Ted asked about water heaters in his post about generators but didn't get much response to the water heater question. What types of water heaters do some of you use? My recently purchased 37c came with the original water heater removed a long time ago. An A.C water heater won't really do me much good. My boat is on a permanent mooring and when crusing my plans are to live on the hook whenever possible. I plan to install a propane system for cooking and would love to figure out a propane water heating system. That seems to present a lot of ventalation problems. Any of you dealt with that successfully? And how about the heat exchanger systems? How well do they work? (I have a 39 hp Yanmar.) I'm pretty new to the bigger boat cruising thing. My previous boat was a little 23 footer. The only equipment was an ice box, an alcohol cook stove, and an outboard. Any input is appreciated, Morrie
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On demand water heater.
Morrie: There are several on-demand water heaters on the market. They will also use electricity too, so that should be of some concern. You may want to check out what is available from the home supply stores and see if these are adaptable for the boat. If you have propane aboard they should not be too difficult to deal with. The other source for some of these units may be places that deal with solar solutions. Many of these homes would only have DC power for the water heaters too.
Morrie: There are several on-demand water heaters on the market. They will also use electricity too, so that should be of some concern. You may want to check out what is available from the home supply stores and see if these are adaptable for the boat. If you have propane aboard they should not be too difficult to deal with. The other source for some of these units may be places that deal with solar solutions. Many of these homes would only have DC power for the water heaters too.
Water heater.
Can't help much Morrie. My '79 has the original water heater and it seems OK. Since I am mostly at the dock the 110V heater is fine. I have the 2QM20 and it barely moves the temp gauge off the peg(120 degrees). So the water is only lukewarm from running the engine. But we rarely use the onboard water except to wash up or wash the dishes. Seems like extended cruising or a mooring would require propane as you suggest. Maybe the camper type as in the Related Link?
Can't help much Morrie. My '79 has the original water heater and it seems OK. Since I am mostly at the dock the 110V heater is fine. I have the 2QM20 and it barely moves the temp gauge off the peg(120 degrees). So the water is only lukewarm from running the engine. But we rarely use the onboard water except to wash up or wash the dishes. Seems like extended cruising or a mooring would require propane as you suggest. Maybe the camper type as in the Related Link?
A propane water heater is possible.
Most sailboat water heaters uses the engine cooling water to heat the water along with 110 V ac electric heater, which is safer than propane. When in port, they have a 110 V ac heater that uses shore power. You can install an inverter to convert your DC battery power to 110 V ac, but you will have to re-charge your battery. You could install solar panel or a wind generator to re-charge your battery when you are at anchor. Most marine approved water heater from manufacturers such as Raritan, Atlantic Marine, Isotemp, Seward Products, and Allcraft seem to only have the engine heat exchanger and electrical heating element water heaters. Commercial available compact propane or LP gas water heaters are usually designed to be installed on Recreational Vehicles only, they might not meet US Coast Guard installation regulation for sailboats. If you have to have your hot shower, there is one manufacture I’ve found on the web that advertises that their tankless propane water heater is designed for marine use. The company is called Precision Temp Inc., they are located in Cincinnati Ohio. In their specification the tankless water heater uses 12 V dc @ 4 amps and uses 2.55 lbs/hr of propane while producing 2 GPM of hot water. Since this is a tankless water heater system, you must have a pressurized fresh water system. See their installation instruction for boats about ventilation, power, water, and gas hookups. I have not used their product, so I don’t know how well they work. Clink on the link for their web site. Fair Winds and Aloha. Clyde
Most sailboat water heaters uses the engine cooling water to heat the water along with 110 V ac electric heater, which is safer than propane. When in port, they have a 110 V ac heater that uses shore power. You can install an inverter to convert your DC battery power to 110 V ac, but you will have to re-charge your battery. You could install solar panel or a wind generator to re-charge your battery when you are at anchor. Most marine approved water heater from manufacturers such as Raritan, Atlantic Marine, Isotemp, Seward Products, and Allcraft seem to only have the engine heat exchanger and electrical heating element water heaters. Commercial available compact propane or LP gas water heaters are usually designed to be installed on Recreational Vehicles only, they might not meet US Coast Guard installation regulation for sailboats. If you have to have your hot shower, there is one manufacture I’ve found on the web that advertises that their tankless propane water heater is designed for marine use. The company is called Precision Temp Inc., they are located in Cincinnati Ohio. In their specification the tankless water heater uses 12 V dc @ 4 amps and uses 2.55 lbs/hr of propane while producing 2 GPM of hot water. Since this is a tankless water heater system, you must have a pressurized fresh water system. See their installation instruction for boats about ventilation, power, water, and gas hookups. I have not used their product, so I don’t know how well they work. Clink on the link for their web site. Fair Winds and Aloha. Clyde
Espar Heaters are Small and Use Diesel
Take a look at the Espar water heaters. Because of their really small size they would be a good option to consider. The smallest model is a compact L= 9" (23 cm), W= 3.5" (9 cm), H= 6.3" (16 cm) and can put out up to 13,000 BTU, 11,000 BTU continuous, for space heating - that's impressive. Since they burn diesel there wouldn't be a need for a second fuel source.
