Trouble heating with AHS WOC55

I've been trying for the past two winters to get this boiler to work for me with little luck. It sits out in my garage about 70' from the house, which is about 2500sq ft. I have two supply and return runs, 1.25 pex al pex. They are connected into the 2" pipes in the basement on the opposite end from the oil boiler which I have isolated. The problem I am having is keeping the boiler up to temp. I tried using a boiler bypass but the lower system temps would not heat the house so I put in a system bypass and now seem to have lost some flow which is what I expected to happen but with the pump I have didn't think would be much of a problem(taco 2400-50). So I wonder if the boiler is big enough or I just don't know what I'm doing.

i can tell you the there will be some people along at some point that can give you a lot more help than i can. But they will want some more information. Things like boiler makes, model numbers, rated outputs, what you are heating ie. baseboard, radiators, etc. how much/many of these you have. details about your house. layout, insulation, quality of construction etc. what water temps are you trying to reach? are you having trouble reaching these temps at the oil boiler or the coal boiler? what temps are you reaching? what type of coal are you burning? who is your supplier? have you completed a heat loss calculation of.any kind?

and pictures never hurt! lots and lots of pics.

Please explain what is connect to the boiler in detail. How did you heat the house before the AHS? What are you burning in it?

I have a woc55 also. Before anything we need to know if you have boiler problems,circulation problems or heat loss problems,supply and return pex heat loss from ground saturation.
Boots ans Robs questions will be helpfull to solve the problems

with the boiler,what are your aquastats set at and is the boiler turning on and off at desired settings.Do you have hot water going into the return water(not sure what the techinal term for that valve is).
Are the brick baffles clean from fly ash

Dennis wrote:Do you have hot water going into the return water(not sure what the techinal term for that valve is)

i think its called a tempering or mixing valve.

Blower turns on at 170 and off at 180 dumps at 200.

This is the third winter that I have lived in this house. The first winter we went through about 1200 gallons of heating oil and that convinced my wife to let me get a coal boiler. The house was built in the mid to late 1800's. It is a two story house with an attached garage and a living room addition both added on in the 1950's. All of the windows are newer maybe late 90's and we had it insulated this fall with foam injected into the walls and spray foam in the attics. There is a combination of cast iron radiators and fin tubes. The fin tubes don't put out much heat at all which is a problem because there is about 30' of them on the first floor.

The boiler system is a two pipe system with 2" mains and 1" pipe going to the radiators and 3/4" fin tubes. When I tied in the AHS I ran 1 1/4" to both supply and return on either side of the basement then just closed the valves at the oil boiler to take it out of the loop. The underground pex is in closed cell foam and wrapped in radiant barrier foil then shoved and I mean shoved in 6" pvc sewer pipe. I do know for a fact that I am losing about 15* under ground, and I notice now that we got some snow that it is melting over the ditch. But even with the heat loss in the ground it is still about 25* drop over all and when the house calls for heat the boiler drops to less than 130* in just a few minutes sometime it will work its way back up to around 150* but I would think it would raise higher than that. I have also checked the draft with a manometer at idle it is -.04 but when the fan kicks on it is well over -.2 or -.3 and yes I do have a baro damper about 2' from the outlet on the boiler. Am I losing all the heat up the chimney? Haven't checked stack temp.

I am burning bit coal that I get from a local power plant, I got a friend that can get it for free! I have never burned coal before so I don't really know it is good coal or not. I can tell you that I get a lot of ashes, I empty the pan sometimes twice a day, but I do burn a lot of coal maybe a wheel barrow load a day.

It sounds like you have serious heat loss underground, a lot of mass in the house heating system, and possibly poor quality coal.

By the way, if that fin tube is connected to an old branched main via monoflow tee's or such, there is probably too much resistance through the fin tube to get any flow (easier to bypass at the main then go through all that fun tube).

wow, you are burning a pile of coal. do you have any idea how many pounds you fit in a wheel barrow? I for sure am no expert but i agree with Rob, it sounds like you have a lot of metal to heat up when your house calls for heat. and maybe your coal quality is not the best.add all of that to the fact that you are loosing 15° before the water even makes it into your home and you have your answer. how many btu' s is your oil boiler rated at? did it heat the home well?

porter06 wrote: I have also checked the draft with a manometer at idle it is -.04 but when the fan kicks on it is well over -.2 or -.3 and yes I do have a baro damper about 2' from the outlet on the boiler. Am I losing all the heat up the chimney? Haven't checked stack temp.

