Just looking at a new Hunter for doing weekends. The sales guy told me it might be possible to upgrade the alternator and use the onboard engine as a generator for heat and ...... Has anyone heard of this? We are lloking to beable to supplement our power when away from dock for 3-4 days. The boat has Heat but only from shore power presently. Thanks Jason
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Jason, you need to provide more info...
about your situation in order to obtain any meaningful response. What model Yanmar do you have? How many amp hours does the current alternator produce? What kind of heat source do you have on the boat? How many amps does it draw? How many amp hours does your house bank store? Does it have an inverter? Most appliances that use AC to produce heat require more DC than an engine alternator or house bank can sustain for any period. Attempting to use your propulsion engine also as an AC generator, from what I know, seems unwise, IMHO. You can install a higher capacity DC alternator, but there is a limit. Engine horsepower is but one of many factors in determining the size of alternator you choose. If you need an appliance to heat your boat while on the hook for a few days, I recommend a Wallas forced air diesel furnace. It's whisper quiet, sips fuel, and draws very little DC current. As far as the other stuff...you need to define it. Terry
about your situation in order to obtain any meaningful response. What model Yanmar do you have? How many amp hours does the current alternator produce? What kind of heat source do you have on the boat? How many amps does it draw? How many amp hours does your house bank store? Does it have an inverter? Most appliances that use AC to produce heat require more DC than an engine alternator or house bank can sustain for any period. Attempting to use your propulsion engine also as an AC generator, from what I know, seems unwise, IMHO. You can install a higher capacity DC alternator, but there is a limit. Engine horsepower is but one of many factors in determining the size of alternator you choose. If you need an appliance to heat your boat while on the hook for a few days, I recommend a Wallas forced air diesel furnace. It's whisper quiet, sips fuel, and draws very little DC current. As far as the other stuff...you need to define it. Terry
I am assuming that
you want to generate 120 volts AC from your propulsion engine. It can be done, but several things complicate the process. A four pole AC generator must spin at 1800RPM to generate 60 cycles per second(60Hz). In order to maintain this frequency, your engine must run at a constant speed all the time. If you need to slow down or speed up the boat, the AC generator must be shut down or damage can result to anything running on AC power if the frequency changes. Another issue, as electrical load changes, the RPM of the engine will want to change. you need a governor to maintain constant RPM. This setup is not very practical. For cabin heat when the motor isn't running, burn fossil fuel. If your engine uses a fresh water closed loop cooling system, (most do) you can install a heater that uses engine heat just like in your car for heat when the engine is running. For 120 v AC use an inverter, just realise that an inverter will draw over 10 times the amps on a 12 volt system than it supplies on the 120 volt AC side.
you want to generate 120 volts AC from your propulsion engine. It can be done, but several things complicate the process. A four pole AC generator must spin at 1800RPM to generate 60 cycles per second(60Hz). In order to maintain this frequency, your engine must run at a constant speed all the time. If you need to slow down or speed up the boat, the AC generator must be shut down or damage can result to anything running on AC power if the frequency changes. Another issue, as electrical load changes, the RPM of the engine will want to change. you need a governor to maintain constant RPM. This setup is not very practical. For cabin heat when the motor isn't running, burn fossil fuel. If your engine uses a fresh water closed loop cooling system, (most do) you can install a heater that uses engine heat just like in your car for heat when the engine is running. For 120 v AC use an inverter, just realise that an inverter will draw over 10 times the amps on a 12 volt system than it supplies on the 120 volt AC side.
Comfort on the cold days anchored
What we really want to know. what is the best way to keep warm mostly while anchored. As we have have two small kids and a little comfort goes a long way for enjoyment. Its sounds like we will purchase the AC/Heat for when at a marina and we will have to look in to a Diesal heater. Everything just ads up...! the AC heat is $6500from Hunter I have no idea what a diesal heater will cost??
What we really want to know. what is the best way to keep warm mostly while anchored. As we have have two small kids and a little comfort goes a long way for enjoyment. Its sounds like we will purchase the AC/Heat for when at a marina and we will have to look in to a Diesal heater. Everything just ads up...! the AC heat is $6500from Hunter I have no idea what a diesal heater will cost??
