home made reverse fired arch

[Dale Sparrow]

14835 So here it is my home made arch. It is 3x10 with leader patriot raised flue and a algier syrup pan. Did a test boli and is set at 7gph with a flue temp of 740 degrees. Former Carlin tech was there for test boil was very impressed with burn efficiency, between 90 and 95 percent. Puts flame temp around 3,300 to 3,400 degrees. Sure made some steam! Very excited and anxious to see how much sap it will go through in an hour. I am hoping for 100+gph. Flue pan boils almost all the way to the back, last 6 inches of flue pan not boiling (it would boil if we went to 7.5 gph but flue temp was close to 800 degrees so we dialed it back a little by lowering fuel pressure. Would love to answer any questions.

[wiam]

Stack temp is kind of high. Leader recommends around 650. My homemade 3x12 runs about 630. My temp probe is about 2' above the rail the pans set on. I figure my evaporation about 130. 8' flue pan.

[Dale Sparrow]

Are you getting a boil all the way back? My temp hole is just below the rail on the tee coming out the back of the arch, that is where the burner tech wanted it. I thought flue temp was kind of high as well but seems to boil nice were it's at.

[wiam]

Boils all the way back. Most burner techs at not familiar with sugaring arches. Your stack temp is not really a stack temp. I have mine fired from the front. Hoping to reverse fire someday. I ad trouble getting front to boil until I lowered fuel pressure.

[wiam]

There is some good info here
https://www.leaderevaporator.com/pdf_files/leader-insulated-oil-arch.pdf

[Dale Sparrow]

What do you mean when you say my tack temp is not my stack temp? Do I need to go further up the stack for a true stack temp reading? If so how far up?

[WESTVIRGINIAMAPLER]

What do you mean when you say my tack temp is not my stack temp? Do I need to go further up the stack for a true stack temp reading? If so how far up?

My 3x10 CDL deluxe is running about 750. Did startup for customer today that has same evaporator just 3x12. Mine burns 8.62 gph and his is burning 9.23 and the 3x12 is running about 650 which is ideal. Hard to get 3x10 much lower as it don't have as enough flue pan to absorb enough heat to get it down lower. It is adjusted to maximum efficiency but only can absorb so much heat.

[Dale Sparrow]

The burner tech gave me a printout here are the numbers with a 45 degree 6.50 solid nozzle set at 130 psi fuel pressure , 2.2% o2, 13ppm co, 745.1 flue gas temp, 79.7% EFF, 11.5% Excess air, 13.98% co2, 15ppm undiluted co, ambient TEMP 49.6, .02 flue draft. I talked to him on the phone today and he assured me that those were excellent numbers and was comfortable with flue temp. I must admit that I did not expect flue temp to be that high, but as we lowered flue temp also began to lose boil at back of flue pan. I guess it's a wait and see how well boiling goes when the sap hits.

[wiam]

What do you mean when you say my tack temp is not my stack temp? Do I need to go further up the stack for a true stack temp reading? If so how far up?
Most are measuring stack temp 2-3 feet above the rail. Not at the rail. That explains higher reading you are getting.

[wiam]

Nozzles are rated at 100 psi. Your 6.5 is close to 7.5 at 130psi. Not saying that is bad. I am burning close to 13gph with my 701. I played with nozzle size and pressures to get it to boil sap like I wanted it to.

[Dale Sparrow]

Syrup pan boils great, nice even boil from front to back in all four channels. Was checking out stack temp gauges today, think I'll order a probe type gauge and install just below tee for barometric damper. That will put gauge about 2 feet above the rail.