The warning comes following an incident involving a three-year-old ride-on mower which needed repair work, but was not covered because the owner had failed to register the machinery at the time of purchase.
Etesia UK general manager Les Malin said: "Warranty registration is such a vital part of our customer service – apart from the obvious peace of mind it gives the customer, it ensures a tight working relationship between them and their local Etesia dealer.
"We pay dealers for any repair work they may have to carry out should there be a fault to a machine as a direct result of manufacture, and failure to register at the time of purchase means this whole process breaks down."
He added: "Above all, we would like to get to know the end-user; it’s the perfect way of making further improvements to our products.
"There are very few faults, but we do need to know about them when they do arise."