Chineese Diesel Heaters - Extras

where are most finding the best exit point in the hull for exhaust
The best is so the exhaust tube is short, sloping slightly downward and a minimum 8" above the waterline.
 
Got it ! seems the ideal spot is below the rub line but 8 inch above the water line and sloping slightly down , and not in the way of a fender !
I hate cutting into the hull .... even 8 inches above the water line but better than getting exhaust in the helm , thanks Fog ducker and foxsea and ryanb for the heads up !!
 
Height of discharge above waterline listed anywhere from 8" to 24" by various manufacturers, encompasses sailboat applications, as well. Sailboats heel. Powerboats, not too much. 24" is difficult for small boats to achieve. I personally believe that, with the correct (angled) discharge fitting, 8-12" is ample in a powerboat. Consider where your sink drain is. Certainly not 24" above the WL on smaller vessels.
 
Height of discharge above waterline listed anywhere from 8" to 24" by various manufacturers, encompasses sailboat applications, as well. Sailboats heel. Powerboats, not too much. 24" is difficult for small boats to achieve. I personally believe that, with the correct (angled) discharge fitting, 8-12" is ample in a powerboat. Consider where your sink drain is. Certainly not 24" above the WL on smaller vessels.
The difference being a sink drain can have a seacock or valve in place which the exhaust does not and is open to water intrusion should anything happen there is no way to stop water from entering your boat through a 1” hole..
 
The difference being a sink drain can have a seacock or valve in place which the exhaust does not and is open to water intrusion should anything happen there is no way to stop water from entering your boat through a 1” hole..
Most production boats with sink drains (above WL) will not have seacocks. If you do have water coming in, putting the boat more than 8 " below the water line, you have a much greater problem to deal with first. But, like all good boaters would, have a tapered plug available, just in case. ;)

After talking with a fellow who has installed many diesel heaters he says small boats are always challenging for installation. Regarding exhaust outlets, first, use a quality tube and the proper clamps with exhaust sealant. Second, keep the exhaust short - about a meter long is ideal. Keeping the tube level or sloping downward toward the outlet is recommended. Put an 8" upward gooseneck in the exhaust just ahead of an angled down and back thru-hull outlet. 12" above the waterline is recommended for powerboats. He confirms a higher level applies to sailboats. Wrapping the exhaust tube with high-heat tape protects the surroundings (maintain clearances) and eliminates condensation. Also ensure the exhaust is well clear of intake vents, hatches and canvas-enclosed cockpits.
 
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From the Wallas install instructions. I have a diesel stove/heater. But I’m still going to add a Chinese diesel heater for the wheelhouse and windows.
 
View attachment 74837
From the Wallas install instructions. I have a diesel stove/heater. But I’m still going to add a Chinese diesel heater for the wheelhouse and windows.
This is interesting and contradictory: from what they say "never submerge" the heater cannot exhaust through the hull sides in any boat that is actually sailed - only through the transom, near center. On a reach, a sailing vessel is heeled well over and the sides are constantly wet or submerged.
 
Height of discharge above waterline listed anywhere from 8" to 24" by various manufacturers, encompasses sailboat applications, as well. Sailboats heel. Powerboats, not too much. 24" is difficult for small boats to achieve. I personally believe that, with the correct (angled) discharge fitting, 8-12" is ample in a powerboat. Consider where your sink drain is. Certainly not 24" above the WL on smaller vessels.
yes , I agree its tough to find a spot that ticks all the boxes. every boat design will have different challenges.

personally I didn't put mine that close to the water line as I was told by a heater installer that the further away the better, again that is just one guys opinion. and i drilled the hole so now I'm committed.
 
This is interesting and contradictory: from what they say "never submerge" the heater cannot exhaust through the hull sides in any boat that is actually sailed - only through the transom, near center. On a reach, a sailing vessel is heeled well over and the sides are constantly wet or submerged.
Most sailboats are pretty tubby in the middle. The aft third pinches into the stern, keeping the waterline lower than the tubby middle third.
The transom exits the water pretty clean when moving, that would be the best location
 
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