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Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 8:51 pm
by Ted4
Ok, another question for u pros. I have a Efm 350 that will sit in my coal shed 60 ft away. I'm ready to pull the trigger and buy the feed and return pipe. I have 3 zones in the house currently. Radiant in slab. 1/2" or 5/8 ID. not really sure. Should I go with 11/4" in trench, or 1"? The extra cost of bigger pipe is about 200.00 and probably a few hundred more between pipe and valves for larger size. The money really isn't the issue, I want to do it right. The question is, if I'm only pulling 3 zones with a total volume less than what a one inch pipe carries, is the bigger pipe overkill?

Re: Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 9:26 pm
by windyhill4.2
Depends on house size & BTU demand.I set up our OWB in 2006 with 1" & Taco 007 circulator which runs continuously .We have 180' from the OWB to our house ,this heats our house & runs thru a plate heat exchanger for DHW then goes to second house to do the DHW there too b4 returning to the OWB 500+ feet later. Our house is 24x60 with poor insulation,leaky windows , we heat to 74*,unlimited DHW. Some will say this won't work,it does but bigger is generally better,BUT $$$$.....is it worth it ??? Not saying my way is right just giving my 7.5 yrs experience .

Re: Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 9:32 pm
by Ted4
No kidding? An 007 from that far away? I'm just getting all my materials ready, but I thought for sure that would be too small. Just an assumption, no practical experience behind it. I put my own oil boiler in, and actually went to a night school votech for heating and a/c, but I've got so many questions. U guys are gonna be banning me soon.

Re: Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 9:53 pm
by StokerDon
Ted,

You will likey need 1.25" PEX. Read this http://s3.pexsupply.com/manuals/1350570919940/836 ... D_FILE.pdf Then you can make you own calculations for PEX size and pump size.

I very recently installed a stoker boiler in my garage Yellow Flame, A Christmas Stoker Boiler The guys on this forum realy helped me out a lot. I had no idea of how to size pipe or pumps, but it all works now!

By the way, the best insulated PEX supplier I found was http://www.badgerinsulatedpipe.com/ Nice people and by far less expensive than anybody else. $395 for 100' of 2x1" with 2x3/4" (four pipes wrapped together).

Also, make sure you get oxygen barrier PEX!!! NON OB PEX will rust out your boiler.

Good luck, I hope you have as much fun as I had!

-Don

Re: Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 9:54 pm
by windyhill4.2
I think its impossible to ask too many questions on here. I personally wish your 3 topics were all kept in 1 ongoing topic which for me makes it so much easier to follow & look back at earlier posts to refresh on different things, but that's just my opinion. I have not started any topic/thread yet,but later this yr when we hopefully switch to coal I will have to start posting our project. I'm sure some others will post their opinions soon & will be asking you lots of questions too.

Re: Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 10:02 pm
by Ted4
Hey windy, 3 topics? I'm confused. I just asked what size pipe. I'm lost. But open to suggestions. Btw,I'm a computer idiot, so if I'm doing it wrong, feel free to reprimand me, I have a thick skin.

Re: Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 10:12 pm
by windyhill4.2
I'm not saying you are doing it wrong,you have 1 on the trench/pipe issue ,1 on heat exchangers,1 on pipe size .I have never started a topic yet,maybe this is the preferred way,i was just saying I like a project to be ongoing as one topic but I might have a totally wrong concept of the way it is done.Just stated my personal preference which I guess shows my limited ability to follow things.Wasn't trying to confuse you at all :oops:

Re: Pipe Size From Boiler to House

Posted: Mon. Mar. 17, 2014 10:51 pm
by Ted4
I hear u, but when u have a continuos link and it gets played out, people lose interest. And if u introduce a new topic within the same thread, nobody will notice. That's my take on it. Whatever gets an answer ill try. U can buy books, but something's are better explained in Laymans terms.

Re: Pipe Size From Boiler to House

Posted: Tue. Mar. 18, 2014 6:16 am
by plumber
How many times do you want to do the job?

Your best bet is to make a loop to and from the boiler. Have that be a primary loop. Use 1 1/4 and a 0010 circulator. Have a pair of closely spaced tees in the house and take you house needs off the secondary.

Re: Pipe Size From Boiler to House

Posted: Tue. Mar. 18, 2014 6:56 am
by Sting
Ted4 wrote:Ok, another question for u pros. I have a Efm 350 that will sit in my coal shed 60 ft away. I'm ready to pull the trigger and buy the feed and return pipe. I have 3 zones in the house currently. Radiant in slab. 1/2" or 5/8 ID. not really sure. Should I go with 11/4" in trench, or 1"? The extra cost of bigger pipe is about 200.00 and probably a few hundred more between pipe and valves for larger size. The money really isn't the issue, I want to do it right. The question is, if I'm only pulling 3 zones with a total volume less than what a one inch pipe carries, is the bigger pipe overkill?
Leave all the expressed opinion at the curb and do the math!
Sizing is totally dependent on the [fault tolerant] flow in the correct pipe size to carry that load you want to heat. You could put a rocket engine on a straw and do the job or you can do it correctly - It depends!

There are some rules of thumb which have appeared in various threads. For heat transfer, maximum gpm: 1/2” - 1.5 gpm, 3/4” - 4 gpm, 1” - 8 gpm, 1-1/4” - 14-17 gpm, 1-1/2” - 22-25 gpm, 2” - 45-50 gpm.

One gallon per minute of flow (GPM) will move NO MORE THAN 10,000 BTU's of energy in a fault tolerant manor.

