Posts Tagged ‘Refrigeration’

Stasis

Thursday, May 26th, 2016

We’re now in the water and slowly working on bringing the rest of our systems online.  Mostly the refrigeration. And silly me; I look for the easy way.

While both systems; the DC and the engine driven compressor, have lost refrigerant there is still some pressure in each. Unfortunately there was very little in the engine drive system and in hindsight I would have been wiser to simply evacuate it and recharge, but I was trying to keep things simple and figured I will just add R-134a till it all works right. Silly me.

I added, I removed. I hadn’t put my professional gauges on and was using a wonky car AC gauge to read only the Low Pressure side.  I ran the system. My sight glass showed bubbles; low refrigerant. Finally, I dug out the gauges and connected them. Whoa!  I was still way low. I added another can. Still low. I ran the system and I was still low. I added another can of refrigerant and watched  the sight glass.  Finally after the can was empty the sight glass foam disappeared. But the glass was still a bit foggy so I finished the refrigerant in the can. The system ran fine and the pressures looked good.

The following run time the HP went up to about 200 lbs. Real close. Oh-Oh!  Now I have appeared to have added too much refrigerant.  Luckily  the high pressure switch did not shut down the system and as the temperature on the plates cooled the system down everything looked good. The refrigeration compressor still made a bit of a grinding noise; like rust on the clutch, but over time the noise was diminishing so I felt it best to leave well enough alone. On a boat my philosophy is simple, “if it ain’t broke, don’t fix it”.  Right now it “ain’t broke”.

For the next couple of days we watched it. I now have enough refrigerant left to do a complete recharge but that is it.  I do have a new compressor to install if I need to.  That would mean dumping what is in the system, evacuating, and recharging the system with the end result that I have no more

Refrig Comprssor on Generator

Refrig Compressor on Generator

refrigerant for spares. Oh, I can buy refrigerant here; but not in the small easily stored cans, only in 10 kg containers. That makes storage a bit of an issue.  The other issue I faced is that of evacuating the system.

While I have a vacuum pump, it runs on 120v 60 cycle electricity. The electrical system here is 240 volts 50 cycle.  Which means I need to run the pump on ships power for about 3 hours and that is near the extent of my battery bank. My minimal solar will not keep up with the power drain of evacuation.  As I would be evacuating the system attached to  the generator I don’t want to use the generator to charge the batteries. Too many spinning belts too close to where I would be working.  Now, if push came to shove I could do it; but right now I’m being nudged and not shoved. Patience, I will be patient. I WILL BE PATIENT! 🙂

While working on the refrigeration systems we were talking to Simon (the activities directory – sort of for the Boatshed Restaurant).   Simon presented a couple of  events that we attended.  During the Fijian History lesson we brought up the idea of visiting some of the places he had mentioned.  He was all for creating a tour and we tentatively  cleared it with Adam the Marina manager. Simon set about scheduling transportation and accommodations for  8-10 cruisers.  W/ signed up 8, one ended up with an infection from of all things gardening. and so we were down one couple.  Six of us went on a unique tour from Vuda to Suva and back.

Go Slow
Sail Far
Stay Long

I’m Not Dead Yet!

Wednesday, August 8th, 2012

I know it’s been a bit since my last post. Sorry. I’ve gotten wrapped up in a long tomb of books; the Wheel of Time by Robert Jordan. Each book in this damn series is 300k  + words long and there are something like 14!  I’m on book 13 and the good news / bad news is that the last one will not be published till Jan of ’13!

Besides that we’ve been struggling with the refrigeration system. For those bored with sitting at a desk and want to see what real world problem solving is like they can read the discussion.

And while I may have a bad compressor I’m still learning about the system and will know more when this issue is finished. Maybe I’ll end up as our friends on  Infini did and just switch it all out for two simple evaporator plate systems. Who knows. But I hate, HATE, HATE, admitting that I made such a grave error in outfitting the boat that we’ll end up discarding this “Gold Plated” holding plate system from Sea Frost and switch. The other option is to get  really large evaporator plate from Dole and replace the smaller one in the freezer with some dead space under it. Then the inside wall of the freezer would all be holding plate and maybe, just maybe, I could get down to running the generator once / day. Maybe!

