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The two old, leaking hot water heaters that needed to be removed.

The two old, leaking hot water heaters that needed to be removed.

Easter Weekend, I decided to tackle a large project that I had been putting off for nearly a month – replacing the hot water heater in the engine room. This had been in the back of my mind since the day I took Sea Eagle down to Olympia for bottom paint. I had arrived on the boat, only to find the floor of the engine room covered with engine coolant. Oops! That could only mean one of two things, either a leaky keel cooler (very bad) or the heat coil in the hot water heater was leaking. When I isolated the hot water heater, the overflowing coolant stopped, so I knew that was the problem.

I special ordered the replacement unit during Defenders annual sale and then looked around the engine room trying to figure out the best way to tackle the project. There were two hot water heaters in the engine room. A small, square Isotherm unit that worked off the Generator (decommissioned last year due to leakage) and the 20 gallon Raritan unit tucked way back in the corner behind the wing engine.

Victory is mine!  Both of the old hot water heaters were successfully extracted from the engine room!

Victory is mine! Both of the old hot water heaters were successfully extracted from the engine room!

The first task was to remove the Isotherm Unit, which proved a little tricky as the outside mounting bolts were very difficult to access. Perseverance paid off and once the coolant hoses were plugged and the spilled coolant was cleaned up, it was time to tackle the big unit.

The large heater had been in place for ten years, so many of the fittings were corroded and took a lot of persuasion to remove. Eventually, large pipe wrenches were able to persuade even the most stubborn fittings and I was able to just squeeze the old heater out by going over the top of the wing engine at an angle.

The new 20 gallon, 240 volt hot water heater, installed and working!

The new 20 gallon, 240 volt hot water heater, installed and working!

I hauled the new unit in, using the same serpentine and angled path, then made a quick trip to West Marine for some new fittings to replace the corroded hose adapters going to the main engine coolant. The heater was wired and plumbed up and filled with water. Of course there is always one leak (the pressure relief valve which I had torqued the piss out of), but bigger wrenches convinced even that to stop.

I turned the unit on and soon had toasty warm water again to wash my hands after cleaning up the giant mess that I had made! Hopefully, I’ll get another ten years out of the new unit before I have to tear it apart again! I’m thinking I’ll check the aluminum anode in the heater annually, just to be sure!

Ever wonder how the heck you get a large hot water heater out of the engine room?  Through the floor of the Saloon.

Ever wonder how the heck you get a large hot water heater out of the engine room? Through the floor of the Saloon.