I have my mano set at .03 and when the combustion blower turns on it stays at.03. Adjust the baro after the fire is burning hot.I believe your loosing heat up the chimney,is the baro plate clean

porter06 wrote:I am burning bit coal that I get from a local power plant, I got a friend that can get it for free! I have never burned coal before so I don't really know it is good coal or not. I can tell you that I get a lot of ashes, I empty the pan sometimes twice a day, but I do burn a lot of coal maybe a wheel barrow load a day.

I believe when you burn bit coal you don't use the combustion blower(get too many clinkers) only natural draft and over fire draft. Do you have the "soft coal linkage" hooked up to the lower ash pan door for natural draft
I only burn ant coal, so you need to ask or search in the bit. section
When burning coal try to open the grates slightly to allow more air flow the the coal bed
I just looked at the manual and it's not that helpful or informative,you need to do a search on burning bit. coal
I don't know too much on the plumbing end of the boiler but learning,Rob R. is the expert when it come to the plumbing and circulation parts.

porter06 wrote: am burning bit coal that I get from a local power plant, I got a friend that can get it for free! I have never burned coal before so I don't really know it is good coal or not. I can tell you that I get a lot of ashes, I empty the pan sometimes twice a day, but I do burn a lot of coal maybe a wheel barrow load a day.

What size is the coal.From what the bit. burners say you need lump coal sizes from baseballs to softball and volley balls.You may not be getting enough air thru the coal bed to bring the boiler temps up quicker to satisfy the heat load

Woooaaaaaaaa! Hold the phone. You get a 15 degree drop in temp from one end to another in 60' of pex. Hellooooooo! Finger tapping on the head. If I'm figuring that right, with the flow rates from the pump size and the pex sizes, that's almost 150 K BTU losses into the ground. How can that be??????? No wonder you are having problems. Do you know why the ground heat loss??? That seems like a lot.

Melting snow over the pipes is a serious red flag!

You have insulation failure. Possible water in the pipes. You have a snow melt system, not a house heating system.

Shoving it hard through the sewer pipe probably ripped off some of the insulation.

You will need to rework that system. Need to make sure you can drain water out of the underground pipe. Are the joints solvent welded?

Also, the coal from the power plant... Do you know where it comes from? Could it be from the Powder River Basin brought in by train? This coal is lignite and is very low in btu's per lb.

steamup wrote:Also, the coal from the power plant... Do you know where it comes from? Could it be from the Powder River Basin brought in by train? This coal is lignite and is very low in btu's per lb.

This place never ceases to amaze me. Members here are very knowledgeable. Some of the facts thrown around this place are mindblowing.

Rob R. wrote: how many btu' s is your oil boiler rated at? did it heat the home well?

Oil boiler is 181,000 Weil Mclain, it did ok. I figure it would do better if I could get more flow through the fin tubes.

Boots wrote:I believe when you burn bit coal you don't use the combustion blower(get too many clinkers) only natural draft and over fire draft. Do you have the "soft coal linkage" hooked up to the lower ash pan door for natural draft

No natural draft door. I did in fact pay for a soft coal linkage kit and that is what I was expecting to get, but when I called AHS I was told that the combustion blower is what I needed. I will be on the phone with them this week.

Dennis wrote:What size is the coal.From what the bit. burners say you need lump coal sizes from baseballs to softball and volley balls.You may not be getting enough air thru the coal bed to bring the boiler temps up quicker to satisfy the heat load

The coal is nut size, I will try some lump coal.

steamup wrote:You have insulation failure. Possible water in the pipes. You have a snow melt system, not a house heating system.

I was worried about that when I was putting the pipe together. I thought I was in the clear after the first time it rained and there wasn't any water running into the basement, didn't give much thought to any insulation being ripped off of the pipe. Looks like I'll be digging up the yard again.

steamup wrote:Also, the coal from the power plant... Do you know where it comes from? Could it be from the Powder River Basin brought in by train? This coal is lignite and is very low in btu's per lb.

The coal is brought in on barges it's mostly from SWPA and WV.

This place never ceases to amaze me. Members here are very knowledgeable. Some of the facts thrown around this place are mindblowing.[/quote]

I agree, wish I would have found this forum sooner and spent more time reading rather than trial and error. Thank you for all of the advice and I will keep you all updated on any future progress.