Ideal Logic: 2016 Propane Logic + Heat that won’t ignite,

1. 1. Verify gas supply to other appliances.

   Why: Confirming gas supply to other appliances rules out a wider gas network issue or a problem with the property's gas meter or emergency control valve.

   How: Turn on a gas hob or other gas appliance in the property to ensure it is functioning correctly. Check the gas meter's emergency control valve is open (lever parallel to the pipe).

2. 2. Check gas valve coil resistance.

   Why: An incorrect resistance reading on the gas valve coil can indicate an internal fault with the valve, preventing it from opening correctly even with the correct voltage supply.

   How: Isolate the electrical supply to the boiler. Disconnect the gas valve harness from the PCB (connection X3 for the gas valve). Measure the resistance across the two outer pins of the gas valve connection on the PCB. For a 24V DC gas valve (indicated by a blue tab), expect a reading between 100 and 200 ohms, or around 114.5 ohms.

3. 3. Inspect the condensate trap and pipework for blockages.

   Why: A blocked condensate trap or pipe can prevent the boiler from igniting as a safety measure, as it can interfere with the combustion process.

   How: Visually inspect the condensate trap and pipework for any signs of blockages, kinks, or freezing, especially if the external pipe is exposed to cold weather. Clear any obstructions found.

4. 4. Test the flame rectification circuit (microamps).

   Why: Even with a spark and gas, if the flame sensor doesn't detect a flame, the boiler will shut down the gas supply as a safety precaution, leading to an ignition lockout.

   How: Set your multimeter to the microamp (µA) DC setting. Disconnect the flame sensor wire and connect your multimeter in series with the flame sensor and its wire. Initiate a call for heat and observe the microamp reading once the boiler attempts to ignite. Expect a reading typically between 2-7 µA DC when the flame is established.

5. 5. Verify flue and air intake are clear.

   Why: A blocked flue or air intake can lead to an ignition lockout by preventing proper combustion and safe expulsion of flue gases.

   How: Visually inspect the flue terminal outside for any obstructions (e.g., bird's nest, debris). Check the internal flue components and air intake for blockages.

6. 6. Check for correct polarity and earth continuity.

   Why: Incorrect electrical polarity or a poor earth connection can interfere with the boiler's electronic controls and flame rectification circuit, preventing ignition.

   How: Using a suitable multimeter, verify correct live, neutral, and earth connections and continuity at the boiler's electrical supply and within the boiler's wiring harness. Ensure a proper 120V dedicated ground.

7. 7. Consider a faulty Printed Circuit Board (PCB).

   Why: If all other components test correctly, a faulty PCB may be failing to control the ignition sequence or process the flame signal correctly, leading to an ignition lockout.

   How: If all previous checks yield no fault, and considering the spark generator and electrode are new, the PCB could be faulty. This would require further diagnostic steps as per the manufacturer's instructions, potentially leading to PCB replacement.

More Ideal fault codes

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Sources

The AI cross-checked the following manufacturer and trade sources while producing this checklist.

• boilers2go.co.uk
• youtube.com
• youtube.com
• youtube.com
• urbanplumbers.co.uk
• idealheating.com
• 0800homefix.com
• berksinsulation.com
• hvacknowitall.com
• hvacbasics.com
• hvactrainingsolutions.net
• serviceteam.co.uk
• maintracts.co.uk
• ideal-partnership.co.uk
• davidosborneheating.com
• superwarm.co.uk