Replacing Turbulator Powermax 155

There are actually eight turbulators (spiral metal rods - see here: www.directheatingsupplies.co.uk/powermax-turbulator-p626) inside a Powermax 155, which are supposed to improve the flow of heat from the burner throughout the water cylinder (although they're not in direct contact with the water). Recommended exchange periodicity is every seven years, I understand. They're not expensive (around £20 each), but it's not an easy job to fit them - you really need someone who's used to servicing Powermax boilers. Not replacing them won't stop the boiler working or create a safety hazard, but will make it less efficient.

As to whether it should have been noticed before, you'll have to take that up with those involved - but again, someone unfamiliar with Powermax boilers probably wouldn't realise it needed doing.