That kind of cash will buy a hellava furnace for
your home. How big is your boat. After market AC heaters, even built in, aren't a tenth that expensive. Maybe Hunter thought 'heat-pump' when you asked for a 'AC' quote. The Wallis diesel furnace I installed 3 years ago was over $2200. I thought that was outrageous. But what are you going to do, buy a Espar? No way, made that mistake once.
your home. How big is your boat. After market AC heaters, even built in, aren't a tenth that expensive. Maybe Hunter thought 'heat-pump' when you asked for a 'AC' quote. The Wallis diesel furnace I installed 3 years ago was over $2200. I thought that was outrageous. But what are you going to do, buy a Espar? No way, made that mistake once.
Jason, for boats in the 30 to 40 foot range...
Wallas makes a 30D that can be self installed if you are mechanically inclined for about the price Fred mentioned in his reply. I've been looking at the 40D for our boat. We had the smaller unit (1200 I think) on our H28 and it was a little wonder. It was bulk head mounted, compact and generated about 6,000 BTU. No duct work required (small boat) and it sipped about a half pint of kerosene an hour. I think it was under a grand. Unless you need cold air during the hot summer months, skip the heat pump and go with the furnace. Terry
Wallas makes a 30D that can be self installed if you are mechanically inclined for about the price Fred mentioned in his reply. I've been looking at the 40D for our boat. We had the smaller unit (1200 I think) on our H28 and it was a little wonder. It was bulk head mounted, compact and generated about 6,000 BTU. No duct work required (small boat) and it sipped about a half pint of kerosene an hour. I think it was under a grand. Unless you need cold air during the hot summer months, skip the heat pump and go with the furnace. Terry
Fred, why was Espar a mistake?
I was just looking into the Espar Airtronic 2 or 4 for Hunter 36. They looked like nice units. Also do you know what Hunter use when installing a diesel heater? thanks, abe
I was just looking into the Espar Airtronic 2 or 4 for Hunter 36. They looked like nice units. Also do you know what Hunter use when installing a diesel heater? thanks, abe
Abe, that's a sore subject, even if it's an old
one. I installed an Espar in our Hunter when she was new. (does model # 10D sound right?)It was nothing but trouble the first year. (remember, I'm going back to '86 and later) It seemed every component was failing. After the second season started, it refused to run. After trouble shooting the malfunction, I learned the combustion chamber had rusted out. It was a YEAR OLD!!! I called the company. They said "Sorry, it's out of warranty. Your repair charges for a new combustion chamber is $300.00. (I screamed)! They said, "That's not bad for a year!!!" "That was the cost of a new home furnace!" I said. (It was the 80s) They said 'sorry'. I tried to rebuild it myself with poor results. It kept refusing to run. I gave up and ordered a new combustion chamber when we left the State for Mexico in '91. It lasted down the cost to San Fransisco and quit. We buried it at sea in the Caribbean.
one. I installed an Espar in our Hunter when she was new. (does model # 10D sound right?)It was nothing but trouble the first year. (remember, I'm going back to '86 and later) It seemed every component was failing. After the second season started, it refused to run. After trouble shooting the malfunction, I learned the combustion chamber had rusted out. It was a YEAR OLD!!! I called the company. They said "Sorry, it's out of warranty. Your repair charges for a new combustion chamber is $300.00. (I screamed)! They said, "That's not bad for a year!!!" "That was the cost of a new home furnace!" I said. (It was the 80s) They said 'sorry'. I tried to rebuild it myself with poor results. It kept refusing to run. I gave up and ordered a new combustion chamber when we left the State for Mexico in '91. It lasted down the cost to San Fransisco and quit. We buried it at sea in the Caribbean.
Best Way to Keep Warm While Anchored
Jason - don't know where "Midland" is - but if it's in the northern latitudes I'd recommend one have a concern for humidity. Also, we don't know what kind of boat you're looking at. If it's a small boat then you probably don't want to invest large sums of money in it. However, a cold crew, as you know, will make an unhappy boat. This would be my take: Cheapest way to keep warm: is a bulkhead heater. This is about as cheap as it gets. However, this just heats the air and increases the humidity in the cabin. Minimal electricity required. For weekending - probably a good choice. Best way to keep warm: Forced air heat. It's good in areas with more humidity because it'll help combat mildew. Ductwork is a problem because of it's large diameter. Do not run ducts through structural beams, such as are found in the pans of most boats. If you do, make sure the holes are "blessed" by the boat manufacturer and keep the paperwork for when the boat is surveyed for selling. Forced air heaters like good voltage at startup - this means good (high voltage) batteries and good conductors to avoid damage to the glow plug. This is my admittedly biased preference. Hot water heat, i.e., hydronic systems: have the worst of both worlds. They're expensive (more than a bulkhead heater) and they don't help to combat moisture or mold. Installation requires attention to detail to avoid air locks. Recommend you talk to some boat heater dealers and get their views to compare with what you read here.
