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Re: Why am I getting large temperature variations

PostPosted: January 17th, 2015, 2:09 pm
by Yoder_Herb
The color that you are seeing is normal. None of the Yoder Smokers cookers are designed to be air tight or leak proof. The YS1500 that I cook on did the exact same thing, in the exact same location, but has become less and less noticeable over time, and now is negligible. We have burned almost a ton of pellets through the cooker at this point, as a reference point.

We use an exterior grill cleaner to remove any of the discoloration on the outside of the cooker. We have also used dishwashing liquid and a toothbrush for stubborn debris.

What you are seeing is normal, nothing to worry about.

Re: Why am I getting large temperature variations

PostPosted: January 18th, 2015, 1:56 pm
by Wicked Chicken
When you mention "exterior grill cleaner" I'm guessing were talking about something different form the citrus cleaner for the insides?

Re: Why am I getting large temperature variations

PostPosted: January 18th, 2015, 5:26 pm
by Yoder_Herb
Yes, we have used whatever is the exterior cleaner de jour at the big box stores. Goo Gone brand is the one the boss likes the best. Good dish soap in warm water works well too.

Re: Why am I getting large temperature variations

PostPosted: January 28th, 2015, 12:26 am
by AtcTX4464
I purchased my YS 1500 last Sunday second hand. After reading some of these posts I can see where the gentleman got his information to pass along to me about temperature variations. Needless to say, I did exactly as instructed and followed the temperature that was displayed on the Hopper and disregarded the thermometers installed on the door. My first cook ended after 12 hours for 3 racks of ribs in the can. After a 12 pack of Miller Lite, I was determined that tomorrow was a new day and I was going to go at it again. I decided to adjust the Hopper temperature until I got a steady 225 on my upper thermometer. It worked out perfect, but I couldn't understand why in order to get 225 in the pit, I had to set the Hopper to 255? 30 degree swing??? I don't know if there is something wrong with my probe or what, but if I have to set the Hopper 30 degrees higher to achieve my target temperature, then so be it. My second batch of ribs were phenomenal. If anyone on here may have a clue as to what I need to do to match the temperatures better between the Hopper and pit, please let me know. I plan to run the 2 hour test this Saturday, so hopefully that will help pinpoint the problem, if in fact there is a problem at all. I ain't ruling out operator error because I've done nothing but burn sticks for the last 10 years, but the appeal of set it and forget it finally got the best of me.

Re: Why am I getting large temperature variations

PostPosted: January 28th, 2015, 1:16 am
by Yoder_Herb
First off, lets look at the function of each part of the cooker, from end to end.

On the end of the hopper is an air opening, that a fan is mounted to inside the hopper. This is referred to as the external fan. It has a fan diffuser mounted to the inside of the fan. This fan is used to "charge" the inside of the hopper, and to provide a constant source of fresh air and cooling into the hopper.

Moving deeper into the hopper, is another fan, referred to as the internal fan. This fan is attached to a air tunnel that directs a constant amount of directed forced air through the air tunnel into the firebox.

Now inside the cooker, we have the firebox. The firebox houses the igniter and is the air "accumulator" and housing that holds the burn grate.

Next is the burn grate. This is where the cooker does it business. The burn grate has an opening in it to allow the igniter to come into contact with the pellets. It also has smaller defined holes for the pressurized air from the firebox to be directed into the burning pellets to produce an efficient fire, and direct that fire upwards and out into the body of the cooker at an angle that allows the heat and smoke to traverse the length of the cooker.

In the YS1500, the next part of the picture is the Heat Management System (HMS). This was engineered and designed for Yoder wood (stick) burner cookers, and has been adapted to the YS1500. The HMS has openings (like tuning plates) that allow the heat and smoke to enter the cooking area at predetermined, even rates. The HMS also has a fire damper that allows for further tuning of the heat, and allows for a hot spot for grilling if pulled fully open.

The last part is the chimney. The chimney scavenges off the air, heat and smoke from the cooker. The chimney also has a damper, which allows for even further tuning of the heat in the cooker, and to create a hotter area on the chimney end of the cooker. If you use the damper, ALWAYS leave the damper at least 50% open, and never close it further than 50%, as this will cause issues with the functioning of the entire system and potentially cause the fire to be suffocated.

Now that the system has been explained, lets look at what can cause temperature issues:

If the fans are not working correctly, the entire system is compromised, and will cause heat fluctuations, inefficient fire, the fire may be suffocated and go out, failure to ignite, etc.

If the silicone seals around the firebox, especially the one above and to the back of the firebox, are compromised, leaking or missing, the cooker will exhibit all the same symptoms as a fan failure, and, potentially cause a burn back fire into the hopper.

If the burn grate is not kept fitting as tightly as possible in the firebox, again, all of the issues associated with the fans and the firebox silicone above. Added to this is that the silicone seal may be damaged because the burn grate is not fitting correctly.

The system was engineered, designed and built with tolerances, and requires maintenance to insure that these tolerances are maintained, and regular cleaning to remove ash. The fitment of the burn grate into the firebox is of utmost importance. If the fitment isn't maintained, the air that is supposed to be forced through the burn grate to regulate the fire and direct the heat properly through the cooker body, can escape around the burn grate, and again, cause all of the issues above.

What about the controller, thermocouple and pellet feed system? Other than regularly cleaning the thermocouple, these parts of the system are virtually maintenance free, and historically, are not a cause of heat fluctuations.

Re: Why am I getting large temperature variations

PostPosted: January 28th, 2015, 7:59 am
by Yoder_Kirby
When you turn on the controller, what letter an number does it display? b16? b20?

Re: Why am I getting large temperature variations

PostPosted: June 24th, 2015, 7:07 am
by tommyjess
Somehow I've ended up with a warped HMP, I don't know how this has happened as the highest temp I've seen is 380????
anyway I've followed the advice on rectifying the plate with a steel bar.

I started the smoker at 08:45 this morning, I set the temp to 250 to get 225, it stabilised at 225 at 09:30 and I put in a 3kg pork butt.
It held steady at 225 +/- 4 deg until 11:00 and then dropped off to 203!!!!!!!!
for the past hour it has been going up and down from 203 to 216 and as soon as it hits 216 it just as quickly drops off again, it's been 1 and 1/2 hours now since the temp dropped off.

I'm using lumberjack cherry, no foil and the damper is pushed in by 6 inches, set temp 250, H1, outside temperature 17c = 63f light wind 9 mph humidity 68% .

Re: Why am I getting large temperature variations

PostPosted: June 24th, 2015, 9:29 am
by Yoder_Herb
What is the serial number and build date from the cooker's door plate?

What is the firmware version?

Re: Why am I getting large temperature variations

PostPosted: November 24th, 2015, 9:52 am
by adambcoleman
would it not be helpful to have some sort of damper on the smoke stack?
i am also getting the large temp differences on brand new smoker, only ran the break in for about 1.5 hours, but it was set on 350 and the left and right thermos were in the 250 and 290 range or something along those lines, im gonna fire it up again but need it to work, im gonna check the things mentioned, but wondered about a damper

Re: Why am I getting large temperature variations

PostPosted: November 24th, 2015, 10:03 am
by Yoder_Herb
We used to have a damper on the chimney. Customers were experiencing hopper burn back because of not opening it, or miss adjusting it, so it was removed. It was not effective in helping with heat management, it was mainly a rain cap.

The door thermometers will never reflect what the controller displays. They are too far away from the grate, and the stems too short to get an accurate reading.

The controller is showing you physical grate temp, not suspended air temp.

Trust the controller.