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[sstan]

Just wonder if this is possible or if anyone has tried this idea.  My OWB seems to be hotter in the front of the stove.  Water is pulled and returned to the back of the stove.  I do not know what the guts look like inside of the unit (NCB-175).  I was wondering if on my return .. I plan on moving it to the top of the boiler this summer and moving the pump to one of the bottom ports to give the pump more head pressure ..  if on the return port can I extend via a pipe inside the water jacket so the water dumps out more to the front of the unit?  Not sure I am explaining it very well ..

[R W Ohio]

If you would look under Home Made of this site,
 the fourth picture shows that the return pipes at the top of the stove go almost to the firebox door end of the stove.The outlet for the pumps are at the lower part of the water jacket below the the port for the return.We seem to have a good mixing of the water this way.

RW

[MarkP]

Hi Steve,,, I think you have the right idea, and the pics Ron posted are a good example of how it's done right.  Since mine is homemade, and I really didn't know any different, I made my supply and return both on the back, and only about 18" apart, so I know I am pumping the "cold" water  that is coming back into the stove, before I get the chance to use the hottest water that is in the front.  I think I lose alot of efficiency this way.  I don't know of a good way to extend pipes to the front of my stove now, other than running them over the top, and dropping a pipe DOWN into the front of the water tank.  I could run a pipe in from the back, but there would be no way to support the end inside the stove without cutting into the tank.  I could make an "inspection plate" on top of the stove, and use that as an access to a support, I suppose.  I have a few changes to make when heating season is over, and this is one of them.

[willieG]

mark when i made my stove i used a 2 "  female bushing (coupler) in the back of my stove. this allowed me to make a long 1" pipe with a 2" nipple over it so i could screwit into the stove and take it out if needed...you could retro fit your stove something like this if needed

i have my cold dumping right in the rear of my  stove at the bottom and i pull my hot off the top of the stove about half way to the front, right at my aquastat
seems to work ok
im' not sure if i can get a photo or not (becasue of my insulation) but i will take a look

[MarkP]

I understand what you are saying.  My watertank is 4 feet long, so I guess a 1" pipe 3 feet long wouldn't be too bad.  I was trying to picture the weight of a long piece of pipe with nothing to support the end in the tank, but I guess the weight wouldn't be that much, supported by the back end of the stove that is 1/4" A36 steel.

As for pulling the water off the top of the stove where the water is hotter, it kinda' makes sense.  Please pass along any pics you might have.  We all appreciate the photos and ideas.

[yoda]

 My Shaver 165 does the same thing, sometimes I can hear water starting to boil at the front of the stove, just above the door.  The water at the back is only 160. I think this summer I am going to run a return line on the top outside of the water jacket, drill a hole and run the return pipe to dump in the front of the stove.

[willieG]

I understand what you are saying.  My watertank is 4 feet long, so I guess a 1" pipe 3 feet long wouldn't be too bad.  I was trying to picture the weight of a long piece of pipe with nothing to support the end in the tank, but I guess the weight wouldn't be that much, supported by the back end of the stove that is 1/4" A36 steel.

As for pulling the water off the top of the stove where the water is hotter, it kinda' makes sense.  Please pass along any pics you might have.  We all appreciate the photos and ideas.

here is a photo showing my connection for the feed line to the house..you can't see the 2 inch coupling for the insulation but you can get the idea...the 2 inch coupling is welded into the back of the water jacket (mine is 3/8 mild steel) and then a 2 inch nipple is screwed into that, then the other pipe is welded into the nipple..this lets me takeit out if i like..make a new one of a different length or whatever is needed

i have never removed it yet and don't think i ever will but i liked the option at the time i built it
i built the stove with the option of gouging the weld between the fire box and the water jacket at the front of the stove and being able to slide the fire box out of the jacket in case either one ever neede replaced

my firebox slides on a channel iron rail on the bottom and slides into a "guide" at the back of the stove to hold it in place and to keep it from "floating" in the water jacket.nothing is welded inside so it can be taken apart