Jason - don't know where "Midland" is - but if it's in the northern latitudes I'd recommend one have a concern for humidity. Also, we don't know what kind of boat you're looking at. If it's a small boat then you probably don't want to invest large sums of money in it. However, a cold crew, as you know, will make an unhappy boat. This would be my take: Cheapest way to keep warm: is a bulkhead heater. This is about as cheap as it gets. However, this just heats the air and increases the humidity in the cabin. Minimal electricity required. For weekending - probably a good choice. Best way to keep warm: Forced air heat. It's good in areas with more humidity because it'll help combat mildew. Ductwork is a problem because of it's large diameter. Do not run ducts through structural beams, such as are found in the pans of most boats. If you do, make sure the holes are "blessed" by the boat manufacturer and keep the paperwork for when the boat is surveyed for selling. Forced air heaters like good voltage at startup - this means good (high voltage) batteries and good conductors to avoid damage to the glow plug. This is my admittedly biased preference. Hot water heat, i.e., hydronic systems: have the worst of both worlds. They're expensive (more than a bulkhead heater) and they don't help to combat moisture or mold. Installation requires attention to detail to avoid air locks. Recommend you talk to some boat heater dealers and get their views to compare with what you read here.
Automotive heat
Why can't an engine-supplied heating system like that in a car be installed in a small inboard boat? It would require a water-to-air heat exchanger-- a heater core as in a car. It would require plumbing engine cooling water through it and locating the core with a small 12vdc fan somewhere near the bottom of the companionway ladder. It would provide warm-air heat whenever the engine is running. I think of all those miserably grey days when you are motoring or motorsailing with the dodger up and would love a breath of warm air-- literally. This would fit the bill. For boats fitted with diesel fuel tanks I would seriously look into a Dickinson bulkhead-mount cabin heater (about 500.00). You need to vent it to the cabintop and provide a little 12vdc fuel pump. Demand on the main fuel tank is really minimal and the light diesel scent can actually be heartwarming on an ugly day. JC 2 cherubiniyachts@aol.com
Why can't an engine-supplied heating system like that in a car be installed in a small inboard boat? It would require a water-to-air heat exchanger-- a heater core as in a car. It would require plumbing engine cooling water through it and locating the core with a small 12vdc fan somewhere near the bottom of the companionway ladder. It would provide warm-air heat whenever the engine is running. I think of all those miserably grey days when you are motoring or motorsailing with the dodger up and would love a breath of warm air-- literally. This would fit the bill. For boats fitted with diesel fuel tanks I would seriously look into a Dickinson bulkhead-mount cabin heater (about 500.00). You need to vent it to the cabintop and provide a little 12vdc fuel pump. Demand on the main fuel tank is really minimal and the light diesel scent can actually be heartwarming on an ugly day. JC 2 cherubiniyachts@aol.com
I have a heat exchanger/auto type of heater
It was delivered that way. It just does not work as well as a car heater. Two reasons 1. The boat engine runs at a cooler temperature. 2. The design is extremely poor. Yanmar engines do have a hot water connection for this purpose but it does not work well on my engine (3hm35) and never has. It is supposed to heat the hot water tank too but much of the time it actually cools whatever hot water is in the tank. Running the engine full out for hours gets me a slightly warm heater.
It was delivered that way. It just does not work as well as a car heater. Two reasons 1. The boat engine runs at a cooler temperature. 2. The design is extremely poor. Yanmar engines do have a hot water connection for this purpose but it does not work well on my engine (3hm35) and never has. It is supposed to heat the hot water tank too but much of the time it actually cools whatever hot water is in the tank. Running the engine full out for hours gets me a slightly warm heater.
