I am looking at putting in an Espar D2 Airtronic (or Webasto equivalent). I would be interested to hear from anyone who has done this themselves, to understand just how difficult it is. Or maybe you had someone install but watched it being done.....?
Espar D2/D4 Airtronic Heating: Self Install?
- Thread starter Aquabelle
- Start date
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bobofthenorth
Guru
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- Gray Hawk
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- Defever 43 Offshore Cruiser
I replaced a D7 Espar with a Webasto shortly after we bought Gray Hawk. That was a pretty trivial task. Starting from scratch would be a bit more complex but the only thing I could see that would be at all difficult is the exhaust. If you are replacing an existing forced air heater then its going to be dead simple. On the other hand, if you are starting from scratch I can't imagine why you would go with forced air anyway - hydronic would be way simpler and much more flexible.
psneeld
Guru
Not necessarily simpler and hydronic can be 2-3 times the cost...and actually the exhaust on modern forced air is pretty simple..many times it's just PVC...I've been studying it thoroughly for over a year now for my 40 footer tri-cabin.
bobofthenorth
Guru
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True zone heating, run 1/2" lines instead of 6" plenums, heat your hot water at the same time. It doesn't take much study to see which system is more flexible. The only advantage for forced air is that you get some air exchange which should reduce condensation. I haven't done the research so I could be wrong but in a start from scratch situation I don't see why hydronic would be any more costly - probably less in fact.
psneeld
Guru
never said it was "better"...just refuting your implication that it was simpler (depends on boat). Finding places in a stateroom for baseboard or heat exchangers can be a daunting task on some boats...like mine.
I'm heavily leaning towards the Hurricane... but at $7000 (Kobala boiler system same or even more)versus a little over $2000 for forced air...and a boat I plan on taking south each winter...hmmmm....all of a sudden "better" takes on a new light
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I think you'll be cold with a Espar D2 or D4 heater for your size boat. We had one on Hobo and it worked hard (we're 42') . They are a PIA to install with all the duct work. Think 4" and 3" holes to get the heat forward evenly.
We had a Webasto DBW 2010, 45,000 BTU hydronic system on our last boat that I helped install. 3/4 supply lines down one side of the boat with the return lines back on the other. You'll always have hot water. All the lockers were warm. Easy to set up with separate zones. We had a separate thermostat for the head on a timer. We'd get up in the morning and the head would be 70 degrees. We found locating the radiators was easier than running continuous duct work from the engine room all the way forward and into the pilot house. You can buy a kit complete for $7,200.
Sure Marine
Hopefully Phil will jump in. He installed a big Webasto system on his boat.
ksanders
Moderator Emeritus
OK, I've installed three hydronic systems, and two forced air systems on my own boats over the years. These were "from scratch" installations.
The systems have been Espar, toyotomi, and Wallas brand.
Hydronic is much more complicated to install. You need to route two heater hoses and DC power to each heat exchanger.
You also have to design the system so that you have a coolant tank at the highest point. You also have to design in several valves so that you can use a separate pump to pump coolant through the system.
You also need to design or purchase an electrical interface system to add zone control to the heat exchanger motors.
Startup can be a bear, getting all of the air purged from the system.
The advantages of hydronic are that since the hoses are 3/4" instead of 3" air ducts routing is easier. Building in zone control is easier because of this. You can use the hydronic to heat up potable water, another advantage.
Forced air systems are much less complicated to install. They generally come with the electronics/thermostat as part of the kit.
With a forced air system, you can utilize outside air for a portion of your air flow, providing ventilation to your boat.
The challenge with forced air is zone control. On a larger boat like our 47 we need heat allot in the cabins, less in the salon, and even less in the pilot house. Forced air systems are fairly limited in their BTU output. There are larger forced air systems but for the most part they are limited to around 10K BTU per unit.
Both units are very noisey for the most part. They sound like a turbo when outside the boat.
On our latest boat a 47' pilothouse we went with Wallas forced air furnaces. These provide both zone control and ventilation.
