Heating options

[GILow]

Scaling should not be a problem with a closed loop system. Just treat the water with conventional corrosion inhibitors and change the coolant every few years.

[Pizzazz]

I have one more specific question on bulkhead heaters. I understand that Dickenson heaters are fully sealed, so they draw outside air, combust it with either diesel or propane, then exhaust it. This is the best o e can do on a boat.

However, there the other type open air heaters that take cabin air, combust it, then exhaust cia the flue. Examples would be the Cabin Cozy Heater, the good old wood stove and then an alcohol heater with an exhaust flue. These heaters spill some of the hot air/vapor in the cabin which contributes to the humidity (or at least that is my understanding).

The alcohol heaters have one slight advantage, since there is O atom in alcohol, it adds a little bit of oxygen from the fuel, so they deplete oxygen from the cabin slightly slower. They have a number of disadvantages such as lower energy content vs. diesel and lack of availability of pure, 95% proof ethanol. So, we usually get some additives that smell bad and also may be cancerogenic.

Question is, what is the principal difference between an unsealed propane heater (Cozy Cabin) and an Original stove burner with a flame enclosure and a chimney that exits the boat? To me they seem equivalent. The next question is why there aren't vented alcohol heaters for sale? Am I missing something? It would be the easiest solution to add a vented ss enclosure to my Original stove.

[newhaul]

Originally Posted by Pizzazz

I have one more specific question on bulkhead heaters. I understand that Dickenson heaters are fully sealed, so they draw outside air, combust it with either diesel or propane, then exhaust it. This is the best o e can do on a boat.

However, there the other type open air heaters that take cabin air, combust it, then exhaust cia the flue. Examples would be the Cabin Cozy Heater, the good old wood stove and then an alcohol heater with an exhaust flue. These heaters spill some of the hot air/vapor in the cabin which contributes to the humidity (or at least that is my understanding).

The alcohol heaters have one slight advantage, since there is O atom in alcohol, it adds a little bit of oxygen from the fuel, so they deplete oxygen from the cabin slightly slower. They have a number of disadvantages such as lower energy content vs. diesel and lack of availability of pure, 95% proof ethanol. So, we usually get some additives that smell bad and also may be cancerogenic.

Question is, what is the principal difference between an unsealed propane heater (Cozy Cabin) and an Original stove burner with a flame enclosure and a chimney that exits the boat? To me they seem equivalent. The next question is why there aren't vented alcohol heaters for sale? Am I missing something? It would be the easiest solution to add a vented ss enclosure to my Original stove.

Actually when alcohol stoves or heaters are properly burning the alcohol there is minimal CO produced and more so CO2 . cracked portlight or deck hatch will be fine .no need for actual exhaust on an alcohol heater.

[VanIslandGuy]

Originally Posted by UNCIVILIZED

For those with hydronic heating, what do you need to do/pay attention to in terms of the water that you use so as to prevent scaling in the plumbing, & heating elements? Since in most boilers I've been around this is fairly critical. And I'd think that it would be even more so on sailboat sized units with small diameter lines.
Also, do you insulate your heating water lines? And how do you run them so as to prevent them from being accidentally dinged?

https://peakauto.com/products/antifreeze-coolants/automotive/sierra/

I use Peak Sierra antifreeze not water in my lines to prevent any corrosion issues. I insulated as most of my lines with simple hose insulation purchased at home depot. The only area I didn't insulate was below the floor boards in the galley as I like that it warms the floor there slightly and it is only a small area so minimal system loss of heat. The insulation works really well and is very inexpensive.

As for running the lines, tape the ends you are pushing through so no contaminate can get in them. Lines run from one bus heater to the next, as well as the hot water tank and back. The worst run we had was from the aft cabin, through the engine room, into the main cabin. Most times you are dealing with 6-10 feet of hose run max from one bus heater to the next.

I would say figure out how many bus heaters you want and where, and the hose layout will become much easier to determine.

[UNCIVILIZED]

Part of the issue with hydronic heaters that I'm inquiring after is that many folks want to use the hot water in the heating system both to heat the boat, as well as for showers, & washing dishes, etc. And if you do this then it means you'll be refilling the system pretty regularly. Which if you're using anything but steam distilled, or RO mfd. water, you'll be adding a lot of minerals & chemicals to the system. As tap water/marina water is anything but pure. So that when boiled, or heated sufficiently, it produces scaling.

[deblen]

Originally Posted by john61ct

by "bus" do you mean as in school bus, or something else?

For those who stay in one cold spot without wanting to run the engine

Webasto and Espar maybe the Russian one too, make active diesel-burning heaters that work that way with hydronic exchangers (calorifiers), radiators etc to move heat around longer distances.

Some are designed to integrate with the engine cooling system, but to heat up the block to assist starting in very cold weather.

