Refrigeration A25

[Beta Don]

In our cruising we've seen several boats running a small gas genset sitting on the swim platform. You can screw appropriate sized bottle caps to the platform for the feet of the generator to sit in and that will keep it from vibrating off the platform - A rope tied to the swim ladder for added security would be a good idea too. If you run it completely out of gas after each use, you can store it below in most any location you can find to fit it - Even under a bunk or under the dinette - Far cheaper than the 2.5 Kw diesel genset we installed on our A27

If you have a 50 or 60 amp 'smartcharger' for your house batteries, you can power that with a 1 Kw genset to get some significant recharge while on the hook - 50 or 60 amps per hour of run time. A 10 or 15 amp house bank charger is fine for when you're tied to the dock, but it you anticipate the need to recharge on the hook, a much larger charger will save you both time and gas. A 1 Kw will also run a small microwave and it can heat the water in your water heater for a shower too. A 2 Kw can probably even run your air conditioning. I have a Honda 2000i and while we've never used it on the boat, it will run several hours on a quart of gas, depending on the load. We saw lots of people using them and I think if I had it to do over again, I would go that way. We surely didn't get that much use out of the $4500 we spent on the little diesel genset we installed

Don

[Sunsetrider]

Generac-6719-IX-2000-Watt-Portable-Inverter-Generator.jpg

I went ahead, prompted by a sale at Loews that was ending today, and picked up this:
http://www.planetgenerators.com/generac ... 00-review/
for $719 CAD.

I might have to somehow construct a raised platform off the swim platform to keep it clear of the waves. I'll figure something out.

[Halcyon]

I visited a local Honda dealer and told them it was a boat application. The salesman said the only way he would use a portable generator is if it was in a dingy with a long cord. He was very concerned about carbon monoxide blowing back into the boat.

[JT48348]

There's a lot of people afraid of a lot of things. I'm reminded every time I turn on certain news chanels.

Theres detailed discussions on the pros/cons of portable gas generators on boats in various forums. Its a personal decision requiring some understanding of the facts and risks associated.

I do know, I'd find another generator salesman.

[Sunsetrider]

Not entirely sure what the difference would be with the engine of the boat itself blowing CO2 back into an open port or hatch. I don't think we run either overnight while asleep.

[DesertAlbin736]

I visited a local Honda dealer and told them it was a boat application. The salesman said the only way he would use a portable generator is if it was in a dinghy with a long cord. He was very concerned about carbon monoxide blowing back into the boat.

A valid concern. CO (carbon monoxide) has long been known to be a problem with houseboats running gensets, even built-in ones, while occupants are swimming nearby. Like propane, CO is heavier than air & sinks. But unlike propane, you can't smell CO.

Carbon Monoxide & boating:

https://www.cdc.gov/niosh/topics/coboating/

The good news for us diesel boaters is that our diesel engines, assuming they're in good running condition, produce far less CO than comparable gas engines, and our A25 & A25 boats use much smaller horsepower engines that comparable length gas engined planing boats.

Is carbon monoxide a problem with diesel engines? Usually not, although any engine, including diesel, produces CO when combustion is incomplete. Diesel (compression ignition) engines run with an excess of air and often produce less than 1200 ppm CO. When diesel fuel is burned incompletely or when overloaded and over-fueled (rich mixture), diesel engines will produce high concentrations of CO. Diesels usually pollute the air with particulates and nitrogen oxides, not CO....A gasoline engine producing 10,000 ppm CO at the ideal air-fuel ratio will produce over 60,000 ppm when the fuel is increased. Other causes of high CO production include; a cold engine, misfiring, incorrect engine timing, defective or worn parts, exhaust system leaks.

https://www.abe.iastate.edu/extension-a ... s-aen-206/

[Sunsetrider]

No question portable generators pose serious risks which must be addressed. Fortunately there are many private and gov-sponsored articles on the precautions to be taken and the dangers to be alert to in order to avoid mishap or tragedy. Risks include spilled fuel, CO2 poisoning, ancillary fuel storage. Being alert to the dangers results in mitigation, as is the case with many serious dangers associated with boating. I think of those risks every time I am about to start the engine on my I/O bowrider! Or when there are young kids aboard. Or when I use the propane BBQ on the rail. Or when we get lost in unknown waters. But we have "plans" in motion to address the known risks.

