air intake hose and filter options on Chinese diesel heater

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paulga

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In a video the Youtuber gave an advice that the restriction of air intake should be reduced. Following this advice, I'm considering using a 30mm ID intake hose with a 30 to 24mm reducer, instead of the 24mm aluminum hose that came with the heater. The air intake will draw air from salon inside for easier installation. heatso website has too many options leaving me confused so I want to get some clue here.

Where can I buy one of the two recommended hoses shown below and the reducer:

Image_20240409193455.jpg

what is the name of the air filter and the adapters as shown below:

Image_20240409193506.jpg


Image_20240409193501.jpg


video source: www.youtube.com/watch?v=NCAzEDWwU8c
 
combustion air intake or cold air intake?
The hose in your hand looks like combustion air. Why would you increase the size of that? what did the article say would be the benefit
 
I’ve only used the intake silencer on the combustion air inlet.
The only reason to worry about the combustion air intake is if the heater is in a small area with restricted air flow. The combustion air intake can’t deal with the negative pressure if the main air is robbing it.
So, either route the main air intake to another space, or the combustion air. In either case, the aluminized paper ducting is the easiest to work with. It’s lightweight and holds its shape well.
Use a silencer on the combustion air intake and extend the hose as needed, just keep it as short as possible.
If the main air is already routed outside the mounting space, just use the silencer and pull the combustion air from the mounting area.
 
But why would the intake air be in the same space as the combustion intake? Mounted in the ER is what I am asking. The intake air should come from the cabin to circulate and heat faster. The combustion can be in ER to suck up all the ER fumes.
 
But why would the intake air be in the same space as the combustion intake? Mounted in the ER is what I am asking. The intake air should come from the cabin to circulate and heat faster. The combustion can be in ER to suck up all the ER fumes.
I thought Jay was mounting this in a locker in the aft stateroom. Maybe this is a different installation?
 
combustion air intake or cold air intake?
The hose in your hand looks like combustion air. Why would you increase the size of that? what did the article say would be the benefit
combustion air intake (C).
I've watched John's video series. The benefit of going up a size is to reduce air restriction for an intake hose over 50cm
 

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I’ve only used the intake silencer on the combustion air inlet.
The only reason to worry about the combustion air intake is if the heater is in a small area with restricted air flow. The combustion air intake can’t deal with the negative pressure if the main air is robbing it.
So, either route the main air intake to another space, or the combustion air. In either case, the aluminized paper ducting is the easiest to work with. It’s lightweight and holds its shape well.
Use a silencer on the combustion air intake and extend the hose as needed, just keep it as short as possible.
If the main air is already routed outside the mounting space, just use the silencer and pull the combustion air from the mounting area.

this is the air filter that comes with the package: the mesh material is flimsy, the area is too small.

Image_20240414212424.jpg


The white filer recommended in John's video has a larger mesh area, but I didn't find the same one in the plumbing stores nearby, so I'm thinking to buy this one

in addition to the clamps, is silicone gasket usually used on the intake hose inside to make the connection air tight?

Screenshot 2024-04-14 213643.png
 
I don’t worry so much about the air intake. I use the espar silencer, Espar / Eberspacher Airtronic Combustion Air Intake Silencer
Clamp it to the heater, no sealant. Fasten the loose end so it doesn’t flop around.
Where exactly are you planning to pull the combustion air from?
Personally, if the locker had louvered doors I’d just run the silencer and pull it from within the locker.
 
One picture is of a screen/silencer, the other is just a screen. The second has more screen surface area, and if that pleases you and you don't care about noise, that one would be fine. The "silencer" screen works on the basic theory that sound travels best in a straight line. The only thing the silencer adds is a convoluted air passage, but it cut down on the fan whine. The intake noise is high frequency and might not even be a problem if the heater is in the engine room. We like things really quiet at anchorage, and know that some others do, so went with the silencer and muffler.

The screen area on the silencer is less, but it is still more than the cross section of the connecting duct, meaning that it really is no more of a "restriction" than the duct itself. In fact, if one doubled the length of the intake duct to "send the noise overboard," they would double the air intake restriction, i.e., way more restriction than adding the silencer. That would be the only reason to go with a larger intake duct and it would probably need to be larger than a few millimeters to make a difference. I actually shortened the length of my intake duct to lower the restriction.

