I need help and advice on new coal/wood boiler putchase

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Jimmyfunk60

New Member
Jul 10, 2017
5
Dellroy, Ohio
Hello all first time poster... In the process of selecting the right wood boiler for my needs. Was really interested in the woodmaster 5500 or in a central boiler classic. However the central boiler forge 3500 really caught my attention. I have access to coal locally at a reasonable price. I also have access to wood at my house. I understand that new EPA regulations stamp coal burners as coal only. When I called central they said you can not burn wood in these units as it will damage or burn out the grates? In my mind coal would be a much hotter fire on the grates than wood. I was planning on purchasing this unit and burning a mixture of wood and coal... Coal is appealing for when I get super busy and don't have time to get wood in, it's also seems like it would be a little more convient for the Mrs. or if we were out of town for my dad or neighbor to fill. Looking to hear any of your guys experiences or thoughts.

I will be heating a 2600 square foot house with finished 1500 square foot basement 12 years old with good insulation 2x6 walls blown in in attic but high ceilings and a lot of Anderson windows ( currently have a 115,000 btu propane forced air furnace and heat pump) hot water, 40x60x14 shop, and a pool in future. Wood boiler will be near my shop so it will be a 300 foot run to house and 20 foot to shop.
I am also in North East Ohio for climate and weather.

I cant justify heating with propane any longer especially with brining the new shop online. I went through roughly 1400 gallons of propane on just the house last year with a 93% efficient furnace.
 
How well insulated is the existing 300 foot run? What size pipe is it? What is the total heat load calculated to be? I'm thinking that you would need around 55,000 BTUH? possibly 65,000. But a lot depends on the losses in such a long run. Is there a reason you would not consider locating a boiler in the house?
 
Run will be 300' of thermopex 1" line don't want a boiler in house, and will still have that run to heat my shop. Current furnace is 125k btu.. and I'll be adding hot water and 40x60 shop on heat load
 
This doesn't deal with your boiler questions - but have you done head loss & flow calcs on that 300' run? Are you sure you can get the BTUs through it you need - and do you know what you will need for a pump if so?

I don't think I would go less than 1-1/4", personally - said without running any numbers.

It's the one thing to get right and most often not considered seriously enough - since it's pretty hard to do over and expensive also. And burying pipe is usually one of the first things people do - sometimes with later regrets.
 
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This doesn't deal with your boiler questions - but have you done head loss & flow calcs on that 300' run? Are you sure you can get the BTUs through it you need - and do you know what you will need for a pump if so?

I don't think I would go less than 1-1/4", personally - said without running any numbers.

It's the one thing to get right and most often not considered seriously enough - since it's pretty hard to do over and expensive also. And burying pipe is usually one of the first things people do - sometimes with later regrets.

You bring up a very good point and I guess I need to find someone to run calculations for me. I'm looking to be about 270' from boiler to house foundation. This is a slight grade drop of 2-3 foot then into my basement and back to the boiler. The dealer told me 1" line and a taco 009 pump should meet my demand. I was thinking a 150k btu exchanger. I also want to use a side arm on my water heater can I just jumper off my one inch lines or does that take a separate set? The plumbing side of this thing has now got confusing.
 
A year or two I could have run some stuff off the top of my head - now it would take some digging. Maybe someone will be along to run some quick numbers - sooner or later.
 
Well if you give me your goal of btu/hr (Q) we'll assume a 30*F temp drop across supply to return in the house (energy left in the house). I'd assume 1 1/4" pex, it will pay for itself in electricity savings over time (lower flow rate means smaller pump). And guess the # of ells, tees, ball valves distance boiler to house... and I'll compute a quick equivalent piping length which will give you a head loss start. The btus/hr and deltaT will tell you how much gpm you need.

I'll plug this into the spreadsheet I made of the Taco TD10 pump sizing doc. No guarantee but its a start point and its free.

With gpm and required head loss you go to the TACO pump table and Voila. This will get you very close in the ballpark. Cheers

BTW, my system has 10 ells, 12 tees, and probably 10 ball valves for a fairly typical 340' loop barn to house and back. (170' one way)

Ok... back to boring work.