Take a look at the Espar water heaters. Because of their really small size they would be a good option to consider. The smallest model is a compact L= 9" (23 cm), W= 3.5" (9 cm), H= 6.3" (16 cm) and can put out up to 13,000 BTU, 11,000 BTU continuous, for space heating - that's impressive. Since they burn diesel there wouldn't be a need for a second fuel source.
Heater
We have the 2QM 20 also and 1/2 hour of engine time gives plenty of hot water for two showers and more with a Seaward 6 gallon heater. Many catamarans use the propane tankless hot water heaters. If you want propane check with Precision Yachts who manufacture the Gemini cats. Propane as with any other fuel is as safe as the caution exhibited by the person using it.
We have the 2QM 20 also and 1/2 hour of engine time gives plenty of hot water for two showers and more with a Seaward 6 gallon heater. Many catamarans use the propane tankless hot water heaters. If you want propane check with Precision Yachts who manufacture the Gemini cats. Propane as with any other fuel is as safe as the caution exhibited by the person using it.
Thanks !
Wow! Thanks for the great responses - plenty of choices to investigate. I've got a notion to buy one of the little camp water heaters just to check it out. I've seen a lot of on-demand gas water heaters but could't seen to track one down that was made for the marine environment. Thanks Clyde, I'll be looking into that one. I hadn't thought of diesel before, that looks pretty interesting, too. This sure is a great forum for information sharing! Morrie
Wow! Thanks for the great responses - plenty of choices to investigate. I've got a notion to buy one of the little camp water heaters just to check it out. I've seen a lot of on-demand gas water heaters but could't seen to track one down that was made for the marine environment. Thanks Clyde, I'll be looking into that one. I hadn't thought of diesel before, that looks pretty interesting, too. This sure is a great forum for information sharing! Morrie
Propane water heater
For what it's worth, the PO of our H34 installed a Wolter on-demand propane hot water heater. (I am unable to locate the company.) We love the system. Hot water within seconds, and if this unit ever breaks down, I plan on staying with propane. We also use a Force 10 propane "fireplace" at anchor. Just be aware of the hazards, perform maintenance checks, etc. Our tanks are located in exterior "saddle bags" similiar to the H37 RAINBOW CHASER.
For what it's worth, the PO of our H34 installed a Wolter on-demand propane hot water heater. (I am unable to locate the company.) We love the system. Hot water within seconds, and if this unit ever breaks down, I plan on staying with propane. We also use a Force 10 propane "fireplace" at anchor. Just be aware of the hazards, perform maintenance checks, etc. Our tanks are located in exterior "saddle bags" similiar to the H37 RAINBOW CHASER.