Speaking of; while evaporator plates are much simpler and demand much less peak energy to run although close to the same daily amount,  they tend to have electronic modules that can be harmed by close  lightening strikes. So as in all things yachting. There are compromises.

Two projects I”m working on to share with the boat community and friends: 1) Awnings, and 2) Costs.  I hope to have them completed sometime this month and posted. Cruising costs are always available on my website and usually don’t end up more then 4 months behind.

Anyway, W/’s been working on bulk photos and has put them up on her  Facebook photos. They are:  Sapzurro Colombia, Spring Summer 2012, , Isla Pinos, Hike with Lisa, Tigre Revolution Reinactment, Grouper Tail, and Carti to Panama City. Those are for public viewing so you may check all out that your heart desires.

And while we hang out here in Puerto Lindo we do have much easier access to the civilized population areas of Panama and a 3G cell phone network which we’ve enjoyed. It’s almost like being in a modern Westernized Country. Almost…..

Go Slow
Sail Far
Stay Long

Addendum: Received and email from svReach concerning the lightening and refrigeration systems. He’d been struck last year; with a great deal of elecrtrical damage and yet had no damage to his refrigeration system. Further several boats here on the N Coast of Panama had been struck and only one had a refrigeration issue. Mark (from svReach)  had indicated that about 10 years ago the manufactures all switched to using the Danfoss system and the Danfoss control boards. Those boards are in a grounded Aluminum box and thus maybe better able to handle  Electrical Magnetic Pulses better then any of the old styles. However;  he also indicated that he carries a spare board just in case!

Almost

Saturday, July 21st, 2012

One of my goals this season had been to ensure the boat could  cruise a full  year without major issues. A major issue is one I can’t fix and forces us  to  high tail it to the nearest port where we can effect repairs.  We didn’t make it a full year but we came close.  We have had a few rather serious (not catastrophic)  issues.  The exhaust elbow in the generator has a smallish 2 cm crack.  I  fixed the crack with JB Weld that held  for a bit but it didn’t last more then 3 months and so I’ve re JB Welded it and put a cover over it so there is no spray, only dribbles. Till we get to the marina it will remain 1/2 fixed.

Then, the genset’s heat exchanger began to leak.  It’s an older style heat exchanger and now looking back I see where I could maybe have lucked out and recognized there was a Zinc in the heat exchanger.  Two of the three pictures in the Aquagen instruction manual identify a drain at the bottom of the exchanger and the third one now shows a Zinc.  The solder has  been etched away and now I has a leak.  I’ve since rubber clamped it shut so it will not leak and will send it back to Aquamarine for repair when we get back to the states. In the meantime I’ve ordered and received a new heat exchanger, a new model and it has a Zinc of which I need to  purchase many more and make sure this doesn’t happen again.

The High Pressure pump (HP) on the water maker leaks.  My error.  I had found difficulty with the original boost valve (it was of a lawn sprinkler valve and I had put the valve in  vertically when it needed to be below water level and horizontally – not well documented in the manual), so I had replaced it with a manual valve.  One time running the water maker I forgot to turn the valve on to start the system and this caused excess cavitation in the HP pump. Thus a small leak. I called Dan (of Aquamarine – and that is one great thing about the company — I can speak to him about any issue most anytime), and he indicated that I needed to get a new gasket kit.  I now have that and a spare and will replace it when I get to Shelter Bay Marina. It’s the rainy season now and we can catch plenty of water.

In the last 2 weeks  the Aquagen began to crank over ever so slowly and finally it just wouldn’t turn over the engine. I knew we had plenty of power and suspected the starter we had fixed (almost) in Panama City. There they didn’t have a replacement starter but we found one that appeared the same size  and I put that starter motor in  the housing I had. However; I don’t believe the front bearing was ever replaced.  The starter worked but it took about 5 seconds on the glow plug and then it required about 5 seconds to turn it over before the generator would catch and 90% of the time or more I would hear teeth grinding as the starter disengaged. Well the replacement finally wouldn’t do the job.

