Generators - kW needed for 40 to 45 foot Hunter

[Paula]

Looking at a 43 hunter that does not currently have a generator. Broker said previous owner removed it after it 'crapped out'. Story given to us - It was 6kW and it was not running at peak efficiency, was too large for boat, and wore it out. When it died he removed it. It was a Northern Lights.
Love this boat, but with out a generator, seems we loose a lot of use of the 'extras' on board. Broker said to just get a slip and plug it in, but the idea of a boat this size is to be able to be on the hook, yet be able to use the creature comforts. Are we being told a tall story, or is 6kW too large for this size boat. Seems to be the standard that Hunter installed for the 43.What would the proper size be?
Is Northern lights one that has issues, as I see newer models are sporting the Panda? To buy one to put back in adds a lot of cost to t he boat, and puts her cost above newer models.

 

[uncledom]

There is a lot of info on this topic. My Hunter 41 came with a dealer installed NextGen. Many dealers use Panda. I would opt for a Northern Light. One of the base ideas is wear time. For every min of use a generator comes closer to end of life. Either rebuild or replace. So one theory is it comes down to piston wear. The Fischer Panda runs at 3600 RPM, the NextGen at 2600 RPM and the Northern Lights at 1800 RPM. So the Northern Lights should last the longest physically. Just one thought.

 

[RWSlater]

I have a Hunter 45CC with a Panda 8KW and love it. VERY Quiet and can power everything I need. Just my 2¢

 

[Don S/V ILLusion]

Curious what it is you would lose - "we loose a lot of use of the 'extras' on board."

I can't think of much other than A/C which would necessitate a genset. We rarely use a genset except to moderate the heat in summer here. We have both a refrig and freezer, coffee maker, microwave, my wife's blow dryer(s), entertainment stuff, inverters, etc... and never bother to run the genset except for A/C.

Frankly, if I could get away from a genset, I'd be much happier to eliminate the beast.

 

[Gunni]

The reason 6KW is a sweet spot for gensets on a boat this size is that gives you the 50 amp service you need to power up your entire AC electric side. Typically A/C units on one leg, and your other house stuff on the other. With genset running you have the same power as if you were on shore power.
I share Don's sentiments every year when I have to flush and winterize the genset. Then each spring when she needs a new impeller, filters, oil changes, zincs etc. The previous owner installed it, not something that was important to me. Basically just another engine to care for. But it is satisfying not to have to run my auxiliary just to charge my batteries. However, with the new high-output solar panels there are better options. We sailed the Chesapeake for decades without A/C. Not sure I could justify the cost/benefit.

 

[Bill Roosa]

you need to do a load analysis. Make a list of all the things that you want to run on AC while on the hook. assess the likelyhood of which ones will be on at the same time. Size your genset for the largest set of loads you run at the same time. Some things to consider, do you really want to charge your batteries up to 100% SOC by running the genset all night long? Can you get the "extras" using 12 volts and engine alternator/solar/wind/hydro? If all you are really doing is running the air conditioning consider using 12 volt fans and sun screens for the cabin. My sun screen lowered the cabin temp from 90 to 80 F, even more with temps above 90.
For the record a week+ of sailing will acclimate you to higher temps and humidity and you will not need the air conditioning as much. That is not much help if you are a weekend sailor though but does factor in on long trips.

 

[Jerry Clark H356 SV Persi]

I have a Northern Lights 5KW on my Hunter 356. We start the generator before unplugging from the dock and turn it off when we return. We use our boat while sailing/cruising just as we would sitting at the dock. We keep comfortable and my wife spends as much time below as in the cockpit. We sail on Kentucky Lake from early March thru early December and have extremes from low 20's to mid 90's. For about 6 months a year, we have a full enclosure for the cockpit, for the other 3 months, we take the rear panels off and have a traditional dodger and bimini setup. We are winterized 3 months. We stay comfortable and dry in the cockpit and the saloon, bedroom and head is humidity controlled. We have run ours continuously on a cruise from Tennessee to Florida for as long as 99 hours between marina's. We have about 65 decibels in the cockpit and less inside. It is a noticeable hum but after a while it is background sound. Our airflow from the HVAC is more annoying. At anchor we don't bother anybody. Our exhaust is underwater and 10 feet from our boat you can't hear it running.

There are two schools of thought on a generator. One is like us, treat your boat like a condo using all the conveniences of home and sail it. The other school is go more minimalistic and use the generator to only recharge batteries and maybe use the HVAC to cool the boat for an hour or so before going to bed. Differences of lifestyle, each just as acceptable as the other. Personal choice.