Also lets you use any existing integral heating systems, vents and fans etc designed to work when the engine is running, presumably as is meant by "bus heater" above

Commonly called "bus heaters",these hydronic heaters are similar to an auto heater-just an enclosed small radiator & attached fan.
They work fine while under engine power but are no help when engine is stopped. https://shop.hamiltonmarine.com/depa...s-|HT|BHR.html

Len

[GILow]

Originally Posted by UNCIVILIZED

Part of the issue with hydronic heaters that I'm inquiring after is that many folks want to use the hot water in the heating system both to heat the boat, as well as for showers, & washing dishes, etc. And if you do this then it means you'll be refilling the system pretty regularly. Which if you're using anything but steam distilled, or RO mfd. water, you'll be adding a lot of minerals & chemicals to the system. As tap water/marina water is anything but pure. So that when boiled, or heated sufficiently, it produces scaling.

That's not the way to do it. You need a heat exchanger to get hot water from these systems. You can not, and should not, use untreated (corrosion inhibited) water in the furnace or it will rust out in no time at all. Typhoon had an excellent setup but just last night my good mate who is a refrigeration engineer improved on Typhoon's design. I am building the courage to let Typhoon know he has been gazzumped.

[Dockhead]

Originally Posted by UNCIVILIZED

For those with hydronic heating, what do you need to do/pay attention to in terms of the water that you use so as to prevent scaling in the plumbing, & heating elements? Since in most boilers I've been around this is fairly critical. And I'd think that it would be even more so on sailboat sized units with small diameter lines.
Also, do you insulate your heating water lines? And how do you run them so as to prevent them from being accidentally dinged?

Use a 50/50 mixture of distilled water and ethylene glycol - same as in engine fresh water cooling systems.

Yes, the lines need to be well insulated. In my boat, piping and insulation all PEX, like you'd use in a house. The system was part of the original build of my boat. Works great.

[Dockhead]

Originally Posted by UNCIVILIZED

Part of the issue with hydronic heaters that I'm inquiring after is that many folks want to use the hot water in the heating system both to heat the boat, as well as for showers, & washing dishes, etc. And if you do this then it means you'll be refilling the system pretty regularly. Which if you're using anything but steam distilled, or RO mfd. water, you'll be adding a lot of minerals & chemicals to the system. As tap water/marina water is anything but pure. So that when boiled, or heated sufficiently, it produces scaling.

I've never seen anyone do that. These are closed loop systems and shouldnt be used that way. For domestic hot water, you need a calorifier or plate type heat exchanger.

[UNCIVILIZED]

Originally Posted by Dockhead

I've never seen anyone do that. These are closed loop systems and shouldnt be used that way. For domestic hot water, you need a calorifier or plate type heat exchanger.

Right. I well understand this, all too well. Having spent lots of time on US Navy ships with boilers, & steam propulsion plants. Where keeping the chemistry of the water in the system perfect was incredibly important.

However, a lot of folks don't necessarily understand what Dockhead & others have clarified about these systems, above. And they get to thinking that a hydronic heating system can do double duty, both as a heating system, & one for heating water for showers & dishes. Which obviously isn't the case.

Thus I brought up the topic so that no one buys a heating system for their boat based on the thinking that it'll do double duty as a heater, & also for warming up water for showers. At least not without some additional plumbing & hardware.

Dockhead, if you'll recall, you & I had a conversation about keeping the water in one's hydronic heating system within manufacturer's spec's a year or two ago. As anything that has a boiler as part of it's system requires such TLC.

[GILow]

Originally Posted by UNCIVILIZED

Right. I well understand this, all too well. Having spent lots of time on US Navy ships with boilers, & steam propulsion plants. Where keeping the chemistry of the water in the system perfect was incredibly important.

However, a lot of folks don't necessarily understand what Dockhead & others have clarified about these systems, above. And they get to thinking that a hydronic heating system can do double duty, both as a heating system, & one for heating water for showers & dishes. Which obviously isn't the case.

Thus I brought up the topic so that no one buys a heating system for their boat based on the thinking that it'll do double duty as a heater, & also for warming up water for showers. At least not without some additional plumbing & hardware.

Dockhead, if you'll recall, you & I had a conversation about keeping the water in one's hydronic heating system within manufacturer's spec's a year or two ago. As anything that has a boiler as part of it's system requires such TLC.

With respect, anyone buying such a system from a reputable dealer will have this spelled out clearly, and anyone contemplating building their own system would SURELY do the simple research required to understand the basics of such a setup?

Surely...?

OK, maybe not....

Sigh.

[Viking Sailor]

Can someone offer advice on which one of these systems will work best on a sailboat healed over and pounding to windward in a bumpy seaway? Thanks...

[newhaul]

Originally Posted by Viking Sailor

Can someone offer advice on which one of these systems will work best on a sailboat healed over and pounding to windward in a bumpy seaway? Thanks...

IMO the better systems for the scenario you propose would be either forced air diesel furnaces or diesel fired hydronic system's. Vice that I would recommend closed loop diesel or propane fired bulkhead mounted systems.

[Dockhead]

Originally Posted by Viking Sailor

Can someone offer advice on which one of these systems will work best on a sailboat healed over and pounding to windward in a bumpy seaway? Thanks...

Any of the truck type heaters -- hydronic or forced air -- will work fine like that.

[lonesoldier0408]

What's the surface temperature of your solar panels? Tubing attached to the back of the panels, insulated and enclosed. Fluid pumped to insulated tank containing water and thermal mass.