I have an ‘01 Sailfish that has the built in A/C. No idea how old it is and it doesn’t have any markings on it anymore. I works great on shore power but I’d like to get a little Honda or equivalent generator so that I can run it underway. Does anyone have an idea how many kw I would need? I don’t want to buy something oversized and obviously don’t want something too small. Thanks
Generator for A/C
- Thread starter SouthFork
- Start date
I'm sure any 2000W portable unit will work, but be sure to have CO detectors in your sleeping area.
Be aware naysayers will tell you you could die of CO, electrocution, HIV, and fire - all at the same time because portable generators are so dangerous.
Be aware naysayers will tell you you could die of CO, electrocution, HIV, and fire - all at the same time because portable generators are so dangerous.
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Check your electrical panel gauge, if you have one, when the AC compressor first kicks on. Note the amperage or watts. A 2000 watt generator at 120 volts only provides about 17 amps. I think my 330 AC needs a little more than that. 2000 watts may be marginally capable. If you find the name plate on the AC compressor it may provide the required amps/watts. Also consider any other items you would want to run with the AC. Add it all up and add 10% to determine your need.
Thanks guys I think I’m going to borrow a 2000 Honda from my dad and check it out. Family affair, 100% about the CO detector. I’ve been a firefighter for 25 years and have responded to calls where a generator ran in the garage or worse, in the home, and no CO detectors were installed.
Unless your AC has an excessively high start up current, I would think a 2kw unit will suffice. I would think the unit for a 272 would be a lot smaller than a 330 and requires a lot less juice.
The portable generators aren't without their risks, but many of those risks can be minimized further with some sensible precautions.
Looks like you are well aware of what Darwin Award contestants can do with a generator. Don't be them.
The portable generators aren't without their risks, but many of those risks can be minimized further with some sensible precautions.
Looks like you are well aware of what Darwin Award contestants can do with a generator. Don't be them.
Southfork, this is something I previously partially wrote and partially (well, primarily!) copied from a different forum. I am not saying to use it or to not use it - just offering some factual information (not the "I've been doing it for years and I'm fine thing") since you, being a fire fighter, likely thinks through the "what ifs" better than most of us. Most people will likely only read a few sentences, if any - but again, this is only meant as some educational material. We're all big boys and girls and can make our own decisions - but it's helpful to know all the facts, first.
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I agree that it's important to be aware of, and manage, your risks. But portable generators DO impose different risks than a properly installed genny. For one, when at anchor, boats will always face into the wind. Putting the genny on the bow means the wind will blow the exhaust toward the cabin, where you are sleeping. The exhaust will find it it's way in through - whether through small cracks in deck hatches or by the "station wagon" effect... down into the cockpit and will then actually go FORWARD through the cabin door. This EXACT scenario HAS happened in real life.
Second, an installed genny will exhaust out in one of two places: through the hull side, just above the waterline near the stern or underwater. Both of those locations allow for the breeze to carry the exhaust away from the boat.
Thirdly, you still have the electrical issues (read below).
Have you checked the condition of your CO monitor, by the way? They do expire.
These, below, are not my words... I had copied them from another forum and pasted here - written by a gentleman much more knowledgeable than me:
------------------------------------------------------------------------------------------------
PORTABLE GENERATORS ON BOATS
Carbon Monoxide
Is simple to grasp, breathe it in a confined space and you don’t wake up. Permanently mounted marine generators have their exhausts plumbed to exit at or very near the waterline and away from closed occupied spaces.
Uncontained Fuel System Vents
The fuel systems on Honda and other portable generators are vented to the atmosphere and their carburetors have a bowl drain that releases fuel inside the generator case. That means where you run it, store it or put it under way will have gasoline fumes released in the area and if the bowl drain leaks, you have raw fuel spilled and an explosive liquid in the compartment with the generator.
Lack of ignition protection on electrical devices
The electrical components on portables are not ignition protected like marine generator electrical components are. This means you could easily have an arc or spark anytime contact opens or closes or whenever something is plugged in or disconnected.
Lack of Continuous Grounding
Portable generators pose an additional shock hazard since the portable is not grounded to the boat or to a shore side ground. Likely not a problem with a drill or power tool, but if you connect it to your boat's AC system, you have essentially disconnected the green wire.