The Wallas units also have an advantage of being very quiet. You cannot hear them running. Another advantage of the Wallas units is their new thermostat. Instead of a simple on-off their thermostats modulate the flame so that you get just the right heat output for your situation.
We went with a 10KW unit to serve the cabins, a 10KW unit for the salon, and a 7.5KW unit for the pilothouse.
The systems have been Espar, toyotomi, and Wallas brand.
Hydronic is much more complicated to install. You need to route two heater hoses and DC power to each heat exchanger.
You also have to design the system so that you have a coolant tank at the highest point. You also have to design in several valves so that you can use a separate pump to pump coolant through the system.
You also need to design or purchase an electrical interface system to add zone control to the heat exchanger motors.
Startup can be a bear, getting all of the air purged from the system.
The advantages of hydronic are that since the hoses are 3/4" instead of 3" air ducts routing is easier. Building in zone control is easier because of this. You can use the hydronic to heat up potable water, another advantage.
Forced air systems are much less complicated to install. They generally come with the electronics/thermostat as part of the kit.
With a forced air system, you can utilize outside air for a portion of your air flow, providing ventilation to your boat.
The challenge with forced air is zone control. On a larger boat like our 47 we need heat allot in the cabins, less in the salon, and even less in the pilot house. Forced air systems are fairly limited in their BTU output. There are larger forced air systems but for the most part they are limited to around 10K BTU per unit.
Both units are very noisey for the most part. They sound like a turbo when outside the boat.
On our latest boat a 47' pilothouse we went with Wallas forced air furnaces. These provide both zone control and ventilation.
The Wallas units also have an advantage of being very quiet. You cannot hear them running. Another advantage of the Wallas units is their new thermostat. Instead of a simple on-off their thermostats modulate the flame so that you get just the right heat output for your situation.
We went with a 10KW unit to serve the cabins, a 10KW unit for the salon, and a 7.5KW unit for the pilothouse.
psneeld
Guru
I agree...was wondering...ever think of baseboard instead of exchanger units? Would simplify and reduce interior noise...I may try it...
ksanders
Moderator Emeritus
Most boats do not have room for baseboards that are long enough to be effective.
Then you have the issue of zone control. you'd need zone valves, etc...
You could do it, but I think it might not save you much in the way of trouble.
psneeld
Guru
I know...but if I have to go to heat exchangers...hot forced air might be just as good for my boat...
ksanders
Moderator Emeritus
Its all a tradeoff.
Nothing wrong with forced air.
Depending on how much duct you need to run installation time can be as low as about a day and go up from there.
Plan on a week to get hydronic installed and tested.
psneeld
Guru
thanks!
FF
Guru
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- Oct 12, 2007
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Used to sell/ install these units.
Biggest concern to operation is to only use LARGE sized wiring to install, regardless of Mfg claims.
10 Ga would be minimum for close install, 8ga is almost always better.
The problem is that most were bus or truck heaters , 14.4V being normal.
The amperage goes way up when operating off a 12V batt that may be half full.
Air is cheaper and quicker , but ducts take up room and waste heat behinf walls , in cabinets etc.
Hydronic is best for a full time dockside (120V - 24/7) where the extra loads of toe kick heaters will not also be dragging down the batt bank.
Base board radiation is best of all, but almost impossible to retro fit on an existing interior.
For a new build nothing would be better .
FF
Biggest concern to operation is to only use LARGE sized wiring to install, regardless of Mfg claims.
10 Ga would be minimum for close install, 8ga is almost always better.
The problem is that most were bus or truck heaters , 14.4V being normal.
The amperage goes way up when operating off a 12V batt that may be half full.
Air is cheaper and quicker , but ducts take up room and waste heat behinf walls , in cabinets etc.
Hydronic is best for a full time dockside (120V - 24/7) where the extra loads of toe kick heaters will not also be dragging down the batt bank.
Base board radiation is best of all, but almost impossible to retro fit on an existing interior.
For a new build nothing would be better .
FF