Wolter water heater is now Precision Temp
From a marine web site: "The Wolter water heater was developed in the early 80's by Gerry Wolter. As the story goes Gerry got tired of taking cold showers while sailing, so he started thinking about how to fix this problem. What he came up with was, the prototype to the now Wolter marine water heater. The compact heater worked flawlessly. No more cold Navy showers. The heater worked so well he decided to run a small ad in one of the many sailing magazine. Not surprisingly he started to get inquires about the heater. After a few months of relentless phone calls he decided to take on a partner and streamline his prototype heater and put it into production. The heater was an overwhelming success, over 1200 heaters were sold through out the 80's. Unfortunately in the early 90's the partnership was dissolved and along with Gerry's partner went the rights to the Wolter water heater. Gerry didn't give up though he formed a new company called Precision Temp Inc…" If you have a Wolter hot water heater, it looks like its will be hard to get parts for it. The Espar diesel heater mention by John looks like it is used for cabin heating and not as a hot water heater for personal use. For a hot water heater, you have to be able to limit the water temperature to a specific temperature to prevent scalding. On Espar's web site there were no indications that you could use their diesel heater as a hot water heater to take a shower, they only mention using it for heating the cabin of a sailboat under their application section. Fair Winds and Aloha. Clyde
From a marine web site: "The Wolter water heater was developed in the early 80's by Gerry Wolter. As the story goes Gerry got tired of taking cold showers while sailing, so he started thinking about how to fix this problem. What he came up with was, the prototype to the now Wolter marine water heater. The compact heater worked flawlessly. No more cold Navy showers. The heater worked so well he decided to run a small ad in one of the many sailing magazine. Not surprisingly he started to get inquires about the heater. After a few months of relentless phone calls he decided to take on a partner and streamline his prototype heater and put it into production. The heater was an overwhelming success, over 1200 heaters were sold through out the 80's. Unfortunately in the early 90's the partnership was dissolved and along with Gerry's partner went the rights to the Wolter water heater. Gerry didn't give up though he formed a new company called Precision Temp Inc…" If you have a Wolter hot water heater, it looks like its will be hard to get parts for it. The Espar diesel heater mention by John looks like it is used for cabin heating and not as a hot water heater for personal use. For a hot water heater, you have to be able to limit the water temperature to a specific temperature to prevent scalding. On Espar's web site there were no indications that you could use their diesel heater as a hot water heater to take a shower, they only mention using it for heating the cabin of a sailboat under their application section. Fair Winds and Aloha. Clyde
Espar diesel heater
If you delve deeply into the Espar site you can find the info on using one of their models for a dual purpose (cabin heating and hot water heating). If you select *marine* from the applications section then select the *marine brochure* link that'll get you a PDF file that take forever to load. Morrie
If you delve deeply into the Espar site you can find the info on using one of their models for a dual purpose (cabin heating and hot water heating). If you select *marine* from the applications section then select the *marine brochure* link that'll get you a PDF file that take forever to load. Morrie
I thought you had no hot water tank??
I must have been unclear in my previous response. I should have stated that the Epsar diesel coolant heater can not be used as a tankless hot water heater to heat water for domestic use such as showering or washing dishes, since it does not have the necessary over temperature protection to prevent scalding. You can get the Epsar diesel coolant heater in either air or water output units. If you read the “Marine” brochure it shows you must connect the hot water output of the Epsar to an already existing hot water system with a marine approved hot water tank. The hot water tank has the over temperature cutoff and the pressure relief valve to make it US Coast Guard approved for marine use. Most marine hot water tanks are sold as hot water heaters with electric heating elements and internal pipes that are connected to the boat’s engine coolant system to act as a heat exchanger. You can also get the hot water heaters with the electric elements only, I don’t know if you can get them with only the heat exchanger and without the electric elements. All the Epsar diesel coolant heater does is replace the connection to your engine’s coolant system to the hot water heater. You must get a marine approved hot water tank with the temperature cutoff and pressure relief valve if you want to use the Epsar instead of your sailboat's engine. Fair Winds and Aloha. Clyde
I must have been unclear in my previous response. I should have stated that the Epsar diesel coolant heater can not be used as a tankless hot water heater to heat water for domestic use such as showering or washing dishes, since it does not have the necessary over temperature protection to prevent scalding. You can get the Epsar diesel coolant heater in either air or water output units. If you read the “Marine” brochure it shows you must connect the hot water output of the Epsar to an already existing hot water system with a marine approved hot water tank. The hot water tank has the over temperature cutoff and the pressure relief valve to make it US Coast Guard approved for marine use. Most marine hot water tanks are sold as hot water heaters with electric heating elements and internal pipes that are connected to the boat’s engine coolant system to act as a heat exchanger. You can also get the hot water heaters with the electric elements only, I don’t know if you can get them with only the heat exchanger and without the electric elements. All the Epsar diesel coolant heater does is replace the connection to your engine’s coolant system to the hot water heater. You must get a marine approved hot water tank with the temperature cutoff and pressure relief valve if you want to use the Epsar instead of your sailboat's engine. Fair Winds and Aloha. Clyde
