Outdoor Wood Furnace Info
All-Purpose OWF Discussions => General Outdoor Furnace Discussion => Topic started by: Clueless on April 02, 2014, 08:31:07 PM
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So we lit the wooddoctor, still not sure which model but we lit it, no leaks...i have a lot of questions, i hope i can keep them in order and i'm sure i will be on again with more.
I am only heating my 1500 square foot concrete slab in the basement.
We filled the boiler with hard well water, do i need to add citric acid, any clue how much?
There are 5 small flow meters on a header in the basement, they are only reading 1/8 to 1/4 gpm, almost at 0, is this normal? There are 5 loops from header to return. I changed the in floor ciculating pump, there was a lot of gunk on intake side and screen was nearly plugged on the outlet side, pump was also noisy. Changed it and flow increased a little bit. Nnow if there is gunk in the pump, house is 6 years old, can the floor runs be gunked up and can these be cleaned and whats the best way?
Set points on the boiler are 160 high limit and 140 low, make sense? The inlet on my header after mixing valve was at 110 degrees, and return in celcius was about 13 slowly climbing during the day, actually it only went up 3 deg celcius during 8 hours is this too slow? Whats the max temp for a concrete slab? Is it 140 deg? i played with the mixing valve but no noticeable changes, just happy its not seized.
Its a start, i really like the concept, havin fun learning but its tricky stuff...
Thanks everyone, i'm sure i will be back tomorrow with more, good night!
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Clueless, you have some serious issues, shut the pump off or you are going to kill it as well, it sounds like you will need to flush the entire system, can you send me a picture of your plumbing, I may be able to talk you through it.
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Yeah i shut the in floor loop, just the circulating pump for the boiler is on and makin a bit of noise i might add. I will leave it on i guess its still pretty cold here, there is awith small smoldering fire. I will take some pictures as soon as i go over no internet over there. But i will log on as soon as i can for directions.
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We will be looking for the purge ports and automatic water feeder, each loop will need to be purged of air and sludge separately with street pressure water, when you get there can you give me a call, I will need to be at the jobsite by 9 am, I'll PM you my number
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Did the purge, each loop one by one, a bit of gunk, not too bad, expected worse, new circulating pump, still 1/4 gpm flow, very low. Had no problem getting a good flow with city water through each loop..
The inlet temp stayed at 110 deg unless i played with mixing vallve, the return stayed at 55, then slowly rose to 60 deg in 10 hours, getting warmer but very slow, just trickling in. The only thing i can see is an obstructed mixing valve. Can't isolate it from boiler loop, gonna let it cool down and remove it, when weather warms a bit, still freezes at nigh here. The other pump used for the hot water tank seems to be running very well, lots of hot water. No issues there.
Any recommendations as to mixing vale brands or makes any options.
What would be the set points for the boiler fan on the boiler itself? Its at 140 low and 160 hi limit. Make sense?
How much water and how often does the average boiler require when in full use?
This stuff is addictive, i want to light that utility room with gauges and sensors, any ideas?
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Could we please go one step at a time, can you without voiding your warranty, turn up your wood boiler set point and start again, I would like to see 190+
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Will do. I'm working tomorrow but I will be back at the new house saturday and i'll fire it up and raise the set point to 190 - 200. See what happens.
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Will do. I'm working tomorrow but I will be back at the new house saturday and i'll fire it up and raise the set point to 190 - 200. See what happens.
Omg. This guy is awesome. Good luck clueless, let that fire roar.
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OMG was that a slam Victor, perhaps clueless and I have had conversations off forum!
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Ok like the name says, clueless, maybe not totally clueless, enough to get me in trouble i would say! So i apologize for any miscues...very interesting stuff...Anyways, no air issues that i can tell, the loops as i was told by the radiant installer should run at 1/4 gph, a little low for me but we now have that. I left it circulating tonight, should have good temp sometime tomorrow.
Are there any manuals for wood doctors, just to help me out and avoid any confusing or misunderstood questions. So far this has been the only place where with slimjim that i have been able to take stabs at the owb. I will load some pics of the boiler tomorrow, maybe you can nail the model from these pics.
