Outdoor Wood Furnace Info

All-Purpose OWF Discussions => General Outdoor Furnace Discussion => Topic started by: johnybcold on January 24, 2013, 01:57:42 PM

Title: OWF reads 188 but inside boiler temp never goes over 170?
Post by: johnybcold on January 24, 2013, 01:57:42 PM
I have a CB1400 my piping is about 70-80 feet with 3 90 degree elbows on each line, these feed into my oil boiler un pressurized ( no plate exchanger) the gauge on my indoor boiler never goes over 170, when I ran it on oil it would go over 200, do I need to burry my pipe deeper I used the CB insulted pex most of it is around 2-3 feet deep with I few spots only 8" deep, or could it be I need a bigger pump I am using a taco 007
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: willieG on January 24, 2013, 03:36:25 PM
you can not expect the outdoor boiler to heat your indoor boiler to any higher than what your outdoor boiler's highest setting is (likely a little lower) if you have your OWB set to shut off with a high temp of 180 i would make a guess that your indoor water temps would never exceed 175 your pump size will depend on the length of your underground pipe's and their size and all the piping in your loop counting elbows and such...the depth at wwhich your pipes is burried has nothingn to do with anything (unless your pipes are so deep they are laying in water. the insulation of your underground pipes is important. My self, i believe the underground pipes you choose are just as (if not more than) important than the  OWB you choose
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: Trint on January 24, 2013, 03:42:20 PM
Have a similar setup to you only 35 ft of pipe though, wood boiler is set to 185 and boiler gauge rarly goes over 165-170 untill the zone circulator shuts off.  I have the 3 speed taco OOR though, tried a 007 at first but it wasn't enough(worked on paper).  If you house stays warm I wouldn't worry about it, the lines don't need to be deeper mine are 2' and come out the ground into the house and don't melt the snow.  They are the foam filled type.
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: Scott7m on January 24, 2013, 03:42:38 PM
you can not expect the outdoor boiler to heat your indoor boiler to any higher than what your outdoor boiler's highest setting is (likely a little lower) if you have your OWB set to shut off with a high temp of 180 i would make a guess that your indoor water temps would never exceed 175 your pump size will depend on the length of your underground pipe's and their size and all the piping in your loop counting elbows and such...the depth at wwhich your pipes is burried has nothingn to do with anything (unless your pipes are so deep they are laying in water. the insulation of your underground pipes is important. My self, i believe the underground pipes you choose are just as (if not more than) important than the  OWB you choose

Yea all true, deeper is hardly ever better.  Once the hest escapes the package, it's gone.  No matter what you lose it too.  If you get down into wet and mucky, that's not good at all
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: MattyNH on January 24, 2013, 07:22:18 PM
Boy thats a good question.. For me I don't have a problem..What ever temp reads on my owb is what my oil boiler reads..Im 90ft back from my house then another 28ft to my oil boiler..Running a taco 007 pump...Now my buddy exact same boiler..He's 80Ft back then another 4ft to the oil boiler..Had a 007 pump at first  then switched to a 011 pump..Water temps on the oil boiler gauge and the owb  gauge still don't match..Frustrates him..I would think the temps would match since the hot water is pumped in..He has the exact piping, insulation and everything as me.. Keep in mind its a closed loop and a direct hook up...No noticeable heat loss to the ground..Even if he had heat loss to the ground...He has a big enough pump where it still should read the same on the oil boiler.. It actually boggles my mind..
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: johnybcold on January 24, 2013, 07:27:47 PM
Thx for the replies someday I will find the phantom draw
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: willieG on January 24, 2013, 07:41:27 PM
Thx for the replies someday I will find the phantom draw
make sure you are using the same thermometer and the same way to measure each spot
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: Scott7m on January 24, 2013, 07:45:43 PM
Yup, it's really hard to get accurate readings. 

The return robs some heat on it's way back, then different surfaces, gauges, materials, angles.  It is hard
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: johnybcold on January 26, 2013, 12:45:37 PM
My return at the boiler is around 150 ,  going out boiler is 188, inside temp reads 168-170 , return on boiler reads 150 seems like I am losing slot ?
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: johnybcold on January 26, 2013, 01:42:43 PM
Measured my run it is more like 108 ft with (4) 90 degree bend and (1) 45 degree bend on each line
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: willieG on January 26, 2013, 07:52:32 PM
My return at the boiler is around 150 ,  going out boiler is 188, inside temp reads 168-170 , return on boiler reads 150 seems like I am losing slot ?
if these numbers are correct (we still don't know your true gpm but if we guessed at 5) you are losing enough btu to the earth to heat a 1200 square foot home

if you are losing 15 degrees that means you are losing 15 btu for every pound of water you are moving, if we said you were moving 5 gpm that would be about 40 pounds a min...40 x 15 is 600 btu per min x 60 min is 36,000 btu per hour (an average home uses about 30  btu per square foot per hour to heat....so 36,000 devided by 30 is a 1200 square foot home

that is a lot...i think your readings are off some or you are pumping less water?
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: Scott7m on January 26, 2013, 08:16:58 PM
My return at the boiler is around 150 ,  going out boiler is 188, inside temp reads 168-170 , return on boiler reads 150 seems like I am losing slot ?
if these numbers are correct (we still don't know your true gpm but if we guessed at 5) you are losing enough btu to the earth to heat a 1200 square foot home

if you are losing 15 degrees that means you are losing 15 btu for every pound of water you are moving, if we said you were moving 5 gpm that would be about 40 pounds a min...40 x 15 is 600 btu per min x 60 min is 36,000 btu per hour (an average home uses about 30  btu per square foot per hour to heat....so 36,000 devided by 30 is a 1200 square foot home

that is a lot...i think your readings are off some or you are pumping less water?


Hard to think he's moving less water than that, but he very well could be.  That would raise other issues as well...   
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: willieG on January 26, 2013, 08:33:15 PM
i agree scott but that seems to me to be a lot of heat loss in only 100 foot run and from the photo it looks like he is not losing heat the whole way? (at least not enough to melt the snow) but if his numbers are true then the resilts don't lie  and yes he should be moving more water than 5gpm i just used that as a guesstimate
 but that low gpm would explain the high heat loss in teh 100 foot length also?
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: Scott7m on January 26, 2013, 08:36:58 PM
i agree scott but that seems to me to be a lot of heat loss in only 100 foot run and from the photo it looks like he is not losing heat the whole way? (at least not enough to melt the snow) but if his numbers are true then the resilts don't lie  and yes he should be moving more water than 5gpm i just used that as a guesstimate
 but that low gpm would explain the high heat loss in teh 100 foot length also?


Maybe, but still don't seem right, it would have to be creeping, I can't imagine it would keep up going that slow...  It's hard telling
Title: Re: OWF reads 188 but inside boiler temp never goes over 170?
Post by: baldwin racing on January 27, 2013, 08:08:08 AM
I have a CB1400 my piping is about 70-80 feet with 3 90 degree elbows on each line, these feed into my oil boiler un pressurized ( no plate exchanger) the gauge on my indoor boiler never goes over 170, when I ran it on oil it would go over 200, do I need to burry my pipe deeper I used the CB insulted pex most of it is around 2-3 feet deep with I few spots only 8" deep, or could it be I need a bigger pump I am using a taco 007

get a digital reader and check at owb and at inside boiler the guage if macanical could be 10 degrees off and it's really at the real temp.... ;)

kelly