OK, I see
Clyde, I saw the part on the Espar site that said it may be used for "domestic use," etc. and I thought I wasn't completely understanding how it worked. What I didn't understand was the part about needing an existing water heater for the thermostat and pressure relief functions. Thanks for taking the time to make that clear. It did sound kind of too good to be true, cabin heat and hot water in one tiny unit. I've read up on a number of different heat exchanger/110 volt units but I'm really thinking, at this point, I'm going to go with the Precision Temp propane unit, especially after reading what Bobby and Kathy said about their Wolter. Thanks again all, Aloha, Morrie
Clyde, I saw the part on the Espar site that said it may be used for "domestic use," etc. and I thought I wasn't completely understanding how it worked. What I didn't understand was the part about needing an existing water heater for the thermostat and pressure relief functions. Thanks for taking the time to make that clear. It did sound kind of too good to be true, cabin heat and hot water in one tiny unit. I've read up on a number of different heat exchanger/110 volt units but I'm really thinking, at this point, I'm going to go with the Precision Temp propane unit, especially after reading what Bobby and Kathy said about their Wolter. Thanks again all, Aloha, Morrie
Paloma or Bosch are cheaper
After doing a lot of research on this subject, comparing the options available, I came to the conclusion that, although the Precision Temp system is a dandy set-up, the Bosch or Paloma heaters offer essentially the same performance at approximately one - third the cost. All systems require outside venting, and all will have the inevitable addition of water vapour to the interior of the vessel(a result of propane burning). Bosch seems to hold the edge in reliability / dollar spent. Hope this helps.
After doing a lot of research on this subject, comparing the options available, I came to the conclusion that, although the Precision Temp system is a dandy set-up, the Bosch or Paloma heaters offer essentially the same performance at approximately one - third the cost. All systems require outside venting, and all will have the inevitable addition of water vapour to the interior of the vessel(a result of propane burning). Bosch seems to hold the edge in reliability / dollar spent. Hope this helps.
Instant (Flash) Hot Water
Having experienced your almost exact needs and requirements, as well as the same boat, I hereby offer my solution which has served us very well for the past two years "out here" on the hook and at moorings. We haven't seen a slip since Dec., 2000. The Bosch unit is very reliable, comparatively cheap, and works on its lowest setting to give us comfortable showers and clean dishes. It is vented to the cabin top directly above, and is supplied with propane from tanks lashed to the base of the mast, through a solenoid valve. I will attempt to attach a photo so you can see the unit in the shower compartment of our 37-c.
Having experienced your almost exact needs and requirements, as well as the same boat, I hereby offer my solution which has served us very well for the past two years "out here" on the hook and at moorings. We haven't seen a slip since Dec., 2000. The Bosch unit is very reliable, comparatively cheap, and works on its lowest setting to give us comfortable showers and clean dishes. It is vented to the cabin top directly above, and is supplied with propane from tanks lashed to the base of the mast, through a solenoid valve. I will attempt to attach a photo so you can see the unit in the shower compartment of our 37-c.
Attachments
Which model?
Dave, Which model Bosch do you have? Does it have a flame pilot or a 12 volt spark ignition of some kind. And what kind of vent cap do you use? Thanks, Morrie
Dave, Which model Bosch do you have? Does it have a flame pilot or a 12 volt spark ignition of some kind. And what kind of vent cap do you use? Thanks, Morrie
Particulars......
Morrie..... The heater is an Aqua-Star 38-B by Bosch (I think Bosch bought Aqua-Star and their technology). It has a piezo-electric igniter that lights a pilot flame. When we want hot water, we first have to light the pilot after turning on the solenoid. I got it from Jade Mountain (now RealGoods.com), one of the sustainable energy websites. The stovepipe you see leading upward goes as far amidships as possible, then turns directly upward through the cabintop and ends in a cheap, Home Depot aluminum doeuble-wall chimney top. The stainless Charley Noble is just too pricey for us, as is the SS double-wall flex pipe. We just used aluminum flex as well.
Morrie..... The heater is an Aqua-Star 38-B by Bosch (I think Bosch bought Aqua-Star and their technology). It has a piezo-electric igniter that lights a pilot flame. When we want hot water, we first have to light the pilot after turning on the solenoid. I got it from Jade Mountain (now RealGoods.com), one of the sustainable energy websites. The stovepipe you see leading upward goes as far amidships as possible, then turns directly upward through the cabintop and ends in a cheap, Home Depot aluminum doeuble-wall chimney top. The stainless Charley Noble is just too pricey for us, as is the SS double-wall flex pipe. We just used aluminum flex as well.
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