Nardi dive compressor tested

by Glen

Wednesday 12 Jan, cruising day 46, Key West: Marooned aboard again. Test new dive compressor and do a spot of sewing.

Windy again today. We had thought getting this far south would lead to calmer weather, but not to be. The cold fronts just keep on a coming, day after day, and the next several days look the same. Today it blew 20kts all day again. I can find a reasonable weather window to get to Mexico but the complication is our desire to visit the Dry Tortugas before that. We could jump there on a calm day and wait out the next blow before heading to Mexico, but I’m really not sure anchoring there would be safe in 25-35 kts NW winds. Ho-Hum … we will just have to keep looking at the forecasts.

Windy also means no trips ashore again. Others around us do go in, but it will be a very wet dinghy ride. No problem for me though – I could spend a month-of-Sundays on the boat and still not get bored. There are never enough hours in the day for me!
I spend the morning on the internet. We received an email from Reckmann today, saying that our generation of vang had a poorly designed sealing system. They recommend anyone asking for a service to buy new or accept no warrantee for the service. Well at least I know our problem now. I then ask around other HR54 owners regarding what vang they have and if they had any issues similar to us. From the replies, it seems many have had leaks also, but a service seems to have fixed them. Though compared to us, I really wonder how much hard sailing they do. Because we only started having issues when sailing in the big Atlantic waves where, when sailing off-wind, the vang really works very hard, constantly going back and forth from compression to tension as the boat rolls.

In the afternoon I decide to give our new Nardi dive compressor a proper test. Thus far I have only wired it directly into the generator via a K-Curve breaker and run it briefly to see if it would start OK. Today I will actually refill the dive tanks. First, I let the old air of out the tanks, then move them into the cockpit. I have the airline setup, so that it runs from the compressor in the engine room up into the pedestal where it exits out of a small door and attaches to the tank and pressure gauge in the cockpit. Unfortunately, this high-pressure airline is a little short, so I can only connect if the dive tank is horizontal. When I see dive centers filling tanks they are always vertical and I wonder if horizontal will be OK, at least until I get a longer hose.

With the generator running and warmed up I try to start the compressor. The generator instantly gives an “over-current” alarm, the K-Curve breaker trips, and the generators automatically shuts down. Hmmm, not good. But then I realise the tank still has 100bar pressure in it, and the compressor is trying to start up against that pressure. With the pressure bled down, it starts perfectly. And once running it is happily filling the dive tank, with the generator running at an easy 16amps (@230vac). In the end I even manage to power the water heater and 20% of the battery charger at the same time. But then I push it a bit too much and the generator instantly stops ☹ This time with an “under-voltage” alarm. And, it won’t start again. Poor thing. It was certainly not good for it to shut-down while under maximum load. Clearly I need to let it rest and cool down for a while.

30 minutes later, to my great relief, it does start OK. As I fill the next tank, I monitor the voltage output from the generator very carefully as I gently load it up. And I discover that as the compressor starts it instantly pulls the voltage down from 235vac to 210vac. There’s the problem. That’s a clear sign that either the large capacitors on the generator or the one on the compressor need to be changed or increased. We had this issue with the water maker when we first got the boat. I’ll ask Nardi Tech support’s advice first before I go dabbling with my non-electrical hands.
At the end of this exercise, I have to say that I’m very happy the compressor managed to fill the tanks. Especially after FedEx had dropped it and damaged it during shipment. And at 100cfm, it was pretty quick. Only about 20 minutes per tank, from 0 to 220bar (3000Psi).

Next job is sewing. I’d recently made drop-down side shades for the bimini, but now want to add tabs onto them, so when not in use we can roll them up and fix them in place without removing them from the bimini. I get the tabs made and sewn on, but unfortunately my set of metal snap-poppers are not robust enough to go through the many layers of material. So it will be off to a canvas shop tomorrow. Then a decent popper installation tool will be on my next to-buy list from SailRite.

In the evening I was determined to continue with video editing, but somehow the evening zipped by without time. Like I said, never enough hours in a day for me, the busy-bee.

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