Thinking ahead while back in the states I purchased a new replacement starter for this engine and had kept it as a spare.  Fool me once shame on you, fool me twice shame on me.  I replaced the Panama City starter and viola!  I turned the key and the generator started just like new!  No longer did I need to hold the glow plug on for 5 seconds, in less then a second or two she fired right up. Sweet.

And about this same time I had taken some refrigerant out of the engine driven system and bought some fuel from a gas station in town. The refrigeration system was overcharged some and we were having to run the generator longer then we needed. When it’s running correctly we run it approx 45 minutes in the am and 45 minutes in the pm. With the overcharged state we were needing to run it approx  80 minutes am and pm. The extra time was a PITA. So I pulled out  approx 5 psi and the generator ran fine that evening; the refrigeration plates pulled down faster, but not yet perfect.  The next day we added 25 gallons of diesel to the tanks.  The next time we ran the generator to pull down the plates in the freezer and the ice box things began acting weird.  The rpms on the generator began to vary and once they went so low as to stall the engine. I suspected the new fuel.

Running the generator with the refrigeration compressor (RC) on, we heard some significant changes in engine rpms. It seems that both W/ and I are extremely sensitive to small sounds and how they end up telling me to find what’s wrong.  We shut the system down and I figured the fuel filters were getting clogged. Fuel was the last thing added and the last change to the engine.  Diagnosing issues on a boat isn’t a lot different from diagnosis in terms of computer issues or I suspect any other field where one has to problem solve.  It is a lot like playing 20 questions. As long as you ask simple questions and learn the answer you can solve the problem. Working on several things at once and then trying to  identify  the issue would  easily have me fumbling all over the place. That is exactly what happened. Since the fuel was the last thing I did it was the first place I looked to solve the problem.  I was hoping to make it to our respite in Shelter Bay Marina before a lot of this smaller maintenance work, but as  teenagers today say “Oh Well”.  So before I figure I needed to, I first chose to change the Racor fuel filter. I changed that filter and the next time we ran the generator it did the same thing; varying engine rpms by about 300.  Ok, next change the fuel filter on the generator. and I did that.  Now the fuel getting to the generator will be crystal clear and yet the same issue occurred. Last thing in the fuel system would be the fuel pump. I had a spare. Whoopee!  I changed that too.

This time while running the generator and the RC when the engine started to bog down (damn it’s still doing the same thing)  I shut the RC off. Viola!  The generator ran as expected.  What the $#%#$ !  I wasn’t expecting this!  Now I know there is an issue with the compressor.

Thinking I still have a bit too much pressure in the RC system I pull out approx 5 more PSI and I email Mike on Abake. He actually has training in refrigeration systems and I email Dirk on Lison Life who knows more about mechanic issues on engines than I do.  The consensus seems to be that I have a RC that is soon to become  toast. DAMN!  (I actually have a more colorful vocabulary marching through my brain but do try to keep this blog PG).

In this process of checking the RC out I had hooked up the gauge set and ran all the numbers. They were well within range if not a little low on the HP side. To get a full set of numbers when the engine began to bog down I tried reducing the rpms a bit. I went down to 2500 rpms.  Again, Viola!  There was no more bogging down on the system and running the RC an hour gave me a full pull down on the refrigeration plates as well as a working set of numbers.

With Mike and Dirk saying the same thing that the issue was the RC I contacted Roger in Panama City to help locate a replacement. Roger is a Panamanian that is cruiser friendly. He had worked at the Panama Yacht club till it closed. Since then he’s made a career out of assisting cruisers in transporting and securing supplies.  He speaks fluent English and obviously Spanish  and he knows where the places are that cruisers need to stay afloat and happy. While he searched in the city  I called Sanden International in the USA and got the run around trying to connect to a real person on the phone, then found out they know almost nothing of the Sanden unit I have except they don’t make it anymore and they have no idea where a supplier is in Panama. So much for them being “International”!

So I waited. Roger called about 4ish  and had  found a similar Sanden sized correctly and hopefully W/ will pick it up today. While I wait for her return  I changed the oil in the genset and ran the RC successfully at the lower RPM. I’m wondering now if I run it at full rpm if I’ll still get the engine bogging down. Time will tell.

Go Slow
Sail Far
Stay Long