.
Display shows F and fan speed value.
Use A and B buttons to adjust value (range 50-100).
Save minimum rate by pressing button D.
Save maximum rate by pressing button E.
Press RESET to exit.

From manual ZZ 1408-4, page 26.

Gas	CO₂ max rate	CO₂ min rate	CO max
Natural gas	10%	7%	–

CO₂ and CO from manual ZZ 1408-4, page 4. Check against the data badge.

The gas valve is factory preset and must not be adjusted. A replacement valve must only be supplied by Johnson & Starley Ltd. (page 17)

WarmCair DW Series II

Covers: Warmcair DW

Enter Installer/Service Mode

Press and hold all 3 buttons on the control panel for 10-15 seconds to access installer mode.
Display will show Pr00.

From manual ZZ 1670, page 25.

Sweep Test (Force Max/Min Rate)

Enter installer mode.
Press and hold + & - button on control panel to access sweep test mode.
LP shows on display (min rate).
Press + button to cycle to dP (max rate).

From manual ZZ 1670, page 25.

Exit Service Mode

Press and hold the reset button to switch off the heater.

From manual ZZ 1670, page 25.

Gas	CO₂ max rate	CO₂ min rate	CO max
Natural gas	9.2% ± 0.5	8.0%	–

CO₂ and CO from manual ZZ 1670, page 8. Check against the data badge.

The gas input to the burner is regulated by the gas valve according to the air flow produced by the combustion air fan. It is not user-adjustable. Any interference to sealed settings on the gas valve will adversely affect operation and render our warranty void. (page 24)

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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

Alpha Ariston Atag Baxi Biasi Chaffoteaux Ferroli Glow-worm Halstead Heatline Ideal Intergas Keston Main Potterton Remeha Sime Vaillant Viessmann Vokera Worcester 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.