[Northern Spy]

We did the Eu200i honda on the swim platform a few times with our old boat. It's a pain in the butt, the whole boat reverberates with the generator running. We hardly used it at anchor cause we were too busy having fun, about the only time we used it was to run an A/C unit tied to dock without power. We managed our then built in fridge power consumption by getting out what we needed while underway allowing the temp to drop then shutting it down while anchored for a few hours.
So far our most practical setup has been the portable fridge on a big battery bank with a cooler for drinks.

[Sunsetrider]

I can't say I haven't thought about the scenario that you paint, Northern Spy. Whether I should return it and focus the money on a larger battery bank instead. It won't operate efficiently through my 12A charger anyway, and I will need to do some major work on the platform to use it there. My need (or not) is in relation to a lengthy voyage, not for day or weekend tripping in home waters, however. But I need to make a decision soon. Or do I keep it around just to have one of these for the various other uses they might have?

Then again, $700 buys a lot of battery power . . .

[Jay Knoll]

we have 4 55 watt solar panels on the hardtop of our A27, 2 4Ds in parallel for our house bank and a series 31 (I think) starting battery protected by an ACR. A 2000 watt inverter rounds out the system for those instances when we need AC power. I run an Isotherm unit to cool the ice box. The system has worked flawlessly for us, we rarely have to plug in to charge the batteries. Not having the boat plugged into shore power helps reduce galvanic corrosion (I think, I'm sure that some more qualified members will weigh in on that subject)

The solar panels are silent, and I don't have to carry gas or a generator.

[Sunsetrider]

That hardtop on the 27s comes in handy. Not too many likely places for a large array on the 25. I believe a 100W panel wouls be the minimum to back up the batteries to power the fridge/freezer, and that is a unit being sold by the Unique dealer - to pair with the fridge.

[Sunsetrider]

So I think I will return the beautiful orange thing on my dining room floor, repackage it, and get $750 back to pay for batteries etc. I need advice on this plan going forward:

Existing setup:
- newly re-wired battery room with 1 start battery and 1 115AH house battery, controlled from the alternator with a Blue sea ACR, controlled from the deck with a Promarine Pro550 12A dual-battery smart charger, new 12V breaker panel, minimal draw on day trips. Plan to switch to LED lights throughout, including anchor light. 2 small 12V fans. Alcohol 2-burner stovetop, propane BBQ. Basic electronics, 2 12V plugins (cig).
New to come:
- Unique portable 60 l. fridge/freezer (2.5 AH draw, they say)
- would like to run a small M/wave, maybe a pressure cooker

The fridge retailer also sells a 100A solar panel which I can maybe fit onto the bow area, but 2 smaller ones would probably fit better. I figure with the return of the genny I have $750 (CAD) freed up for battery and solar, so that should be plenty budget-wise. (?)

So thinking to link a pair of golf cart batteries in parallel to the existing 115 AH house should give me enough battery power? 100A solar should be able to keep the batteries up to speed with the fridge?

And a 2000W inverter to power the occasional 100V appliance.

Will this work?

[Beta Don]

Yes, if you're not going to invest in a high amp smart charger, a genset would be of little value, other than to use to run air conditioning or a microwave or an electric cooktop. It would take many hours with only a 12 amp charger to top off your batteries. Your fridge might be using 30 or 40 AH per day and you'd need 3 to 4 hours of run time to replace that amount

We were moored next door to a 25' sailboat that a couple with a 4 year old were living on in Marathon. They ran a small genset sitting on the foredeck every single day for 2 or 3 hours and I don't think they had any form of DC refrigeration - He came home from work most days with a couple bags of ice

Paralleling batteries (directly connecting them positive to positive and negative to negative) isn't a good idea - That's why ACR's were invented. If you're talking about brand new, identical batteries wired in parallel, it's not THAT bad (still not a good idea though) but if you were paralleling new golf cart batteries with a different type used battery as it sounds like you're thinking of doing, it would be a really bad idea. When batteries are directly paralleled, there is a small amount of electrical activity going on all the time - The stronger, newer battery is always 'trickle charging' the weaker, older battery and that greatly shortens their lifespan. Even when done with brand new identical batteries, as they age one will eventually become a weaker battery than the other and the resulting electrical activity will shorten the life of the better one

