Hot water tank strikes again

Saturday 19-Mar, Honduras day 17, Roatan, French Key Harbour: Battling with the hot water tank… again!

Two days ago, we traced the source of the bilge leak to the hot water tank safety valve. Over the last 24 hours we had the draining pipe from the safety valve placed in a container so we can gauge the full extent of just how much fresh water we are losing a day. It’s a lot! Something needs to be done. Today!

The obvious first move is to turn the knob on the valve, which allows it to free flow, and hope this will clear any “thing” that might be causing it to leak. But, sadly that action has the opposite effect to the one intended. The action changes the “drip-drip-drip” leak to a steady constant flow. And when I try yet another reset, the flow turns into a gusher, causing the water pump to be constantly on. Damn and double damn! We could have lived with the drip-drip … but not this! Sometimes it’s best to just leave problems alone ☹

Of course, like most things that fail on the boat, this safety valve is almost inaccessible, in amongst a maze of plumbing underneath the how water tank. So, same as the last one that started to leak (yes this is the 2nd time now!) I have a solution. I simply place another safety valve on the end of the drain hose. That stopped the leak last time, up until the time I could change the valve properly. But this time, the back pressure on the failed valve caused it to totally fail with water now gushing everywhere ☹

So, as much as I HATE removing the hot water tank, I have no choice. At least, no choice if we want hot water in the coming weeks. This, in fact, will be the 4th time I’ve removed this damned tank. So the good news is that I know exactly what it takes to do the job, and 2 sweaty hours later the tank is out and resting on the top of the Volvo, ready for surgery by yours truly. The other good news is now that I have it on the operating table, I can also replace the emersion heater and thermostat which have also failed, leaving only the engine to heat the water.
You may be surprised, but I do have both a spare emersion element, a spare thermostat and also a spare (2 in fact) safety valve. One has to be prepared!
Putting in the new heater element and thermostat was surprisingly easy. I just needed my biggest wrench to undo the 55mm nut. But pulling all the plumbing apart so that I could replace the safety valve was anything but easy without having a big vice available. This led to a lot of cursing and also quite a lot of bloodletting from various cuts on my hands.
Long story (and loooong day) short, I removed all the plumbing, cleaned each thread and put the whole lot back together, sealing each joint with Loctite 275. But this time I have made a modification. The safety valve is now on the end of a flexible pipe, such that if/when is fails again, it will be very easy to replace. But by Murphy’s Law, now that I made this modification, I’m certain that valve will never fail again! Fingers crossed.

By the evening the tank is back in place on the engine room wall and all the associated piping and wiring ty-wrapped neatly back in place. But we don’t fill the tank just yet. We will leave it for 48 hours for the Loctite to fully cure before filling and pressuring up to its 3bar working pressure. If it doesn’t leak, it will be a major item ticked off my to-do list. If it does leak … well, I may just walk myself off the plank!