Making my ProHeat more Efficient

[JohnEd]

Charlie,

See?  This was my point a while back.  Busguy1 reads 252 degrees at his ex and you read 300.  Things aren't right in River City.

If you have a small boiler, and I have never laid eyes on one, and you want, say, 150 degree water you will have a flame "so high".  If you want 185 degree water you will have a larger flame and your ex temp will go up along with you circulated water.  These units can't be efficient because of space and weight limitations.  45K BTU is the spec and their flame is set to produce that much.  Reduce the size of the flame and you will gain efficiency cause the boiler will be able to absorb that small amt of heat with the reduced combustion air flow more fully.  You don't need that max heat to maintain temp, only to start a cold sys in short order.  From what i have read you are burning twice the fuel as others and that breaks to $150 a month.  I think the answer is to have a variable flow of fuel and also vary the combustion air flow accordingly.  How that would be achieved I will leave to those that can put one on the bench and eyeball it.  I have been through this very issue with a propane furnace and all the principles are the same.

My heat pump SEER rating jumped a full point simply because I added a variable speed blower in the air handler.  Oh Crap!  Here comes Nick of AC.   Just kidding Nick   I love ya and you Are the Man where AC and other topics are concerned.  What do you think about my crazy idea?

Don't you make a 45K PH from a 35K PH by changing the jets and blower?  Isn't that what is in the conversion kit?  How many BTUs do you need to maintain 76 degrees inside in 46 degree weather?  A 1.5K watt heater will increase my temp 30 degree and that is a 30 foot S&S without thermo glass.  I think a well insulated 40 foot bus should maintain that on even less.  Don't you?  100 gallons a month would leave you a cinder if it was efficient.  Heating water and bays does complicate the picture though.

I suggested using the ex a while back but was told the PH would Fault due to low air flow if even to many bends were put in the ex line.  OK so the heat ex will be a really big low restriction pipe.  Hows that?  That VW idea was good but those puppies were dealing with ex temp gas at a high flow rate.  They are short and only a little more than an inch in diameter so it would be restrictive and not be able to absorb 100% of the energy.  The idea is good though.

This is really interesting.  I wish i could touch furnace things and smell diesel while we discuss this and try "stuff".

Thanks for all your help and i will buy one of those PH boilers from you one day if the coach I buy doesn't have one already.

John

John

[captain ron]

Fumbling around in the dark and holding the gun as close as I could I got a reading of 385 degrees. I'll try again in the morning when I can see what I'm doing.

[JohnEd]

Charlie,

Wow!   That is a lot of energy going out the window.

Hang one of those oven thermometers on the ex port.  I too like my gun , though.

Till morning, Bud

John

[donnreeves]

I just got 534* at the elbow where it exits the PH. I think it is actually a little higher, but if I moved the laser closer toward the PH the gun shut off. Must have a high limit on it. Yes there is some serious heat that could be recoverd there.   Donn

[captain ron]

Right now my exhaust is just pointing strait down with no elbow waiting to figure out what I was going to do. So when Ross gets back we'll attack it with a vengance. I just got 511 but as I said I have no way to hit on the metal and with no elbow the heat all escapes quickly without hitting any obstructions. I imagine it would get close to 600 degrees F.

[makemineatwostroke]

Donn reading is about right in my manual the reading should be below 575 for best performance but it doesn't say how much below.I found it 550 to 574 degrees reading taken at the unit that is a lot of wasted heat

[Paso One]

another way would be to run the exhaust through vw beetle exhaust heat exchangers and circulation fan the air back into the bus.  That would be kinda instant heat too.
http://www.jcwhitney.com/autoparts/Product/tf-Browse/s-10101/Pr-p_Product.CATENTRY_ID:2002914/showCustom-0/p-2002914/N-111+10201+600002305/c-10101

the same would work for genny exaust.

my old vw heat would burn you if you weren't careful

you could cicrulate the hot air into the bays and heat up all that thermal mass and help keep the bus warmer.  you can circulate the hot air around the tank tha youve already built to help keep it warm.

take pics and give feedback so i can do mine too

Awesome Idea NewBeeMC9  I have a few of those heat exchangers and have another application that it will work perfect. 

It would also work as you suggest for heating another bay or area, as the discharge side can be piped anywhere.

[NewbeeMC9]

on the vw exhust thing, you can put a couple in series or parallel, depending on what your exhaust flow needs are. just make sure moisture in the exhaust can drain out.

they are cheap and already made.

probably not most effecient , but i don't think you can grab 100% of the heat

they dont take up much space

then you can use the air at a reduced temperatue to heat something you don't want to point 600 degrees at.  like your resivoir tank, Or veggie oil or fuel tank.  Would help get the bus warm in a hurry.

you get a bend to help with some noise reduction if that is needed


do it your way,  (so i can do it mine )


   ps what's your application there paso one,  enquiring minds want to know