The Honda iU series generators are inverters. An inverter drives both line and neutral so it is possible to have voltage between neutral and ground. With ground bonded the the boat's bonding system, which mean to the water, this means a shock hazard may exist that normally would not. Anyone who ignores all the above risks and insists on using a portable generator should use a very good, sensitive multi-meter to throughly prove out the electrical system. That the reverse polarity light is lit is clear indication of a potential problem.
The USCG governs only boat manufacturers and the manufacturers voluntarily subscribe to ABYC guidelines, so there is no "law" against using portable generators on boats. However, both the USCG and ABYC say using portable generators on boat is a bad idea and regularly caution boaters against it.
In spite of the fact that Honda’s advertising says that boating is a popular use of their generators, They have not addressed the grounding, gas fume and ignition protection issues and those risks do indeed exist.
If you are one of those who jumped on the CO train and the relatively few deaths attributed to CO, you are not fully considering all the risks of using portable generators on a boat. While accidents may be rare, you do substantially increase your risk of becoming a "statistic" when using a portable generator on a boat.......you put your family unnecessarily at risk when you do.
--------------------------
I agree that it's important to be aware of, and manage, your risks. But portable generators DO impose different risks than a properly installed genny. For one, when at anchor, boats will always face into the wind. Putting the genny on the bow means the wind will blow the exhaust toward the cabin, where you are sleeping. The exhaust will find it it's way in through - whether through small cracks in deck hatches or by the "station wagon" effect... down into the cockpit and will then actually go FORWARD through the cabin door. This EXACT scenario HAS happened in real life.
Second, an installed genny will exhaust out in one of two places: through the hull side, just above the waterline near the stern or underwater. Both of those locations allow for the breeze to carry the exhaust away from the boat.
Thirdly, you still have the electrical issues (read below).
Have you checked the condition of your CO monitor, by the way? They do expire.
These, below, are not my words... I had copied them from another forum and pasted here - written by a gentleman much more knowledgeable than me:
------------------------------------------------------------------------------------------------
PORTABLE GENERATORS ON BOATS
Carbon Monoxide
Is simple to grasp, breathe it in a confined space and you don’t wake up. Permanently mounted marine generators have their exhausts plumbed to exit at or very near the waterline and away from closed occupied spaces.
Uncontained Fuel System Vents
The fuel systems on Honda and other portable generators are vented to the atmosphere and their carburetors have a bowl drain that releases fuel inside the generator case. That means where you run it, store it or put it under way will have gasoline fumes released in the area and if the bowl drain leaks, you have raw fuel spilled and an explosive liquid in the compartment with the generator.
Lack of ignition protection on electrical devices
The electrical components on portables are not ignition protected like marine generator electrical components are. This means you could easily have an arc or spark anytime contact opens or closes or whenever something is plugged in or disconnected.
Lack of Continuous Grounding
Portable generators pose an additional shock hazard since the portable is not grounded to the boat or to a shore side ground. Likely not a problem with a drill or power tool, but if you connect it to your boat's AC system, you have essentially disconnected the green wire.
The Honda iU series generators are inverters. An inverter drives both line and neutral so it is possible to have voltage between neutral and ground. With ground bonded the the boat's bonding system, which mean to the water, this means a shock hazard may exist that normally would not. Anyone who ignores all the above risks and insists on using a portable generator should use a very good, sensitive multi-meter to throughly prove out the electrical system. That the reverse polarity light is lit is clear indication of a potential problem.
The USCG governs only boat manufacturers and the manufacturers voluntarily subscribe to ABYC guidelines, so there is no "law" against using portable generators on boats. However, both the USCG and ABYC say using portable generators on boat is a bad idea and regularly caution boaters against it.
In spite of the fact that Honda’s advertising says that boating is a popular use of their generators, They have not addressed the grounding, gas fume and ignition protection issues and those risks do indeed exist.
If you are one of those who jumped on the CO train and the relatively few deaths attributed to CO, you are not fully considering all the risks of using portable generators on a boat. While accidents may be rare, you do substantially increase your risk of becoming a "statistic" when using a portable generator on a boat.......you put your family unnecessarily at risk when you do.
Dennis,
I sincerely appreciate you posting this info. People need to be aware of the risks. Most of them can be minimized or eliminated if one understands the why behind them. If one doesn't, don't use a portable.
