Combined or separate?

Ravenheat CSI Primary 85T runs a two-electrode kit — one spark, one sense. Fit both together to avoid a second call-back.

How do I test ionisation current?

In service mode read the µA value on Ravenheat CSI Primary 85T. Below 4 µA at steady state means clean or replace.

Only if the Ravenheat CSI Primary 85T is in warranty — Ravenheat require log of any part swap for labour claims.

Renew the ignition and flame-sense electrodes on Ravenheat CSI Primary 85T when you get F27 / EA / L2 flame-detection faults after a clean burn.

Both electrodes on Ravenheat CSI Primary 85T use ceramic insulators — never re-use if chipped.

Set the spark gap to 3.5–4.0 mm and the ionisation gap so the tip sits 4–5 mm above the burner surface.

Refill the Ravenheat CSI Primary 85T to 1.2 bar cold. Bleed high-point radiators and the internal AAV.

Run a full flue-gas analysis after 15 minutes. Log the reading against the OEM commissioning envelope in the Benchmark book.

Combined or separate?: Ravenheat CSI Primary 85T runs a two-electrode kit — one spark, one sense. Fit both together to avoid a second call-back.
How do I test ionisation current?: In service mode read the µA value on Ravenheat CSI Primary 85T. Below 4 µA at steady state means clean or replace.
Do I need to notify the manufacturer?: Only if the Ravenheat CSI Primary 85T is in warranty — Ravenheat require log of any part swap for labour claims.

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