We have the same system components the 430 does plus satellite TV with a KVH antenna, but you have 2 HVAC units if I remember the H430. Each HVAC unit at startup pulls about 1.8 KW. That would mean you need 3.8 KW just for that plus whatever your other loads are. On the dock with metered power, we use just over 1 KW per hour for everything 25.5 KW per day with the diversity of load. You are only using 1.8 KW per HVAC (3.6KW) for the short time it is starting and about 1.3 KW (2.6 KW) while the compressor is running so add your Hot Water heater (1.8 KW) when heating (will be 0 when motoring) microwave (.8 KW) , TV TV antenna and Dish box (.7 KW) outlet loads for computer, IPads, IPhones (.25KW) and other loads (.5 KW) and your peak is again around 6 KW. You want the generator to carry what you are running so I think Hunter sized it right at 6 KW. The Northern lights is 3 cylinders and runs at 1800 RPM which has less vibration and runs quieter and wears less. It was probably not maintained and that is why it wore out. Properly maintained it should last 10,000 hours or more. I have 3146 hours on mine in 15 seasons of use, 1017 days on board total. I'll quit sailing way before my Northern Lights will bite the dust as I turn 70 this season. It is a very heavy duty unit and I burn an average of .25 gallons per hour, about 6 gallons in 24 hours. I maintain it well but other than oil changes and impellers the only other maintenance I've done is injector service at 2684 hours plus 3 belts. Just keep the oil topped off and it should last 10,000 hours or more.

 

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[Terry Cox]

Hi Paula, our 1991 P42 (same hull as the H43) came equipped with an Onan 8kw Genset. The main reason was to provide enough amperes to operate the two reverse cycle heat pumps (16K BTU main cabin, 9K BTU aft cabin) along with all the other power demands of the boat while away from shore power.

During the cruising season we prefer spending time on the hook in some remote anchorage as opposed to a marina. PNW weather does not require the use of heat pumps, but the Genset does come in handy to keep our house bank up. Our routine includes running the Genset every other day for about 1.5 hours, which is sufficient to heat water for washing and bringing the house bank back up to snuff. Our Wallas diesel furnace provides heat if we need it during the off season.

As mentioned in another post, it depends upon your power requirements and cruising style the Genset size for your boating needs. I'm glad that we have ours; it comes in real handy.

 

[Sergey Vetrov]

I have a Northern Lights 5KW on my Hunter 356. We start the generator before unplugging from the dock and turn it off when we return. We use our boat while sailing/cruising just as we would sitting at the dock. We keep comfortable and my wife spends as much time below as in the cockpit. We sail on Kentucky Lake from early March thru early December and have extremes from low 20's to mid 90's. For about 6 months a year, we have a full enclosure for the cockpit, for the other 3 months, we take the rear panels off and have a traditional dodger and bimini setup. We are winterized 3 months. We stay comfortable and dry in the cockpit and the saloon, bedroom and head is humidity controlled. We have run ours continuously on a cruise from Tennessee to Florida for as long as 99 hours between marina's. We have about 65 decibels in the cockpit and less inside. It is a noticeable hum but after a while it is background sound. Our airflow from the HVAC is more annoying. At anchor we don't bother anybody. Our exhaust is underwater and 10 feet from our boat you can't hear it running.

There are two schools of thought on a generator. One is like us, treat your boat like a condo using all the conveniences of home and sail it. The other school is go more minimalistic and use the generator to only recharge batteries and maybe use the HVAC to cool the boat for an hour or so before going to bed. Differences of lifestyle, each just as acceptable as the other. Personal choice.

We have the same system components the 430 does plus satellite TV with a KVH antenna, but you have 2 HVAC units if I remember the H430. Each HVAC unit at startup pulls about 1.8 KW. That would mean you need 3.8 KW just for that plus whatever your other loads are. On the dock with metered power, we use just over 1 KW per hour for everything 25.5 KW per day with the diversity of load. You are only using 1.8 KW per HVAC (3.6KW) for the short time it is starting and about 1.3 KW (2.6 KW) while the compressor is running so add your Hot Water heater (1.8 KW) when heating (will be 0 when motoring) microwave (.8 KW) , TV TV antenna and Dish box (.7 KW) outlet loads for computer, IPads, IPhones (.25KW) and other loads (.5 KW) and your peak is again around 6 KW. You want the generator to carry what you are running so I think Hunter sized it right at 6 KW. The Northern lights is 3 cylinders and runs at 1800 RPM which has less vibration and runs quieter and wears less. It was probably not maintained and that is why it wore out. Properly maintained it should last 10,000 hours or more. I have 3146 hours on mine in 15 seasons of use, 1017 days on board total. I'll quit sailing way before my Northern Lights will bite the dust as I turn 70 this season. It is a very heavy duty unit and I burn an average of .25 gallons per hour, about 6 gallons in 24 hours. I maintain it well but other than oil changes and impellers the only other maintenance I've done is injector service at 2684 hours plus 3 belts. Just keep the oil topped off and it should last 10,000 hours or more.

Hi Jerry
Thank you for your post with ALL details. I am coming close to Genset decision for my H38. Thinking about smallest one as possible (3kW max) to keep less noise, diesel consumption and $$$ of course. Do you have any details about your Genset installation - location / intake / exhaust, etc.
Thank you in advance
Sergey

 

[Rick486]

Hi Jerry
Thank you for your post with ALL details. I am coming close to Genset decision for my H38. Thinking about smallest one as possible (3kW max) to keep less noise, diesel consumption and $$$ of course. Do you have any details about your Genset installation - location / intake / exhaust, etc.
Thank you in advance
Sergey

Be sure to investigate not only the rated/advertised output, but also the max continuous output. We have a Panda 6kw on our 44DS but F-P recommends max continuous at 85%. We run 2 AC, charger, video, etc. no problem. 3 KW sounds a bit small to me.