Using a battery switch (or an ACR) to put them in parallel while you are charging them and then disconnecting them when the charging source is removed is the best way. I've seen boats with several battery switches using complicated pairings for charging and daily use - Better to use 2 or 3 ACR's IMO

I have no idea of the space you have available, but if you can fit a pair of golf cart batteries, maybe you have space for a pair of similar, but taller batteries? The L-16 format is a great choice if you can squeeze a pair of them aboard somewhere - Twice the capacity (400 AH) of a pair of GC's and they would run your fridge for several days. Four GC's would give the same capacity as a single pair of L-16's

AGM golf cart batteries can be used and mounted most anywhere, since you'll never need to get to them to periodically add water and since they don't emit gas when they are charged, they can legally be mounted within the living space on the boat

If you go to bigger batteries with lots of AH's, a higher output alternator on the engine would be a wise move - That way, if you find you do need to occasionally run the engine to recharge, you would be getting twice or three times the charge amps of a standard alternator. Single wire, 100 to 120 amp alternators can be found on eBay for $100 to $125. They sell even higher rated alternators (150 up to 200 amps) but it's not practical to use anything much larger than 100 amps if it's to be driven by a single belt. High output alternators can be hard on drive belts

Smaller solar panels are pretty inexpensive on eBay - Mounting the largest pair you can fit on the roof would be a very good idea. Even if all you can fit would be a pair of 50 watt panels, you could probably see 15 to 20 AH of charge on a good day. That will make a nice 'dent' in the power your fridge will use and it would extend your time at anchor without needing to run the engine

A 2KW inverter would draw roughly 175 amps from it's battery source at full song - A 100 AH battery would not put up with that for more than a few minutes before the inverter had a low voltage shutdown. Even powering a small 800 watt microwave, the draw would be around 75 amps - 20 minutes of that sucks up enough juice to run your fridge for half a day or so. Inverter use is a HUGE load which rapidly depletes even large battery banks, so it needs to be kept to a minimum. Peukert's Law comes into play with higher discharge rates - A rated 200 AH battery has less actual amps when powering high draw loads

Don

[Sunsetrider]

I don't think I want to be lifting those L-16s and I don't think I need that level of power. But it makes sense to stick with similar so I am going to go with 2 sets of T-105s and a start. I think I will have room for them in the battery area below the helm. I have a lot of work to do to find and fit appropriate solar panels. I really don't want to fool around with alternators at this point - mine looks new and I don't want to start pulling things apart at that end of the engine, other than sourcing a belt as a spare part.

You confirm my understanding of the inadequacy of the gen in charging through the 12A charger.

[WillieC]

Sunsetrider, just saw your post on Cruisers Forum and I had to go back and check to see what engine you have. MD17C, correct? One limiting factor in your electrical upgrade,(FOR the REFRIGERATOR, see, I'm on topic) is the skinny little Volvo Penta belt that drives the alternator. It is able to handle no more than 70A as is. That was also one of my early brakes in my electrical redo. The stock on my boat was an anemic 35A Franch/'mer'can unit that I am fairly certain was original, though not Volvo Green, so maybe not, but it was old. I went to my local starter/alternator shop and upgraded to 60A. Plain Jane, likely Chinese, internal regulator but marinized! I need to do more with my system, but, like you, I find the more I read the more I get confused.

Keep this in mind as you move forward. I think right on top of larger than original alternator, you should try to understand what an external, tweakable regulator can accomplish so you get the most out of the alternator that your belt can drive. And carry extras. (Belts and alternators?)

My off the shelf cheap-o alternator looked like an exact fit, so I didn't do much more than bolt it in (along with my primary rewire job.) Now that I have the refreshed engine ready to reinstall, sitting out there on the shop floor, I thought I'd look at the alternator alignment with the flywheel. After I installed it on the old MD3B in the boat, black fuzz started showing up, which I wrote off as a heavier load on the belt. Well, no, it was actually a good quarter inch out of parallel to the flywheel which was easily corrected by trimming the alternator bolt-up point. Much easier to see out of the boat.

Sorry if this is all old news to you, but this little factoid took me a good while to ascertain. Keep at it! Can't wait to hear about the Great Adventure.