Any Guess as to the Age of This Harman SF-250?

The sf 150 will be used as a stand alone system, There will not be any duct work hooked to it. So that is why I am thinking that a 75 cfm will be fine and will be warmer air. Does any one out there with a sf150 or a sf250 that has a 135 cfm have any comment? I suppose I could use the 135 cfm and put a speed control on it for when it is not going so hot, manually controlled. Thanks, Rob

I built a reducer box today for the sf150, very simple, (2) 1 1/2" els for the width approx 13 1/4" for the width, these els rest on the top of the lower firebrick holder tabs. Then some 1/4" plate, 7" stock cut to 13 1/4" length, this plate rests in/is cradled by, the els. Then I had some used firebrick around, cut to size to fit on the plate and in between the els. 3 layers of brick looks good.
The #'s , Initial volume was (17" length, 13" width, 9" height). Minus the reducer box of (7" length, 13" width. 5" height) = Remaining volume of (10" length , 13" width, 9" height). This remaining volume will hold, 20 pounds to 30 pounds, depending how I load the coal in there, flat to the lower 5" level or ramped to the 9" rear height.
This sf150 has 4 grates, So what I did was cover the 2 front grates with this box reducer. I will post some pictures.
Now back to the blower size, I think I will use a 135 cfm combined with a speed control. The reason for the speed control would be to slow the blower down if needed when I am using the reducer box, as the stove will be burning at approx 1/2 the BTU output range.
A visitor asked a simple question, "why do you have the els in there? why not just rest the plate in there." I replied,"Because the els elevate the plate above the grates so that you can still use the grates for shaking as well as give the plate "extra hold in place firmness"
The shaker handle still can move from 12 o'clock to 3 o'clock , before hitting the els/plate fixture. That is more than enough range to stay out of trouble. Any voids can be filled with ash, for a good air flow where it is needed.

Step by step procedure for reducer box, and a pic of the convection air out put on my sf150, the top lip is angled down so the air flow is directed to the bottom level top surface, I got a blower that has a motor current of 0.95 amps, I am thinking that it is 150 cfm , maybe a bit more, the air out definitely is warm enough. 200 deg stack pipe. 500+ on sides and lower top, amazingly 180 to 200 at very top, but that is because the blower is doing its job. The auto blower thermo bimetal snap control of 110f works fine on the back side, 7" away from exhaust. I am very happy with this first lighting. I believe I will stay very warm this winter. More pics to come, R

I got this today, first caller on cl, add was 23 minutes old, lucky...again. unit is in very good shape, I think I am starting to collect these now. Dual sf150's, ...???....has any one done this???

Alpine,

These will all be collector items since Harman stopped producing them. Your stoves are HXL models the predecessor of the SF models. SF models have tubes in the spiral flame chamber. HXL models do not. HXL has four grates and SF has five. Harman stopped producing the SF-250 model about two years ago and the SF-150 some years before that.

Did I see correctly that you have two coal stoves connected via flue pipe at a T connection?

Take a look at my avatar.. That is a SF-3500. The SF-250 looks identical. I purchased this stove a year ago, but I think the design has been the same for a while.

Hi, I have tried to search for info here and on the www, on the Harman HXL, but I am not finding anything, could it be that there is no info on the internet on this unit. I did email Harman about the first one, serial # HXL 209 , they replied in a week stating, that they no longer make this unit, but if I wanted parts for it, to contact a Harman dealer. I did ask them what model it was.
These HXL's both have spiral flame chambers, with air convection chamber on the entire back side, and then goes into the spiral chamber on the top, I can see the spiral welds on the side as well as reaching my hand inside the exhaust and feeling where the exhaust is coming from and going to. I also, follow the flow while it is running and up to temperature, with an Infra red laser red dot thermometer, and as I move towards the exhaust direction, the temp drops considerably. I will get the 2nd ones serial# soon. R

alpineboard wrote:Hi, I have tried to search for info here and on the www, on the Harman HXL, but I am not finding anything, could it be that there is no info on the internet on this unit. I did email Harman about the first one, serial # HXL 209 , they replied in a week stating, that they no longer make this unit, but if I wanted parts for it, to contact a Harman dealer. I did ask them what model it was.
These HXL's both have spiral flame chambers, with air convection chamber on the entire back side, and then goes into the spiral chamber on the top, I can see the spiral welds on the side as well as reaching my hand inside the exhaust and feeling where the exhaust is coming from and going to. I also, follow the flow while it is running and up to temperature, with an Infra red laser red dot thermometer, and as I move towards the exhaust direction, the temp drops considerably. I will get the 2nd ones serial# soon. R

The second HXL with the glass door= serial Number is HXL 302, So, My guess is that it was the 202'nd made.
The first HXL with the solid door= serial Number HXL 209, So my guess is that it was the 109'th made.
If the HXL model was the predecessor to the SF models, that would mean, that they were made in the late 1970's, or early 1980's. just a guess. Rob