 

[Sergey Vetrov]

I do not have AC's on my boat (NZ weather is not TOO HOT). I need it to run few appliances (including good coffee machine!) and in future will do water maker AC motor driven. Thank you for advice - need to check watermakers spec...
Cheers

 

[Malcolm/Trilogy]

I have a Passage 42 and kept renovating my 9kva (no sound hood) for 18 years and then replaced it with a new Kohler 5.5kva with sound hood - runs quietly and runs air con and appears much more able to cope than the previous one mavb

 

[seadaddler]

I have a 4200 Fisher Panda on my 2007 H-36 and mostly use it for AC here in Florida,during
our crusing with our sailing club we usually out for about 3 weeks 2 times a year and many other
weekends all mostly on the hook and that is when we would use the Gen.
I also installed 2-195 watt solar panels and with the solar I do use the Gen a lot less and do have a 2000 watt inverter/ charger with 4-6volt house bank and start battery.
The biggest best option was when I added the solar that does most of the battery charging even when at a dock.
Nick

 

[Sergey Vetrov]

Thank you Nick
I have installed 1 X 150W Panel last year - absolutely love it. It gives me plenty of power to keep House and starter batteries in top condition while in Marina. But when I am sailing usually my fridge will suck house battery down to 11.2v during night time so have to use motor for about 1 hour to keep it healthy (until sun is up!). I am planning to put min second one on the top...

 

[SG]

Paula,

If you use the boat in the summer in the Chesapeake while away from the dock, or in the early spring when you 'd like to warm the boat up a little or latter in the fall -- I think you'll like the generator.

If the you can get a constant RPM, conventional generator -- simple, easy to operate, etc. and you can afford it, then it's pretty neat. 6 KW is probably okay.

You have two AC units on the Hunter? Plus a hot water heater? Plus a 130 Amp charger? Find-out what fits AND has some soundproofing. Our engine room is pretty well surrounded by Sounddown; however, we added a framed cover, with removable panels (for servicing). It's not silent, but then if you have a AC going, it's not a big deal. We seldom sleep with the unit running all night -- unless it's one of several miserable nights a year when things don't cool down in late July or August.

A constant velocity (1800 RPM) unit is probably the most reliable. You aren't going to hurt anything if you just keep regular service on the engine (oil, filters, occasional impellers, etc.). The toughest issue is the impellers that get nettles sucked-up into the strainers. If you're north of the Bay Bridge, that's not an issue. South of the Bridge into July and August, you have the nettles, you have the heat. Get ready to change impellers occasionally. ;^))) No big deal, just a pain.

 

[JamesG161]

My H430 has a OEM Kohler 9KW with 1380 hours and runs great.
It handles all running...
1) 100Ahr DC Inverter/Charger [1.5 hour to charge 400 Ahr house batts]
1) 24K BTU for combined heat pump AC's
2) Microwave
3) 2 Big Screen LCD TV's
4) Refrig/Freezer
5) 8 - 120VAC outlets [normally small usage]
_______
My generator is under the forward cabin berth.

Most Large Hunters came with a "spot" for a genset. If the old one "crapped out" then perhaps the AC wiring is still there. If so...

Check the AC wiring size and length to your AC control panel.

IMHO that is the "Pain" of most installations and determines your KW limits.

Other considerations....
1) Mine shares the engine start battery and has an Alternator Isolator, if both engine and genset are running
2) DC starting wires size and Battery location.
3) Ease of Maintenance Access
4) Old Sea Water intake size
5) Exhaust port size
6) Engine Air intake source
7) Engine noise reduction and Heat generation.

Jim...

PS: The Original Owner launched her at Annapolis April 1999 and told the dealer "Deluxe Please"

 

[Jerry Clark H356 SV Persi]

Sergei: My Northern Lights 5KW is in my stern port lazarette. It s enclosed in a soft custom sound shield. Raw water intake is ganged with my other thru hulls at the base of the companionway stairs. It exhausts to the stern with an underwater muffler. Raw water is exhausted out the port side just above the water line. I get about 65 decibles sound from it in the cockpit. Ten to 15 feet away from boat, you can only hear the raw water splashing. It is a slight hum inside and does go away after a while. It s not annoying. It’s sort of equivalent to running the air continuously on the HVAC which we do.

 

[DayDreamer41]

We have the Hunter 41 DS and it did come equipped with a Panda 6.5 KW gen set. Something I have learned from others with gens onboard is just because you don't have a need for them you must run them regularly and when you run them you must put a load on them. As for how it serves the boat, it has been pointed out, it is sized to provide the same amperage as you could get from plugging in both lines at a dock. Our boat has a total of 21 (12+9) K of AC/Heat, water heater and charger if I total all the loads it would be about 80% of the genset capacity.

 

[ice breaker]

Daydreamer:

Was your panda problem solved with a new relay?