Breckwell P-23 Lateral Difference in Heat Output

[homebrewz]

I've been running a Breckwell P-23 for the last several winters and have noticed a temperature variation across the span of heat exchanger tubes. There are 12 tubes running across the top front of the stove. With the stove running on setting "B", which is where I usually have it, the left-most tube outputs hot air at about 112 f, the middle at 122 f,
and the far-right at 150 f. These measurements were made with a good quality dial thermometer with the probe stuck a few inches into each tube without touching the metal
tube itself. For each reading I held it there for a minute or two. I've noticed this before on other heat settings, but haven't measured the temperature difference until now. Incidentally, the stove is 10 years old and I'm burning Barefoot pellets this year.

I was just wondering if this is typical, or is it indicative some problem? I shut the stove down at least twice a week to brush the tubes and combustion chamber. I've only burned about 20 bags since I did the periodic maintenance.. brush and oil blowers, replace gaskets, clean passageways, sweep pipe, etc.

 

[kinsmanstoves]

I have no idea why but if it is working the way it should I would leave it alone. If you start finding a problem with something then address that issue.

Eric

 

[Lance1]

I have the P23 as well. The reason it is like this is the convection (room) blower is on the left and the combustion blower is on the right. So cold air is pumped in on the left and hot air is exhausted on the right. Has to do with the thermal transfer of the steel and air flow.

What temperature are you getting on C setting on the right tube? My measurement one inch in front of the tube is about 280°. I'm running crap pellets right now.

 

[kinsmanstoves]

I have the P23 as well. The reason it is like this is the convection (room) blower is on the left and the combustion blower is on the right. So cold air is pumped in on the left and hot air is exhausted on the right. Has to do with the thermal transfer of the steel and air flow.

What temperature are you getting on C setting on the right tube? My measurement one inch in front of the tube is about 280°. I'm running crap pellets right now.

I see the light

Thanks
Eric

 

[StoveMiser]

My big e is the same. Makes sense...

 

[homebrewz]

OK.. I suspected it might have something to do with the nature of the convection currents running in the combustion chamber.

I turned it up to level "C" about 20 minutes ago and its reading 122 on the left and 168 on the right. I'll leave it on C for a while
and take another reading later on.

 

[Lance1]

It's hard for me to get a good stable temperature reading on C setting, I only run my stove a hour or two a day. After my above post the temp was up to 295° on the right port. I had to turn the stove off because it's 78° in here. I'll try to get a B setting reading tomorrow, if interested.

You will get the hottest reading in front of the tube.

Also, all tube type stoves should work in the same manner as far as tube temp difference, depending on design.

 

[homebrewz]

Lance, are you using a magnet type stove pipe thermometer? I'm using a kitchen probe type thermometer. I just took another reading on the "C" setting and the
right side is holding at a steady 160.

 

[Lance1]

I'm using a digital Fluke dual input temperature probe, this uses J or K thermocouples. I have checked the calibration with an ice cube (home freezers usually run in the single digits and ice water will read high). I have the thermocouple mounted an inch in front of the right tube, so I only have to glance at the meter at anytime.

You may want to check the calibration of your thermometer with an ice cube and find a way to mount it (not to the stove) so your not taking short readings.

A 10° temperature rise using about a pound an hour more of pellets setting doesn't sound like enough. Do you have an OAK installed? Did you tune your flame?

Edit; I just dug up my meat thermometer and it has a range of 130-190°F, these type of thermometers are Borden Tube sensing, can be inaccurate. I can't think of any household items that can give the accuracy and range needed.

 

[homebrewz]

I don't use an OAK and I believe the flame is adjusted properly. The thermometer I was using is a dial type with a probe. Its much nicer than a meat thermometer.
It came from a pharmaceutical lab and was shop calibrated before I got it. I use it for brewing, and if it was off by more than 5 degrees f, I would notice some issues
in my brews, which I haven't.

 

[Lance1]

Sounds like you have a decent thermometer, now I see how you got your user name. You will pick up a little more heat installing an OAK, your basically pumping room heat outside right now.

I did a B setting survey and I'm getting 193° on the right port, however I'm currently burning an off brand of pellets. Something titled Tiny Timbers. I get a smaller flame with this brand.

Play with the flame tuning, it can make a difference.

 

[homebrewz]

Did you run the stove before installing an OAK, and if so, what kind of difference did you notice?
This is not a very tight house at all, btw. 1860's construction with blown-in insulation.

 

[Lance1]

I didn't do a survey before and after, but why heat the outdoors at all with your room heat. I mainly added an OAK for smoky igniter startups.

My house is pretty tight. Caulking, weather stripping, etc is cheap compared to heating/cooling costs year after year. Plus it keeps the bugs out.