Goodnight and thanks
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for starters i would set your delivery water to the floor at about 120 and open your flow to 1 gpm to each loop..i think (only think) your taco 7 (if it is just supplying the loops and you have another pump at the OWB) it should be able to supply between 1/2 and 3/4 gpm to 5 loops of 1/2 pipe 250 feet long
personally i think 1/4 gpm is not near enough
in my opinion i would like to see the flow about 1 gpm or a little higher but that would require a bigger pump than you have i think
if your loops are kept under the 300 foot maximum and your gpm is within the recomended flow charts, your return temps should be able to be kept 10 to 20 degrees below delivery temps. remember a .1 gpm increase = 5 btu per square foot
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Clueless, have no fear , we will get you there, nice post Willie, I agree!
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I agree the flow is low, the pump is new, in floor loops appear to be free of air/ debris. Boiler loop has also been purged, everything is flowing good. Now I only get 1 gpm on a loop when i isolate the 4 loops with one open, everytime and on each loop, no diference from one to another. Should i over the course of summer look into replacing the circulating pump with a bigger one? Woould there be issues with the boiler circulating pump if i was pulling more water into the floor loops? Now, How would i measure the flow in the boiler feed loop, would i have to install a flow meter, or iis there something easier?
Is it possible that there would be issues with the mixing valve like i mentioned before? It does regulate the temperature when i open/close it, seems to be doing its job. Debris ocstruction maybe?
I am over there all weekend i'm watching it every chance i get for temp/flow. No internet over there but i will keep posting here, if i get in trouble i'll make a call.
Thanks
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Do you still have my phone number? can you check your mixing valve for debris as well?
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for starters i would set your delivery water to the floor at about 120 and open your flow to 1 gpm to each loop..i think (only think) your taco 7 (if it is just supplying the loops and you have another pump at the OWB) it should be able to supply between 1/2 and 3/4 gpm to 5 loops of 1/2 pipe 250 feet long
personally i think 1/4 gpm is not near enough
in my opinion i would like to see the flow about 1 gpm or a little higher but that would require a bigger pump than you have i think
if your loops are kept under the 300 foot maximum and your gpm is within the recomended flow charts, your return temps should be able to be kept 10 to 20 degrees below delivery temps. remember a .1 gpm increase = 5 btu per square foot
Willie, been trying to understand the last part in red. If 1 gpm is good for 10,000 btu/hr , then .1 would be good for 1,000? (with 20 deg. D t) How do you figure 5 btu/sq.ft. increase? Each 1000 btu/hr for 1500 sq. ft. as in this case would be .666 btu/sq.ft.? I'm probably missing something, wouldn't be the first time. Also, that would be btu available, not necessarily what the floor would emit.
1/4 gpm in 5 loops would be 1-1/4 gpm so a possible 12,500 btu/hr. from the 1500 sq.ft. slab. (20 deg.Dt) Under slab insulation would be a big plus.
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for starters i would set your delivery water to the floor at about 120 and open your flow to 1 gpm to each loop..i think (only think) your taco 7 (if it is just supplying the loops and you have another pump at the OWB) it should be able to supply between 1/2 and 3/4 gpm to 5 loops of 1/2 pipe 250 feet long
personally i think 1/4 gpm is not near enough
in my opinion i would like to see the flow about 1 gpm or a little higher but that would require a bigger pump than you have i think
if your loops are kept under the 300 foot maximum and your gpm is within the recomended flow charts, your return temps should be able to be kept 10 to 20 degrees below delivery temps. remember a .1 gpm increase = 5 btu per square foot
Willie, been trying to understand the last part in red. If 1 gpm is good for 10,000 btu/hr , then .1 would be good for 1,000? (with 20 deg. D t) How do you figure 5 btu/sq.ft. increase? Each 1000 btu/hr for 1500 sq. ft. as in this case would be .666 btu/sq.ft.? I'm probably missing something, wouldn't be the first time. Also, that would be btu available, not necessarily what the floor would emit.
