Lessons in Boat Patience – technical stuff

As Gwen mentioned in the previous post, we had a couple of interesting problems over the Opening Day weekend.  I keep telling myself that it was good to have these issues in a place where we can get parts and service.

Domestic Water Pump

The simple, but annoying issue was the failure (again) of our domestic water pump.  This is a critcal piece of equipment not only for the operation of all the sink faucets, but also for the operation of our marine heads, which use fresh water to flush.  Honestly, I’m surprised that Gwen didn’t wake me up on Friday night to replace the pump after it gave up the ghost. (Thanks!)

The pump is a variable speed pump made by a company called Jabsco.  It is very fancy, and relatively expensive.  The benefit of a variable speed pump is that it allows us to avoid having a bulky accumulator tank in the system.  This model of pump has been notoriously unreliable for us – we just replaced it in February, and also replaced it last summer.  Unfortunately, I didn’t put the spare pump we ordered in February back on the boat, so it was off to Fisheries Supply.  My friend Ted also had the same Jabsco pump, also had multiple failures, and eventually replaced his with a Johnson pump, which he is very happy with.

When I showed up at Fisheries and told them about the issue, the “pump guy” gave a knowing look, and took me right back to the Johnson pump, which is a “drop in” replacement for the Jabsco.  And so it was, except for having a different mounting pattern.  So, a few holes drilled and in it went, super easy… except that the tabs that secure the input and output ports were missing!  Fortunately, I was able to reuse the ones from the Jabsco pump.

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The Johnson pump in place.

I’m not sure that we are done with this saga.  The Johnson pump is not particularly effective at maintaining a high flow rate.  It surges and then slows down, which may be problematic for taking showers, etc.  I wonder if it might be defective, so am contemplating taking it back to Fisheries for a replacement.

Battery Chargers and Generator

As I mentioned in a previous blog post, one of the work items in our trip to the boatyard was changing the batteries from Lifeline AGMs to Firefly Carbon Foam and adding two Victron 100 Amp chargers.  The goal was to allow the Firefly batteries to be recharged as fast as possible, minimizing generator runtime at anchor.  I had the chance to put the system to the test by accidentally discharging the batteries to nearly 90% overnight (left the engine room blowers on).  So, I start the generator in the morning, and flip on the breakers for the chargers.  I immediately see the batteries getting charged at a rate of 300 Amps/hr, which is exactly what I was hoping for.  Awesome… until both the breakers for the Victron chargers tripped… repeatedly.  It turns out that each charger was installed on one “leg” of our 240VAC outputs from the generator to balance the load.  Fine.  But, the breakers were rated for 15 Amps.  The Victron installation manual clearly states that the charger draws 15 Amps of 120VAC current to deliver 100 Amps of DC charging.  I suspect that the breakers were undersized for the application.  Not a big problem, I thought, since the exisitng Magnum Inverter charger was still working, putting out 120 or so Amps of DC charging.  It will just take longer.  After a couple of hours, I tried turning on the Victron chargers again.  This time the charge rate was low enough that the chargers were not pulling maximum current, and the breakers did not trip.  All good, I thought, and went about preparations for the day’s festivities.

Miranda’s friends arrived and she asked that we set up a lounge chair that can be hung from the davit.  No problem, as the generator was already running (the davit is powered by a 240VAC motor so needs the generator to be on to operate).  So, I moved the davit into place, rigged the chair and got ready to lift it… and…. nothing.  Davit is dead.  Checking the AC panel in the pilot house, I see that my voltage reading is at 120, not the 240 that it should be with the generator running.  I had somehow overloaded the AC circuit and had “lost” one of the two 120V legs that combine to give 240 volts.  This was a bit of a mystery, given that I knew of no way to switch a leg on or off.  It was usually 240 or nothing.  I could not find the problem, and what was worse was that the “dead” leg was the one that supplied the Magnum inverter/charger.  Thus, no AC power for things like refrigerator, freezer, etc from the generator, and the batteries were still deeply discharged, so running them from the inverter for another 24 hours would kill the brand new batteries.  This was a bit of a problem.  But then I remembered that one of the Victron chargers must be wired to the leg that was still working.  So, turn that one on, and yes, we are charging… for about 30 seconds, until the breaker trips again.  Now I am really wondering what to do.  I look at the panel and notice that the breaker for the watermaker is just above those for the chargers, and is a 20 amp breaker.  So, I disconnected the power for the watermaker, and moved the power lines for one of the chargers to one half of that breaker.

IMG_7058
Rewiring the Victron breaker.

That worked, and thus we were able to keep charging the batteries with the one Victron charger while running the “house” from the inverter.  I was able to determine that the generator itself is still putting out 240V, which is good news, but was unable to find the fault leading to the panel.  Bottom line is that the boat is going back to the yard next week to have this addressed (along with several other items that did not get completed last month).

 

 

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