Help Needed With Propane Burner Issue *PID Controlled*

Hello everyone,

I am new to posting on the forum but I have been lurking for quite sometime now. I am in the middle of building a PID controlled propane burner. I followed this diagram I got from this site.



and everything seems to be working BUT, the burner seems to pulse and sometimes back fire or even burn right at the orifice in the line. The problem is I can hear the propane cycle on and off at the same time the flame goes up and down.

Any ideas what my issue may be?

I have included a video for reference but its extremely short
http://www.youtube.com/watch?v=6qAVO7zKz2g&feature=youtu.be

THanks
Jeff

 

i could certainly be wrong, but maybe switch out the regulator and see if that solves it.

 

I Have the same set up and when mine was doing that it was a low pressure issue.

 

I was going to mention the same.
Sounds like a pressure/flow issue over a control problem.

Check your regulator and/or gas valve.

 

How have you programmed the PID controller?, looks like PID control with pulsing output, which is not going to work very well with this setup. The controller needs to be setup to be just on/off control like alarm output, no pulse type PID action. Most cases with large thermal mass and long ramp time, a PID controller is a waste of time. General rule is if it takes more than 4 minutes to reach setpoint, a simple on/off controller will work better.

 

Where did you get this from? I agree the pulse control is not useful for this use case (it would be in a RIMS tube) but do you know where the PID algorithms were developed? It was by studying how large ships were steered by the crew - the kids of adjustments they would make after years of experience to be able to gracefully maneuver the ship...talk about large mass and long ramp time.



Sent from my iPhone using Home Brew

 

most if not all of the off the shelf PID controllers only accumulate 255 seconds of error input, by which time are usually in windup mode and output is max. If PID control was enabled after reaching setpoint, then it work great as error response time would be within accumulator capacity.
After building an automated system and writing the PID control code, then refining it over the last 6 years, i might have a bit of insight as to what works and what would not. With both fast (120 K input flash boiler and fluid flow control), and slow response (mash Tun and fermenter) systems to handle, there were enough situations to learn from.