Patrick,
There is a problem with your system. I sugest you bleed the cooling system to remove all traped air. You should be able to make hot water and warm the cabin form ANY fresh water cooled diesel. Yanmar and most other engines use a 160' thermostat on these engines. Yanmar and others usualy provide two ports to tap for the water heater. You'll need to tap these to go to a heater core. Pat McCartin Inland Marine Diesel Buford, Ga imd_ga@hotmail.com
There is a problem with your system. I sugest you bleed the cooling system to remove all traped air. You should be able to make hot water and warm the cabin form ANY fresh water cooled diesel. Yanmar and most other engines use a 160' thermostat on these engines. Yanmar and others usualy provide two ports to tap for the water heater. You'll need to tap these to go to a heater core. Pat McCartin Inland Marine Diesel Buford, Ga imd_ga@hotmail.com
Bled the system repeatedly,
Checked the thermostat. Then I looked up all of the info on the engine that I could find. I have spent several days over several years trying to get this heater to work and it just will not heat up properly. I have posted the issue before and the same issues of "air in the lines" and "check the thermostat" came up then. I did both - several times. The water coming out of the engine just does not ever get hot enough. It is not a matter of bleeding the system. I have measured the water temperature coming out of the engine and it is not hot even when the engine is. Thermostat is ok. I cannot remember if it is 140 or 160 degrees but I think 160 is what I have. I was at one time advised to restrict the cooling water to the heat exchanger but that seems unwise and I did not do that. My friend has the same problem on his boat. Ford engine and different boat but same problem. If he idles his engine at the dock, his hot water tank gets cold - just like mine. His system will eventually heat the hot water tank but it takes hours of hard running and it does not recover quickly. The outside water temperature is quite cold here - rarely over 50 degrees so that may be a part of the issue. If you guys have any new ideas, I would like to hear them and I will try them but I am not too hopeful. My conclusion at this point is that the design of the engine heating circuit is poor for a cold water climate.
Checked the thermostat. Then I looked up all of the info on the engine that I could find. I have spent several days over several years trying to get this heater to work and it just will not heat up properly. I have posted the issue before and the same issues of "air in the lines" and "check the thermostat" came up then. I did both - several times. The water coming out of the engine just does not ever get hot enough. It is not a matter of bleeding the system. I have measured the water temperature coming out of the engine and it is not hot even when the engine is. Thermostat is ok. I cannot remember if it is 140 or 160 degrees but I think 160 is what I have. I was at one time advised to restrict the cooling water to the heat exchanger but that seems unwise and I did not do that. My friend has the same problem on his boat. Ford engine and different boat but same problem. If he idles his engine at the dock, his hot water tank gets cold - just like mine. His system will eventually heat the hot water tank but it takes hours of hard running and it does not recover quickly. The outside water temperature is quite cold here - rarely over 50 degrees so that may be a part of the issue. If you guys have any new ideas, I would like to hear them and I will try them but I am not too hopeful. My conclusion at this point is that the design of the engine heating circuit is poor for a cold water climate.
Another thought
I wasn't aware the water was so cold there. If you're uncomfortable placing a restrictor on the heat exchanger. Then yo might try partialy closing the seacock to limit flow in to the cooling system. Most auxiliarys are designed with 70+ deg water in mind. It sounds like your cooling system is doing it's job. Pat McCartin Inland Marine Diesel Buford, Ga imd_ga@hotmail.com
I wasn't aware the water was so cold there. If you're uncomfortable placing a restrictor on the heat exchanger. Then yo might try partialy closing the seacock to limit flow in to the cooling system. Most auxiliarys are designed with 70+ deg water in mind. It sounds like your cooling system is doing it's job. Pat McCartin Inland Marine Diesel Buford, Ga imd_ga@hotmail.com
Patrick, in your reply you said you...
checked your thermostat. I would replace it with a new one and keep the old as a spare. Both our 2GM and 4JH heated the water for the hot water tank blistering hot. It could be the wrong type for your engine, or it might appear to work but, for some reason does not. Just another consideration. Terry
checked your thermostat. I would replace it with a new one and keep the old as a spare. Both our 2GM and 4JH heated the water for the hot water tank blistering hot. It could be the wrong type for your engine, or it might appear to work but, for some reason does not. Just another consideration. Terry
Thanks, Terry and Pat
I did replace the thermostat once and checked both in hot water with a digital thermometer. They both worked the same way at the same temperature. Terry, since you are in the same water I am in, that theory is out unless you have done some mods you did not mention. If I run the engine as hard as it will go in the summer it might reach 180 on the gauge but the water out of the engine to the aux heater circuit just is not very hot. It seems like the cooling circuit is too efficient for the aux circuit. I have thought of making a unit which attaches to the main engine circuit which diverts the first and hottest water to the aux circuit by using a pair of thermostats. I guess that is kind of a flow restrictor but I am not comfortable just putting a valve into the main cooling line. Likewise to cutting down on the raw water inlet. Wouldn't that risk the impeller on the raw water pump? Come to think of it, I have sort of done that when the raw water intake got plugged with eel grass. That did not help the hot water either as I recall although I was more concerned about the engine overheating at that particular time. Maybe I need to run some more tests.