Oh... you wanna know about good boilers. Look in the signature blocks of long time posters with LOTS of posts. (Maple for example) That's your key to a happy operator. Lots of them here. But us old guys seem to be scarcer now a days. Cheers again.
 
Well if you give me your goal of btu/hr (Q) we'll assume a 30*F temp drop across supply to return in the house (energy left in the house). I'd assume 1 1/4" pex, it will pay for itself in electricity savings over time (lower flow rate means smaller pump). And guess the # of ells, tees, ball valves distance boiler to house... and I'll compute a quick equivalent piping length which will give you a head loss start. The btus/hr and deltaT will tell you how much gpm you need.

I'll plug this into the spreadsheet I made of the Taco TD10 pump sizing doc. No guarantee but its a start point and its free.

With gpm and required head loss you go to the TACO pump table and Voila. This will get you very close in the ballpark. Cheers

BTW, my system has 10 ells, 12 tees, and probably 10 ball valves for a fairly typical 340' loop barn to house and back. (170' one way)

Ok... back to boring work.

Oh... you wanna know about good boilers. Look in the signature blocks of long time posters with LOTS of posts. (Maple for example) That's your key to a happy operator. Lots of them here. But us old guys seem to be scarcer now a days. Cheers again.


I'm not sure in btu I figured I have a 125k furnace now so 150k btu exchanger? Plus what ever water heater will take for the side arm. I had t really thought about what all fittings I needed. Assuming straight shot from tie in on boiler to house, some type of header with a jumper to hot water tank one to furnace then another header back to the outlet. Will prolly want ball valves on suction and discharge idk how many tees I will get Into I was priced 1" thermoplex at $9.50 a foot idk what 1-1/4 runs

Can you get me in a ball park on these figures or need more info? Am I barking up the right tree with my thoughts on exchanger?
 
My only input comes from switching over to coal from wood in my New Yorker "wood/coal boiler"... It works, after some tinkering and some grate redesigning, but it seems like you'd want specifically a wood boiler, or a coal boiler... Wood and coal fires have different needs, and it doesn't seem like a boiler designed for "both" is truly ideal at both.... That said, I'm very happy with burning coal, and wouldn't go back to firewood.
 
My only input comes from switching over to coal from wood in my New Yorker "wood/coal boiler"... It works, after some tinkering and some grate redesigning, but it seems like you'd want specifically a wood boiler, or a coal boiler... Wood and coal fires have different needs, and it doesn't seem like a boiler designed for "both" is truly ideal at both.... That said, I'm very happy with burning coal, and wouldn't go back to firewood.
Central forge 3500 is designed and stamped strictly for coal... I have heard of guys half banking with coal and topping off with wood. I also talked to someone that ran straight wood all year until the deep cold set in then they burned coal
 
150k btu/hr System:
Assuming you need to dump 150K btu/hr into your house and you design/size your HX or radiant to dump 30*F (return 30* lower than supply).
This requires 10 gpm, flowing in 1" pex with .875 I.D. your flow velocity is 5.33 fps (feet/sec). The recommended velocity is 2-4 fps. If you use 1 1/4" pex (1.054 I.D) the velocity drops to 3.7 fps.... better.

Head loss for this 150k assumption and 1" pex is 15'.
Head loss for this 150k assumption and 1 1/4" pex is 5.4'.


100k btu/hr System:
Assuming you need to dump 100K btu/hr into your house and you design/size your HX or radiant to dump 30*F (return 30* lower than supply).
To do these assumptions requires 6.7 gpm, flowing in 1" pex with .875 I.D. your flow velocity is 3.6 fps (feet/sec). The recommended velocity is 2-4 fps. If you use 1 1/4" pex (1.054 I.D) the velocity drops to 2.5 fps.... better.

Head loss for this 100k assumption and 1" pex is 10'.
Head loss for this 100k assumption and 1 1/4" pex is 4.5'.