Re: Pipe Size From Boiler to House

Posted: Tue. Mar. 18, 2014 7:11 am
by windyhill4.2
Ted4,i reread your first post in this topic,you have an existing oil ? boiler in your house with 3 zones & it works ? how big are those circulators ? hooking your coal boiler to this set up is not going to change your current set-up,you will be heating your current boiler with the coal boiler water constantly circulating thru the current boiler.Current set up should help decide on pipe & circulator sizes as well as size of your house & BTU needed.A 1500 sq. ft. or less house will not need to have the more expensive pipe & valves/fittings that 1.25' will be.Check out what size was used in my earlier post & it works fine,ck. out Stokerdon & his Yellow Flame a Christmas project & see what he used.Bigger is not always better,bigger ciculators will result in a bigger unsatisfactory electric bill.I really think more info on your current set up will clarify the direction needed on your new project. According to the formulas that Sting posted our 1" with Taco 007 is providing less than 80,000 BTU & yet heats our house & the DHW for 2 houses, we are not using many BTU's :o

Re: Pipe Size From Boiler to House

Posted: Tue. Mar. 18, 2014 7:55 am
by Ted4
I made a big mistake when I built the house. It's 1900 sq on slab, 3 zones. I did not do my homework. I was young and dumb. I have one loop about 600 ft. I know, way too long. I live in Orange County ny. I burn about 700-750 gallons for the whole year. But my bedrooms at end of house are 62 degrees. I know that's not a calculated heat load, just some background. To be honest, the equations to calculate heat load look like Chinese to me. I'm in the architectural stone business and I can build my own diamond saws, but I can't make heads or tails of those equations.
I know I frustrated people a couple years ago when I was deciding what size boiler to buy because everybody was telling me to figure heat load. And u are all right. Maybe I'll have to get up bright and early say morning, have two cups of coffee and go at. I just figured I'd get a resounding, DEFINITELY USE 11/4", or, ONE INCH IS PLENTY. Guess I'm looking for easy way out. When I do steelwork or build a piece of machinery, I can look at a shaft or piece of steel, and just know it's going to be right size. I don't need to look at deflection charts or shear strenght. I just know it will work, based on my experience. I was just looking for easy way out with the plumbing. But maybe it doesn't work the same way, so I guess I'll get to work.
But just one question guys, going too small can be a problem. But can bring a little oversized be bad also?

Re: Pipe Size From Boiler to House

Posted: Tue. Mar. 18, 2014 8:18 am
by Ted4
Windyhill, I have 3 zones with taco 007 circs. The piping coming off the top of boiler is one inch going to my manifold. When I built my house, I was 27,28 years old and doing it as I could afford it. So some things were shortcuts. In addition, I have an overbearing father that was helping me with boiler. If u ever watched Orange County choppers, my old man makes Paul sr look like a kind gentle compassionate man. Get the drift? So some things were done with the"GOOD ENOUGH" mentality. Ok. Enough with the therapy session.
Yes my house can be comfortable, but I keep the bedrooms cold because of cost. When fuel was cheaper a few years back people were always bitching during holidays that my house was too hot. So yes it works. I did chop up the concrete to break the long loop in half, but never did it. I am aware that putting bigger pipe from coal shed to house isn't going to change the system in place. I totally understand that. I just didn't know if I should step up the pipe size coming to the house, because I've read a lot on here about guys saying to have those extra BTU on hand.

Re: Pipe Size From Boiler to House

Posted: Tue. Mar. 18, 2014 8:34 am
by Sting
Ted4 wrote: But just one question guys, going too small can be a problem. But can bring a little oversized be bad also?
It Depends!

This is not a yes or no question - these choices vs calculation will cause more pain [example under-sizing] but under-sizing isn't wrong when there is a back up to pick up the load on those special cold nights [ or when the kind folks at the emergency room invite you to spend a little more time with THEM] - but then I have been chastised it various threads suggesting that an undersized solid fuel boiler in concert with fault tolerant back- up heat source - is a good thing :shock:

in this case - if the dwelling already has a back up heat source - and your bringing in energy underground from and external coal fired appliance - then smaller may be better .

You see there are far FAR to many variables that you or WE have not discussed [ and I am not referring to the mouse in my pocket when I write WE]

Your best plan is to buy the books - take a few weeks and read them each four times - take notes - figure out what you need/want -

THEN start asking questions that can be answered yes and no - or left and right

TODAY - there is no silver bullet that anyone here can answer correctly [ I don't care if you beat your chest to say you have been doing this for 100 years] every install is different.

Kind Regards
Sting

Re: Pipe Size From Boiler to House

Posted: Tue. Mar. 18, 2014 8:45 am
by windyhill4.2
In your case 1.25"pex will not be that costly as you're only going 60',we have close to 1,000' of 1" so our cost would have been much higher going with bigger.You are only going from coal boiler to oil boiler so not many valves & fittings either. How big a circ you use will affect your electric bill as it will be running constantly. You are not alone in feeling lost with heat load calc,i did our system based on other peoples set ups that were working,not by any calculus charts. Since you have the concrete open you can improve by adding another zone,& even tho I went with 1" pex,i believe for your set up you would have better results with 1.25 " without drastically higher cost. On sizing the circ, you could install a 007,if it is not big enough you would then have a spare for the other zones,remember this loop will circulate constantly keeping the oil boiler water hot for any zone to pull from at any time. By the way if you look at Pa.pics you can get an idea of our set up as far as the buildings being served by the OWB. My motto is Keep It Sensible Simple,the money for those books & all the time spent studying them will cost more than going with the 1.25" & get the job done,just my .0000000000000000001