Not much reason to worry about the screen mesh rating. I once had a mechanic look at the intake of my Isuzu D500 diesel and asked him if I needed a better air filter. He called what I had a "gravel guard" and said that if I had abrasives flying around the engine room that could pass through that screen I has bigger problems. Same is likely with a diesel heater. If you need to worry about the screen getting clogged with no-see-ums, you need a different cruising area.
 
I don’t worry so much about the air intake. I use the espar silencer, Espar / Eberspacher Airtronic Combustion Air Intake Silencer
Clamp it to the heater, no sealant. Fasten the loose end so it doesn’t flop around.
Where exactly are you planning to pull the combustion air from?
Personally, if the locker had louvered doors I’d just run the silencer and pull it from within the locker.
I'm still planning to place the heater inside the salon closet. the combustion air will also be from the closet.

Is the dosing pump powerful enough to draw diesel from the racor 500FG? if so, is it still necessary to install the fuel filter that comes with the heater?
 
One picture is of a screen/silencer, the other is just a screen. The second has more screen surface area, and if that pleases you and you don't care about noise, that one would be fine. The "silencer" screen works on the basic theory that sound travels best in a straight line. The only thing the silencer adds is a convoluted air passage, but it cut down on the fan whine. The intake noise is high frequency and might not even be a problem if the heater is in the engine room. We like things really quiet at anchorage, and know that some others do, so went with the silencer and muffler.

The screen area on the silencer is less, but it is still more than the cross section of the connecting duct, meaning that it really is no more of a "restriction" than the duct itself. In fact, if one doubled the length of the intake duct to "send the noise overboard," they would double the air intake restriction, i.e., way more restriction than adding the silencer. That would be the only reason to go with a larger intake duct and it would probably need to be larger than a few millimeters to make a difference. I actually shortened the length of my intake duct to lower the restriction.

Not much reason to worry about the screen mesh rating. I once had a mechanic look at the intake of my Isuzu D500 diesel and asked him if I needed a better air filter. He called what I had a "gravel guard" and said that if I had abrasives flying around the engine room that could pass through that screen I has bigger problems. Same is likely with a diesel heater. If you need to worry about the screen getting clogged with no-see-ums, you need a different cruising area.
the air passage is straight through, so this one will not have any silence effect

Image_20240415124534.jpg


in John McK 47's CDH videos, he weighed the air filter to be more important
his test at 3:03 of this video actually shows higher decibel with a silencer attached.
 
I'm still planning to place the heater inside the salon closet. the combustion air will also be from the closet.

Is the dosing pump powerful enough to draw diesel from the racor 500FG? if so, the manifold can be after the racor. Then is it still necessary to install the fuel filter that comes with the heater?
 
I'm still planning to place the heater inside the salon closet. the combustion air will also be from the closet.

Is the dosing pump powerful enough to draw diesel from the racor 500FG? if so, is it still necessary to install the fuel filter that comes with the heater?
The dosing pump shouldn’t have any problem pulling through the racor. I’d ditch the other filter. Those little pumps push better than they pull, so keep the pump close to the fuel supply.
 
Concur with above, pump should have no problem drawing through the Racor.
Orientation of the pump could be important though...
 
I don’t worry so much about the air intake. I use the espar silencer, Espar / Eberspacher Airtronic Combustion Air Intake Silencer
Clamp it to the heater, no sealant. Fasten the loose end so it doesn’t flop around.
Where exactly are you planning to pull the combustion air from?
Personally, if the locker had louvered doors I’d just run the silencer and pull it from within the locker.

is silicone sealant needed on exhaust hose connections to the heater and to the through hull?

are exhaust hose clamps directly clamping on metal, or over a layer of insulation?
 
is silicone sealant needed on exhaust hose connections to the heater and to the through hull?

are exhaust hose clamps directly clamping on metal, or over a layer of insulation?
You can use exhaust sealer if you want, I haven’t had any trouble just clamping the exhaust tubing directly to the fittings. Clamp directly on the metal hose, then wrap with insulation.
 

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