It might be perfectly acceptable to use PVC plumbing fittings on the vessel's fresh water system, but if one was to fail, I would still be rather upset if the contents of my water tank were to sit in the bilges for some weeks whilst un-attended on her mooring. However, during my survey work I often come across more serious situations like the one shown in the photograph below. It's not uncommon for an owner to search amongst the shelves of a chandlery, looking for a marine-grade fitting of a specific size. After a frustrated search he finds what he's looking for, but neglects or forgets to consider the items' suitability for the application.
In the situation shown in the photo, a domestic plumbing fitting has been installed in a location that is below the waterline. The hose and fittings (un-reinforced hose and with single clips) are for the generator exhaust coolant outlet on a 51' motor cruiser. Even above the waterline, this situation could cause significant ingress of water if the relatively weak fitting were to fail: The generator's coolant would be pumped directly into the engine room and is also in close proximity to the vessel's batteries. In the situation shown, the hose attached to the 'un-reinforced PVC fitting' would drop down, allowing water to flow into the boat.
In this example, the skin fitting is about 12 inches below the waterline and the internal diameter of the hose is about 1 inch. For a length of hose such as that seen in the photo, the resulting flow rate will be around 9 gallons or 4 buckets of water per minute. Of course, the vessel's pumps may be able to handle this amount, but in this case a few low cost preventative measures would minimise the chances of this scenario occurring.
For advice on the installation of your vessel's skin fittings or through-hulls, contact fieldhouse-yacht-surveys.com
For advice on the installation of your vessel's skin fittings or through-hulls, contact fieldhouse-yacht-surveys.com
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| Generator Exhaust System |