1/4 gpm in 5 loops would be 1-1/4 gpm so a possible 12,500 btu/hr. from the 1500 sq.ft. slab. (20 deg.Dt) Under slab insulation would be a big plus.
the initial output would not be figured at 10,000 btu/hr as the inlet temp to the floor heat loops would only start at 120 degres and not 180...therefor output is quite a bit less
at 1/4 gpm in the 1/2 inch pex you would be moving only about 40 fpm it would take almost 6 min for the water to travel the length of a 250 foot loop.. that is why return temps are so low and btu output is low you have to move the water a little faster to get to your desired 20 degree delta
i am running my loop in my basement at the max for 1/2 pex and i think i am very clsoe to 2 gpm with an entering temp of 120...my loop is 250 feet long and my return temp is 110. my loop is 2 inches below the top of the slab and i have 2 inches of foam under the slab.
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Thank you Willie, I sure wish I could do math the way you guys can, How about teaching me how to post pictures?
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Slim i havent posted a photo in a long time on this board. i used to just open my photo in a program such as as "paint" and shrink it to about 30 percent of original size and the site would allow me to post. (most sites like this have a maximum file size to try and keep room available)
or you can post yoru photos to a storage site such as "photobucket" and then paste and copy a link in your message to take the viewer directly to your photo (s)
http://i67.photobucket.com/albums/h308/billie_boy7/silvers%20replacement/012-1.jpg (http://i67.photobucket.com/albums/h308/billie_boy7/silvers%20replacement/012-1.jpg)
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I'm going to have to see it done, I'm just hillbilly enough to not understand what you are talking about, Scott can explain as he already tried with me, Sorry.
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ok lets see what happens..if my post goes i will send you a pm on how it is done step by step
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That worked Willie, next step is to teach me how to do it!
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Clueless, I hope you are getting some heat out of your slab by now. I was thinking you have additional radiant heat capabilities in your house but are just concentrating on the basement first? You have an 007 for your basement slab, a ?? at your boiler? and what other pumps if any and what size? Is there insulation under your floor slab, or basement walls? Also, can the installer you mentioned tell you anything more about your installation? This information can help the pro's advise you, I'm no pro, just trying to learn here.
Willie, I'm math challenged so having been forcing myself to figure some of this stuff out.
The only clues from Clueless were 5 loops at .25 gpm, a supply temp of 110, return temp 60. Thats a Dt of 60. So 1.25 gpm x 500 x 60Dt= 31,250 btu/hr. (assuming 5 loops at 1/4 gpm) You said output would not be 10,000btu because water was not 180. Nobody would send 180 into a slab, but if so, btu output would still be gpm x 500 x Dt=btu/hr. As the slab temp. approaches the air temp, the Dt would narrow, then at some point, you would only need to supply enough btu to cover the heat loss and maintain the desired room temperature.
Also,I still don't understand the statement "a .1 gpm increase=5 btu per sq. ft." Is that some sort of rule of thumb? To me it seems like something that could occur but other factors like how many square feet, spacing of pex in slab, slab insulation, would all influence btu/sq ft. In your own basement, (2 gpm, Dt 10 deg) you would be supplying btu's at the rate of 10,000 btu/hr. If you increased you gpm to 2.1( and your Dt remained the same) your out put went up to 10,500. If there was a 5 btu/sq.ft increase, your basement is 100 sq.ft.Any thoughts? I know I'm missing something here. Please help, my wife just gives me a blank stare when I bounce this stuff off her.
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Clueless, I hope you are getting some heat out of your slab by now. I was thinking you have additional radiant heat capabilities in your house but are just concentrating on the basement first? You have an 007 for your basement slab, a ?? at your boiler? and what other pumps if any and what size? Is there insulation under your floor slab, or basement walls? Also, can the installer you mentioned tell you anything more about your installation? This information can help the pro's advise you, I'm no pro, just trying to learn here.
Willie, I'm math challenged so having been forcing myself to figure some of this stuff out.
The only clues from Clueless were 5 loops at .25 gpm, a supply temp of 110, return temp 60. Thats a Dt of 60. So 1.25 gpm x 500 x 60Dt= 31,250 btu/hr. (assuming 5 loops at 1/4 gpm) You said output would not be 10,000btu because water was not 180. Nobody would send 180 into a slab, but if so, btu output would still be gpm x 500 x Dt=btu/hr. As the slab temp. approaches the air temp, the Dt would narrow, then at some point, you would only need to supply enough btu to cover the heat loss and maintain the desired room temperature.