I did replace the thermostat once and checked both in hot water with a digital thermometer. They both worked the same way at the same temperature. Terry, since you are in the same water I am in, that theory is out unless you have done some mods you did not mention. If I run the engine as hard as it will go in the summer it might reach 180 on the gauge but the water out of the engine to the aux heater circuit just is not very hot. It seems like the cooling circuit is too efficient for the aux circuit. I have thought of making a unit which attaches to the main engine circuit which diverts the first and hottest water to the aux circuit by using a pair of thermostats. I guess that is kind of a flow restrictor but I am not comfortable just putting a valve into the main cooling line. Likewise to cutting down on the raw water inlet. Wouldn't that risk the impeller on the raw water pump? Come to think of it, I have sort of done that when the raw water intake got plugged with eel grass. That did not help the hot water either as I recall although I was more concerned about the engine overheating at that particular time. Maybe I need to run some more tests.
OK Patrick
It seems no one has brought this up. The hot water heat exchanger has to be plumbed to the fresh water system on the engine; the part with the anti-freeze, not the cold sea water being dumped into the exhaust. Check your shop manual. It points out the right plumbing. Mine shows it. The factory did it. I removed it when new and went to propane, but reinstalled it after our rebuild and it works well.
It seems no one has brought this up. The hot water heat exchanger has to be plumbed to the fresh water system on the engine; the part with the anti-freeze, not the cold sea water being dumped into the exhaust. Check your shop manual. It points out the right plumbing. Mine shows it. The factory did it. I removed it when new and went to propane, but reinstalled it after our rebuild and it works well.
Patrick, Fred may be onto something...
Both the 2GM and 4JH were factory stock and I made no mods. Something in your system appears haywire. Perhaps it is in the heat exchanger plumbing as Fred suggests. The engine should heat the coolant to the thermostat's rating, then allowing coolant to bypass for return. I agree with you. I would not block or restrict the raw water flow to the engine cooling system. Just too risky. Terry P.S. Where do you keep your boat?
Both the 2GM and 4JH were factory stock and I made no mods. Something in your system appears haywire. Perhaps it is in the heat exchanger plumbing as Fred suggests. The engine should heat the coolant to the thermostat's rating, then allowing coolant to bypass for return. I agree with you. I would not block or restrict the raw water flow to the engine cooling system. Just too risky. Terry P.S. Where do you keep your boat?
Fred, it is a factory installation - I think
I have checked the manual and it appears to be plumbed correctly to the fresh water side of the cooling system. The last thing that I checked before giving up on the d#@$ thing was the temperature of the water coming out of the engine and it was warm not hot when the engine was warmed up. I think that explains the whole problem. Never figured out why the hot water outlet of the engine does not get hot. Terry, we keep the boat in the Birch Bay Village marina. It is a private marina located at Birch Point on the north side of Birch Bay. You must own property in the Birch Bay Village development to get moorage but it is worth the investment. Cheap moorage but expensive community dues. Two hours due south on a reach to Echo Bay or Shallow Bay and four hours to Friday Harbor depending on currents.
I have checked the manual and it appears to be plumbed correctly to the fresh water side of the cooling system. The last thing that I checked before giving up on the d#@$ thing was the temperature of the water coming out of the engine and it was warm not hot when the engine was warmed up. I think that explains the whole problem. Never figured out why the hot water outlet of the engine does not get hot. Terry, we keep the boat in the Birch Bay Village marina. It is a private marina located at Birch Point on the north side of Birch Bay. You must own property in the Birch Bay Village development to get moorage but it is worth the investment. Cheap moorage but expensive community dues. Two hours due south on a reach to Echo Bay or Shallow Bay and four hours to Friday Harbor depending on currents.
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