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[sstan]

I plan on doing some summer changes but doubt I want to cut any holes in a new furnace!  I do plan on moving my pump to one of the lower ports .. from what I am hearing from dealers and even NC the pumps last longer with more head pressure and the temp diff is not that big of a factor.  What I am thinking is that if I move my retrun to the opposite side and to the top port .. then since it is a 1 1/2 in port that must be adapted down to a 1" size for my pex .. can I get a 1 1/2 to 1 bushing .. get a 1" pipe.. maybe 2 or three ft long  (black or galvanized?) .. get it threaded say 4 inches and thread it in the bushing so it sticks out the end and I hook my pex on it.  Not sure if that was clear enough explaination or not.

steve

[R W Ohio]

We run ours with the the pump on the lower outlet and the return at the port above it.We also have another set of supply and return openings on the other side that are no being used.It might not be a bad idea to cross them for a better mixing of the water in the water chamber.It should not be that much of a job to change it. Let us know how it goes after you do it.

[MarkP]

Hey Bill,,, thanks for the photo.  I see how you made the pipe work.  That will be easy to do on my stove.  The question now is whether to pull the water from the top, or the bottom.  Seems like pulling it off the top makes for hotter water.  I will get the pipes in and then work out the details.  It looks like the more distance between  the return and supply, the better the circulation will be.  More distance has to be better than what I have now.  My supply and return are only about 18 inches apart. 

I'm making a list of the changes I plan on making before next heating season.  This has been a learning experience.  I appreciate everyones help.

[willieG]

from what I am hearing from dealers and even NC the pumps last longer with more head pressure
steve

this could very well be true sstan. my pump is over 8 years old  and it must have about as much head pressure as you can get...it is in the basement of my home at almost the lowest level in my system and i have never had a problem with it yet

[sstan]

yea .. the owners manual says install the pump in the high port but I just tbought a new larger pump (going to try and heat my swimming pool this summer and the stock pump is too small).  Anyway I was talking to a dealer in uppper NY and then the tech rep at NC trying to fiquer out how big a pump I needed and they have since changed their mind.  Seem that these types of pumps are water lubricated and while convensional thinking was to draw the hottest water off the top of the stove the extra head pressasure from drawing from the lower port provided more head and thus lube to the pump and they do not wear out as fast! 

[willieG]

im not so sure you need a bigger pump to move more water to heat your pool...a bigger exchanger may be in order it takes a lot of btu to heat a pool..woo

if your pool is 20,000 gal that is about 200,000 pounds and at 1 btu to raise 1 pound of water 1 degree..well thats a lot of btu's..if you start with a pool temp of 60 and heat it to 75 that is 15 degrees x 200,000 = 3 million btu  at 100 % stove efficiency (and we know we don't have that) we are likley around 55 to 65 % efficient but we also do not know the heat loss of your pool while heating it up so lets  say for easy figuring we are at 50% efficient  so now we need another 1.5 million btu's we are up to 4.5 million btu or about 1 face cord of good wood, then to maintain that temp is a real unknown as day and night time temps can not be accurate and we dont know the heat loss of the pool

i do know that my uncle heated his pool woth gas and told me in may and june his gas bill for the pool was more per month than his gas bill for the house in january so that should give you an indication of the amount of wood you will use

you could guess (and only guess) that to heat your pool for a month would be more wood than you burnt this past month

i would take another guess that as long as you are NOT losing more than 20 to 25 degrees from the heat exchanger your pump is big enough..if you are losing less, you could go with a bigger exchanger..remember you don't want to draw btu 's from your stove than you can't keep up to.

another  guess..if i was heating a pool with my stove i would want my stove to be able to shut off once in while or at least be able to (with a decent supply of wood in it) maintain a steady temp of about 130 to 140 while the pool heater is running

all these opinions are just that..and i have no facts to back them up and they may be entirely wrong but i post them anyway just for discussion purposes..and look forward to any others so we may see other thoughts and maybe get good suggestions and discussions going