Also,I still don't understand the statement "a .1 gpm increase=5 btu per sq. ft." Is that some sort of rule of thumb? To me it seems like something that could occur but other factors like how many square feet, spacing of pex in slab, slab insulation, would all influence btu/sq ft. In your own basement, (2 gpm, Dt 10 deg) you would be supplying btu's at the rate of 10,000 btu/hr. If you increased you gpm to 2.1( and your Dt remained the same) your out put went up to 10,500. If there was a 5 btu/sq.ft increase, your basement is 100 sq.ft.Any thoughts? I know I'm missing something here. Please help, my wife just gives me a blank stare when I bounce this stuff off her.
Haha, my wife does the same but this math stuff I am sure I have the same look ???
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For high mass slabs when used for heating, a 10 degree DT is recommended for even floor temp. Depending how it's piped and what the Cv value is for the mixing valve, the 007 is probably shy even at DT20. If the 007 is right on the mani and a low loss MV , Its 10' head@ 1 GPM @ 120* and 3.5' @ .5gpm. It's ok if its idled or you don't expect a quick recovery time. You can see what it does by closing 3 loops and testing DT from there. Sounds like some fine tuning. I run as low as 90*, but insul and soil conditions play a very big role. And as high as 140 if the flat men didn't do a good job on the mesh chairs. I'd rather see increased flow before higher temp if possible.
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here is a shot of my single floor loop and its circulating system
pump is pushing water down..top left is return from floor..bottom left is feed into floor..top right is hot OWB water in and bottom right is return to OWB
after checking on the little pump i find it is running between 1.5 and less than 2 gpm
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Willie, what's the zone valve about?
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Also wondering about the zone valve. If it closes, does the rest of your system get increased flow? And would the water still continue to circulate in your floor loop?
Thats a cool use of a Watts M-series Isotherm kit. Apparently the new setups are the same in stainless.
( just searched and the Isotherm is the same, the manifolds are in stainless)
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lets see if i can explain...the zone valve is controlled by the wall thermostat...when the room is satisfied the circulator circulates through the zone...this ensures a pretty much even temp through out the floor as the water is always moving so there are no "cold" spots. the pump is punshing down so the water is coming from the top left pipe (out from floor) and ging back in the bottom left (into floor) when the room calls for heat the zone valve opens and now water that is being pulled from teh floor loop is pushed down and at the same time some new water is added from the OWB line, this water is mixed with some of the cooler floor water by it being pushed (and/or sucked) up the "cold: inlet in the mixing valve. what ever comes out of the floorloop MUST go back in and floor water that was replaced with hot water from the OWB feedl ine now goes out the zone valve and back to the OWB
i hope this kind of makes sense..i may not be real good at describing it but it works :thumbup:
as for increased flow..i guess so...i have a manifold in the house that is fed from my taco 11 and it services this floor loop, the water to air exchanger in teh furnace and a small rad in my fire place and the home made tube and shell for the doemstic...the domestic (3/4 copper) and the fireplace water to air (1/2 pex) are both circulating 24/7 so is uspect when the floor loop kicks in those things sufffer the loss while the floor loop is running..i have never seen any downfall from this
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Yeah the slab is good and warm, took a while. Inlet at 110 -120, outlet at 70 (ambiant room temp). I'll be shutting it down soon, and this summer gonna tackle the mixing valve. I will also get in touch with the people who did the install, should be some documents or prints.
Now for the summer, should i drain it? Leave it full? Any tips on summer mode would be of great help. Thanks again for your input...i also have some treatment for the water, whats the ratio?
Cheers!
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Sample water sent to corporate for testing and don't drain it
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Yeah the slab is good and warm, took a while. Inlet at 110 -120, outlet at 70 (ambiant room temp). I'll be shutting it down soon, and this summer gonna tackle the mixing valve. I will also get in touch with the people who did the install, should be some documents or prints.
Now for the summer, should i drain it? Leave it full? Any tips on summer mode would be of great help. Thanks again for your input...i also have some treatment for the water, whats the ratio?
Cheers!
Whenever you drain, the air that enters immediately starts corrosion or breaking down any treatment. It also would be a good idea to cycle the circs once a week for a few minutes, or atleast once a month.