I’ve got a Worcester R30 HE combi and the fault EA code is intermittent. What do I need to be looking at?

Question from John Bright, via email:
I’ve got a Worcester R30 HE combi and the fault EA code is intermittent. I’ve checked the negative pressures – all are ok. The condensate is ok, the ratios are ok and the gas inlet pressure is ok. I’ve renewed the electros and the CO2 reading is ok. What do I need to be looking at next?

Response from Martyn Bridges, director of marketing and technical support at Worcester, Bosch Group:
The EA code indicates a failed ignition attempt. Unfortunately in this instance the fault is intermittent which makes it significantly harder to diagnose, as there is no clear indication of a component failure or a setting parameter not being met.

How frequently does it occur? Is it daily or weekly? And does it occur first thing in the morning or randomly throughout the day?

Without the answers to the above, I would suggest the following is considered:

• Check the CO2 reading by inserting the analyser probe into the air inlet and ensure the reading is 20.6 – 20.9%. Any lower would indicate a flue seal problem or recirculation problem

• Clean the heat exchanger

• Change the electrode HT leads

If this doesn’t rectify the problem, call Worcester’s technical helpline from the site on 0844 892 3366.