01782 983376
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The gas engines used in CHP plants and infrastructure environments are typically expected to operate for long periods with minimal interruption. In these settings, unplanned outages or unstable running conditions can have knock-on effects on site operations, maintenance planning, and compliance. From our experience at RM Walsh, ignition system performance is a frequent contributor to avoidable issues in otherwise well-maintained engines.
Why? Because a gas-powered engine depends entirely on consistent ignition to maintain stable combustion. When spark energy begins to drop or ignition timing becomes inconsistent, the first symptoms are often misfires, rough running, or fluctuating output. Left unaddressed, these issues increase thermal and mechanical stress on the engine, accelerating wear on its components and increasing the risk of secondary failures.
Ignition problems create secondary failures
This is worth exploring in more detail, as one of the major challenges with ignition-related faults is that they tend to trigger secondary issues elsewhere in the engine. Incomplete combustion increases thermal loading on exhaust valves and turbochargers, for example, while misfires introduce vibrations and uneven cylinder pressures. These components are usually significantly more expensive and disruptive to replace than ignition parts!
For CHP operators, this cascade of issues also affects system efficiency. Unstable combustion reduces electrical output and undermines the engine’s heat recovery process. From what we see in the field, engines that suffer repeated ignition instability often need shorter maintenance intervals and have less predictable operating costs. Addressing ignition reliability problems as soon as they are detected helps avoid these knock-on effects and keeps your maintenance planning under control.
Spark plug choice has a disproportionate impact
In CHP and infrastructure engines, industrial spark plugs play a disproportionately large role in overall engine stability. We regularly see problems caused by spark plugs that are technically compatible with an engine, but not suited to how it is actually being run. For instance, a plug that performs adequately at steady load may struggle during load changes, while another may foul during extended low-load operations. As electrode wear progresses, spark energy drops off gradually, making performance degradation difficult to detect until misfires or alarms occur.
Fuel variability complicates ignition performance
Fuel quality has a direct influence on how much margin the ignition system has available, with variations in inert content or contaminants changing how readily the air–fuel mixture ignites. What we focus on at RM Walsh is how ignition components respond to those variations over time. A spark plug that performs well under stable fuel conditions may struggle as ignition demand increases. If that response isn’t anticipated during specification, your operators may be left with a narrower window before instability appears.
By accounting for fuel behaviour when selecting your ignition components, it becomes possible to maintain more consistent combustion even as your operating conditions change. This doesn’t eliminate variability, but it does make engine behaviour more reliable and easier to manage.
Ignition as a control variable, not a consumable
From our standpoint, ignition decisions on CHP sites are most effective when they’re treated as part of operational control, not just as routine maintenance decisions. Spark plugs, leads, and coils all influence how an engine responds to load, fuel changes, and control inputs over time. When ignition components are selected with the operating context in mind, engines tend to show clearer performance trends and fewer ambiguous faults. The positive knock-on from this is the way it makes diagnostics simpler, maintenance planning more reliable, and overall availability easier to protect.
Ultimately, for CHP operators, ignition reliability isn’t about chasing maximum component life, but about keeping engine behaviour stable enough that issues are identified early and addressed on their own terms, rather than after performance has already been compromised.
Next steps
So, if you’re seeing unexplained misfires, unstable running, or recurring CHP plant downtime, it’s often worth taking a closer look at the ignition system before those symptoms escalate. Faulty spark plugs and poorly matched ignition components are common contributors to problems that appear mechanical or fuel-related on the surface. At RM Walsh, we work with CHP operators to review ignition setup in the context of how their engines are actually run; load profile, fuel behaviour, and service expectations included. A short conversation early on can prevent ignition issues from turning into wider engine problems later, so feel free to drop us a line on 01782 983592.
Seeing recurring misfires or unpredictable behaviour from a CHP engine? Our latest article breaks down how ignition system performance particularly spark plug choice affects combustion stability, efficiency, and long-term reliability in CHP and infrastructure environments. Read the full article here.
