Disco-inspired safety check
I have just read about the danger of cheap exhausts bought online and fitted to marine diesel heaters (PBO May 2022).
It isn’t just cheap exhausts that cause a problem – time, and a marine application can corrode even the most respected models.
We own a 20-year-old Fairline Phantom 43 fitted originally with a high-quality diesel heater. I replaced the whole system two years ago. Before replacing it I smoketested the old system using a disco smoke machine (apple flavoured smoke – not essential!) To my horror the stainless steel insulated exhaust leaked like a sieve. When I removed the old exhaust and insulation there were hundreds of pin holes in the section from the top of the swan neck to the outlet.
We have a carbon monoxide alarm in the main cabin which was never activated when the old heater was running.
I hope to warn others that even the best quality stuff eventually wears out! Many owners of older boats don’t get their heating systems professionally serviced and just tend to replace parts when they fail. Often the exhaust runs are difficult to access and therefore difficult to replace.
On my boat I had to remove some of the 240V systems, move the starboard water tank and remove the gas locker to get access to the whole exhaust for replacement. It was a big job. Much easier to ‘bury your head in the sand’ and hope everything is OK.
I can hear some boat owners groaning over this suggestion as it might result in significant expense to replace the faulty exhaust – but what price is safety? Dr Paul Roper, via email