The Diesel heater thread

[cadillackid]

Originally Posted by o1marc

Don't they only use the bus fuel for power, it's not connected to the motor?

Correct, the AIR HEATERS dont touch anything but the fuel tank.. a coolant heater can be plumbed in so it circulates through the engine coolant loops..

or it could be used closed-loop with its own expansion tank and circulate just through its own dedicated heater coils if you wish...



-Christopher

[Brewerbob]

Originally Posted by banman

I would be leary of plumbing a 'cheap' unit into my buses engine -- I wouldn't want anything that could damage or reduce the reliability of my engine...

Y-fitting to the engine coolant. If the pump to the radiant heat dies, the coolant is still going to take the path of least resistance which would be thru the radiator and engine block. Worst case the cheap one explodes and you have a coolant leak. The RE bus to the front defrost is a hell of a lot of coolant. If you spewed enough the engine runs dry and didn't notice, it's because you're already a zombie and just don't care.


My bus also has shut off valves where it comes into the bus from the engine. In summer those would be closed anyway.

[Brewerbob]

Originally Posted by cadillackid

Correct, the AIR HEATERS dont touch anything but the fuel tank.. a coolant heater can be plumbed in so it circulates through the engine coolant loops..

or it could be used closed-loop with its own expansion tank and circulate just through its own dedicated heater coils if you wish...



-Christopher

Or a third loop with a heat exchanger for hot sink/shower water. That's my plan. I should probably start shopping for said exchanger.

[o1marc]

Originally Posted by Brewerbob

Y-fitting to the engine coolant. If the pump to the radiant heat dies, the coolant is still going to take the path of least resistance which would be thru the radiator and engine block. Worst case the cheap one explodes and you have a coolant leak. The RE bus to the front defrost is a hell of a lot of coolant. If you spewed enough the engine runs dry and didn't notice, it's because you're already a zombie and just don't care.


My bus also has shut off valves where it comes into the bus from the engine. In summer those would be closed anyway.

He was referring to an "air" cooler, not a coolant heater.
My air cooler came with it's own tank, or plumb to bus tank. It was not expensive.

[Brewerbob]

Originally Posted by o1marc

He was referring to an "air" cooler, not a coolant heater.
My air cooler came with it's own tank, or plumb to bus tank. It was not expensive.

Um, you can't plug an air heater into your engine.

[banman]

Originally Posted by o1marc

Don't they only use the bus fuel for power, it's not connected to the motor?

The coolant heaters are plumbed into the engines cooling system and circulate the engines coolant through the system. This is good for over the road truckers who have instant heat/defrost when they start out after sleeping in their cab all night.

But cadillackid makes an interesting point that you could isolate the buses heater cores from the engine...

My preference is the propane gravity furnaces which take no electric power at all -- they are hard to find and less ideal for large spaces but was great in my 14' camper when I lived off-grid.

[PNW_Steve]

I have seen, and am going to duplicate, a coolant heater plumbed in a manner that allowed you to select the heat source and destination. That way you can use the coolant heater to preheat the engine or to heat your interior or both.

While you are driving you can use either the coolant heater or the engine coolant to heat your interior.

[Brewerbob]

Originally Posted by cadillackid

-Christopher

So, here's a question for you Chris. How many BTU/hr do I need for instant hot water for the shower? Below are a couple of random heat exchangers. One is meant for home brewing and the other has a rating in the name. I'm guessing my potable water is 50° on a cold day with the heat in the bus off or running low. Shower water is 104° give or take. The Webastco output temp is ...? I see BTUs on their data sheet but not temps.



No BTU/hr
https://www.amazon.com/gp/product/B0...CCQDKPZI&psc=1

280,000 BTU/hr
https://www.amazon.com/gp/product/B0...O3Q2HX8Y&psc=1

[o1marc]

Originally Posted by banman

The coolant heaters are plumbed into the engines cooling system and circulate the engines coolant through the system. This is good for over the road truckers who have instant heat/defrost when they start out after sleeping in their cab all night.