Now you can kinda get in the ballpark on circ pump size. looks like an 009 is a start point.

SO.... big deal to really know how many btus you need to heat your house. Given your length of run which is similar to mine 1 1/4" seems the right choice with either sized system. If you plan storage, HIGHLY RECOMMENDED, oversizing the boiler has little penalty. I'm a strong advocate of the boiler in the barn far away. Less efficient but momma will be happier with the dirt outside. Others love in house.... great. Never in my home. Ok, gotta go make money. Been fun to dust the cobwebs off on this stuff.
 
So much depends on whether your burning anthracite or bituminous coal which are two very different animals and burn quite differently.

The other thing is the needed chimney height as well as the coal size.

You need to provide much more information and you cannot skimp on pex pipe as you will need logostor pex but for the money you can buy steel pipe and bury it with foamed insulation in forty foot pipe joint lengths.

For the work you intend on doing you would be better off buying an EFM DF520 coal stoker boiler that can burn both bituminous and anthracite rice coal and install it in your shop to heat everything with it and not worry about heating your domestic water because you need a lot more plumbing. ($9500.00)

An AHS 260 stoker or the EFM DF520 coal stoker would be more than adequate for your needs.


If someone tells you you cannot burn wood in a coal boiler walk away from that brand or dealer!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


Your planning on spending a huge wad of money already with buried pex at 15 dollars a foot($4500.00)
if you bought steel pipe you would need 9 40-foot joints, a rental pipe threader and pipe cutter, pipe couplers, elbows and teflon pipe dope and white teflon tape. after you put sand in the trench you can set the foam and the pipe and your done as a pressure test was done for 40 hours at 60 PSI water pressure to be sure the joints are tight and do not leak.


Before you get any further you need to look at a Garn or a Switzer wood boiler with storage as you may be looking at 20K or more by the time you price a lot of material if you want to burn wood. I got away
from wood after 33 years of burning it and I have a keystoker dual fuel unit


You need to do a lot of work and create a decision tree to start this as well as having a heat loss study done as the very first item.
 
My newly built shop has 1800 feet of radiant tubing in the slab. It is not being used. Why you ask? The wood/pellet boiler and "required accessories" are very very expensive. So much so that spending a few thousand for proper insulated pex is a drop in the enormous bucket. I hope you know what you're getting into.
 
I don't think I would recommend that underground piping idea.
You couldn't pay me enough to build that underground piping for myself,and i would never build underground piping like that for anyone else...well maybe for that guy that i hate,then i could watch him work his A$$ off living with that piping.
 
Amazing how great the advice here is. So I will chime in, hoping it all helps in some small way. The presumed delta of 30 degrees, from my experience, is greater than most homes "provide" to the heat generation appliance. This single assumption could require your flow to be significantly higher than you may be counting on. Stay with 1.25 inch minimum for a run of this length. And still, every minute of every hour of every day, the losses are there. Always adding up and up and up. Put the boiler inside the envelope of the greatest and most constant load. Or darned close to that load. With all of this advice I wish you well!
150k btu/hr System:
Assuming you need to dump 150K btu/hr into your house and you design/size your HX or radiant to dump 30*F (return 30* lower than supply).
This requires 10 gpm, flowing in 1" pex with .875 I.D. your flow velocity is 5.33 fps (feet/sec). The recommended velocity is 2-4 fps. If you use 1 1/4" pex (1.054 I.D) the velocity drops to 3.7 fps.... better.

Head loss for this 150k assumption and 1" pex is 15'.
Head loss for this 150k assumption and 1 1/4" pex is 5.4'.


100k btu/hr System:
Assuming you need to dump 100K btu/hr into your house and you design/size your HX or radiant to dump 30*F (return 30* lower than supply).
To do these assumptions requires 6.7 gpm, flowing in 1" pex with .875 I.D. your flow velocity is 3.6 fps (feet/sec). The recommended velocity is 2-4 fps. If you use 1 1/4" pex (1.054 I.D) the velocity drops to 2.5 fps.... better.