I sincerely appreciate you posting this info. People need to be aware of the risks. Most of them can be minimized or eliminated if one understands the why behind them. If one doesn't, don't use a portable.
My plan is to secure this to the hard top and use during the day while underway in the summer, maybe while on the hook but only for the wife if she gets too hot. I have no plans to overnight on the boat unless it’s cold enough to do without needing a generator. Unfortunately I have no place on the boat for a built in generator, nor would I need one enough to install one.
Summertop511
Well-Known Member
I have a 282 also.
I don’t know how many amps your system is pulling but I installed a new dometic 6k btu heat pump last year. Condenser water pump and condensing unit pull roughly 5.5 amps if memory serves correctly.
Last your i bought an OUPES 2000 battery power bank. Plugged it into my shore power and would last a good bit while also charging off cig lighter.
This year I repowered with 2025 f300’s that have a higher amp charging then the 3.3l 250’s that were on it. So I found a bi directional inverter I just installed last night. Going to try it out. Replaced the older battery charger that was on the bought from factory 2008.
Here is a link to the charger / inverter. https://www.solar-electric.com/cotek-sc1200-112-combo-bi-directional-inverter-charger.html
Right now just one house battery but plan is to have a total of three group 31 house batteries for when motors are off and motors themselves should be enough to keep hvac running while motors are running.
Yamaha sells a battery isolater I installed that charges house battery after starting battery is fully charged.
I don’t know how many amps your system is pulling but I installed a new dometic 6k btu heat pump last year. Condenser water pump and condensing unit pull roughly 5.5 amps if memory serves correctly.
Last your i bought an OUPES 2000 battery power bank. Plugged it into my shore power and would last a good bit while also charging off cig lighter.
This year I repowered with 2025 f300’s that have a higher amp charging then the 3.3l 250’s that were on it. So I found a bi directional inverter I just installed last night. Going to try it out. Replaced the older battery charger that was on the bought from factory 2008.
Here is a link to the charger / inverter. https://www.solar-electric.com/cotek-sc1200-112-combo-bi-directional-inverter-charger.html
Right now just one house battery but plan is to have a total of three group 31 house batteries for when motors are off and motors themselves should be enough to keep hvac running while motors are running.
Yamaha sells a battery isolater I installed that charges house battery after starting battery is fully charged.
Hard top while running seems fine, but if on the hook, I recommend transom. On the hook, the boat should sit with the wind (assuming you aren't in a big current) and therefore, the wind will blow from bow to stern and, therefore, the generator will be "downwind." In addition, those fumes sink, so, they would have to go against gravity to go up and over the transom and then against any wind to get to the cabin. As far as power, my 2000 did have enough juice for the ac on my marlin, but it didn't on my 330, not sure if the units were different but that was my experience.
Legend
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My Honda 2000 has a carbon monoxide shut off built in. Honda generators have a carbon monoxide sensor device known as the CO-MINDER.
Source: https://generatorsadvice.com/honda-generator-co-sensor-bypass.
Source: https://generatorsadvice.com/honda-generator-co-sensor-bypass.
Interesting tech. This statement and the diagram that followed don't seem to align:
3. Place the generator such that the muffler faces towards the wind and the exhaust goes in the opposite direction of any nearby buildings or cars.
Also it would seem that the generator would only shut down if operated in an area with high CO. Does this mean that any CO from the generator would dissipate sufficiently if it traveled elsewhere that didn't lead to the generator shutting down? I doubt it. I almost feel this safety feature creates a false sense of security. Maybe it is only intended to save the Darwin Award contestants who operate one of these in the house with no ventilation?
3. Place the generator such that the muffler faces towards the wind and the exhaust goes in the opposite direction of any nearby buildings or cars.
Also it would seem that the generator would only shut down if operated in an area with high CO. Does this mean that any CO from the generator would dissipate sufficiently if it traveled elsewhere that didn't lead to the generator shutting down? I doubt it. I almost feel this safety feature creates a false sense of security. Maybe it is only intended to save the Darwin Award contestants who operate one of these in the house with no ventilation?
kirk a
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I'm skeptical. While it would work for the space the generator occupies, it seems that it offers a false sense of security, as the CO could migrate away from the generator and into the cabin area, for instance. So while the area around the generator has no build up of CO, the cabin could.