But cadillackid makes an interesting point that you could isolate the buses heater cores from the engine...

My preference is the propane gravity furnaces which take no electric power at all -- they are hard to find and less ideal for large spaces but was great in my 14' camper when I lived off-grid.

I was replying to a post where YOU asked about Diesel "AIR" heaters, not "COOLANT" heaters.

[o1marc]

Originally Posted by Brewerbob

Um, you can't plug an air heater into your engine.

That was my point Bob.

[Brewerbob]

Originally Posted by PNW_Steve

I have seen, and am going to duplicate, a coolant heater plumbed in a manner that allowed you to select the heat source and destination. That way you can use the coolant heater to preheat the engine or to heat your interior or both.

While you are driving you can use either the coolant heater or the engine coolant to heat your interior.

That's all valving and loops but also what I want.




Engine coolant on and diesel heater off, floor on... when driving to Alberta.

Engine off, floor off, diesel heater on, heat exchanger and hot shower ... in FL.

Diesel heater on, floor on, engine off, circulate thru engine block ... in Alberta.

[Brewerbob]

Originally Posted by o1marc

That was my point Bob.

My Y fitting, which was supposed to be T fitting, comment was quoting a comment where he said he didn't want to mess up his engine. There are knock offs of both the air and coolant heaters tho there certainly seem to be a lot more air heaters out there than the coolant one.

[o1marc]

Originally Posted by Brewerbob

My Y fitting, which was supposed to be T fitting, comment was quoting a comment where he said he didn't want to mess up his engine. There are knock offs of both the air and coolant heaters tho there certainly seem to be a lot more air heaters out there than the coolant one.

Why didn't you quote that post?

[Brewerbob]

Originally Posted by o1marc

Why didn't you quote that post?

I did.

Quote:
Originally Posted by banman
I would be leary of plumbing a 'cheap' unit into my buses engine -- I wouldn't want anything that could damage or reduce the reliability of my engine...

Y-fitting to the engine coolant. If the pump to the radiant heat dies, the coolant is still going

Since you can't plumb an air unit into your engine, he must have been talking coolant.

Tho just to play devil's advocate now, I guess you could plumb an air unit into your engine with the right engine. I have a grid heater in my bus instead of glow plugs. I've no idea if the outlet of the diesel air heater would be enough to replace a grid heater tho. Might be interesting to find out if the grid dies and costs $600 when the air heaters are only $150 or whatever.

[o1marc]

Originally Posted by Brewerbob

I did.


Since you can't plumb an air unit into your engine, he must have been talking coolant.

Tho just to play devil's advocate now, I guess you could plumb an air unit into your engine with the right engine. I have a grid heater in my bus instead of glow plugs. I've no idea if the outlet of the diesel air heater would be enough to replace a grid heater tho. Might be interesting to find out if the grid dies and costs $600 when the air heaters are only $150 or whatever.

You quoted me on post #125

I doubt an air heater gets as hot as your grid heater.

[PNW_Steve]

Originally Posted by o1marc

You quoted me on post #125

I doubt an air heater gets as hot as your grid heater.

How hot do his air heater and grid heater get?

[o1marc]

Originally Posted by PNW_Steve

How hot do his air heater and grid heater get?

If I knew I would not use the word doubt.

Grid heaters run around 1200*, I doubt the air heaters are anywhere near that.

[PNW_Steve]

Originally Posted by o1marc

If I knew I would not use the word doubt.

Grid heaters run around 1200*, I doubt the air heaters are anywhere near that.

Ok. The tone of your post led me to believe that you knew.

Apologies

[o1marc]

Originally Posted by PNW_Steve

Ok. The tone of your post led me to believe that you knew.

Apologies

I was completely guessing, but my theory seems valid that it takes more temp to make a grid glow, than what it takes to heat air for the cabin. I commend thinking outside the box, but sometimes it's just unreasonable.

[LoveBusTreatery]

I feel like I have seen people wire these to timers or thermostats for temperature control after noticing that the low setting is too high. Anyone tried this?