Head loss for this 100k assumption and 1" pex is 10'.
Head loss for this 100k assumption and 1 1/4" pex is 4.5'.

Now you can kinda get in the ballpark on circ pump size. looks like an 009 is a start point.

SO.... big deal to really know how many btus you need to heat your house. Given your length of run which is similar to mine 1 1/4" seems the right choice with either sized system. If you plan storage, HIGHLY RECOMMENDED, oversizing the boiler has little penalty. I'm a strong advocate of the boiler in the barn far away. Less efficient but momma will be happier with the dirt outside. Others love in house.... great. Never in my home. Ok, gotta go make money. Been fun to dust the cobwebs off on this stuff.
 
They bury steel pipelines every day.

Pushing 4-8 psi through 3/4 black iron pipe that is surrounded with foamed in place insulation would not be an issue as long as its installed correctly and secured B4 its foamed in place.

Until he prices every thing he will not get the rude awakening that he is spending a lot more money than he needs to.

The smallest AHS S130 anthracite coal stoker ($7000.00) will fit nicely where ever he puts it with just a few pipe tappings and using a 30 or 60 gallon steel expansion tank will let him heat everything with 4-8 PSIG.

Coal stoker stoker boilers come with circular copper coils installed and are offered as standard equipment so building a side arm plumbing arrangement is not needed where all you need is a mixing valve from a cold water source.

.
 
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Knock... Knock... Jimmy... Did we waste our time?
 
They bury steel pipelines every day

Apples and oranges
Steel pipelines are welded,covered with a protective layer of plastic/rubber/vinal,and are not carrying heat for heating purpose.That is the case for the majority of the pipelines i think you are referring to.
Having that many threaded joins underground is like playing Russian roulette.
 
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The spirovent that is in his system has to be removed as that is the root of his heating issues.

Not really apples and oranges nor are threaded joints problematic as long as they are tested for at least 8 hours at 60 PSI cold.

Threre are lots of copper soldered joints that are used in low pressure steam just like there are threaded schedule 80 pipe and couplers used for steam and gravity hot water heating systems.


There are lots of water wells with threaded steel pipe in the ground used for delivering potable water that also have 4-6 inch threaded well casing and couplers.

Hot and cold pex loops are and can be foamed in place where the end user contracts to have a trench foamed in after the tubing is placed and secured in a trench as the owner does not want to spend the money on closed cell foam carrying a hot and cold pex pipe pair.

As I said the over sized steel expansion tank used for expansion will let him use very low pressure hot water from 4-8 PSI to heat everything so......
 
My newly built shop has 1800 feet of radiant tubing in the slab. It is not being used. Why you ask? The wood/pellet boiler and "required accessories" are very very expensive. So much so that spending a few thousand for proper insulated pex is a drop in the enormous bucket. I hope you know what you're getting into.

A good friend plus a former workmate both used a standard hot water heater for their detached garage/shop slab heat. Yes the parts are expensive to do it right from the ridged foam board under the slab and the tubing but I'd be damned if I let it all go to waste.

You couldn't give me the absolute best outdoor boiler for free.
 
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The spirovent that is in his system has to be removed as that is the root of his heating issues.

Not really apples and oranges nor are threaded joints problematic as long as they are tested for at least 8 hours at 60 PSI cold.

Threre are lots of copper soldered joints that are used in low pressure steam just like there are threaded schedule 80 pipe and couplers used for steam and gravity hot water heating systems.


There are lots of water wells with threaded steel pipe in the ground used for delivering potable water that also have 4-6 inch threaded well casing and couplers.

Hot and cold pex loops are and can be foamed in place where the end user contracts to have a trench foamed in after the tubing is placed and secured in a trench as the owner does not want to spend the money on closed cell foam carrying a hot and cold pex pipe pair.

As I said the over sized steel expansion tank used for expansion will let him use very low pressure hot water from 4-8 PSI to heat everything so......


Why are you talking about spirovents- and what problems? This is something being planned, no problems to report yet, and don't think anyone mentioned vents.

Excuse me while I jump back to the top to see if I missed something...