5059 Pilot Relite Contol Issue

Tim McElwain

The truth is that when the flame is established flame conductivity kicks in and the spark is shorted to ground through the flame. An example is a gas oven - when the thermostat at the manifold is turned on you will here a "tick tick" ( spark at the pilot in the oven) then it will stop and if you look the pilot to heat the capillary bulb on the oven safety is literally shorting the spark signal to ground through the flame. When the oven gets up to set point on the oven control the oven burner will shut off. The oven will then eventually repeat the spark to relight the pilot to get the oven back on to maintain oven temperature set on the control. This is due to flame conductivity caused by a nice steady blue flame with no yellow in the flame.

Tim McElwain

Time permitting I would like to walk everyone through the nightmare of the 90's and before when the gas heating industry and the government joined forces to increase the efficiency of gas heating equipment. The big deal was to shut off standing pilots. Most manufacturers got caught short as the had no system available on the residential side to do this. The only company that had a time proven system was Johnson Controls. All the rest of them including White Rodgers (5059 control), Honeywell the S86 control and Robertshaw attempting to convert their oven system over to the heating side. It was nightmare my service techs at the gas company I was working for had to work 16 hours a day 7 days a week to keep up with all the problems. The 5059 we have been talking about here was at the top of the trouble list. I will post in a separate posting later about the problems with the White Rodgers System from day one.

EdTheHeaterMan

@Tim McElwain I remember learning about the flame rectification circuitry at a Honeywell live-fire seminar many, many years ago, and how the rectifier is a result of the fact that the electrode is small and the pilot burner hood is larger in relation to the conductivity of the flame. This rectifies the AC current to a modified pulsing DC current by leaving out the other half of the (let's say lower half) of the AC current. the flame (between the 2 different size conductors) acts as a one-way check valve for the electricity. Basically the definition of a rectifier. Now I'm no electronics wiz. And I put this under the "He forgot more than you will ever know!" category. (That is the same category that refers to STEVEusaPA when it comes to oil heat, lol).

It appears that you are also in that category on many HVAC topics also.

I would like to know if you know where there are any "electronics for dummies" explanations of the FR v. FC circuitry. You can never be too old to learn something IMHO. Thanks in advance.

Merry Christmas
Ed

Tim McElwain

Ed funny you should single me out as I just enquired about you with Erin Holohan Haskell as I don't think we have touched base before on Heating Help. My background is gas. I worked for a gas utility for 28 years then went into the training business after leaving the gas company. I was the trainer for Providence gas for 18 years. As far as information I have written 35 manuals on gas systems. Eight of which we use in our one week course we run once every month here in RI. When I left the gas company I went to work for Honeywell for five years as a sub contractor doing their source program across 66 cities in the US and Canada. I have also recently written 10 manuals on Mod/Cons. My e-mail address should you want to touch base of Heating Help is timmcelwain@gastcri.com.

WMno57

Tim McElwain said:

I would like to walk everyone through the nightmare of the 90's and before when the gas heating industry and the government joined forces to increase the efficiency of gas heating equipment.

Please do. There is very little written on the history of when regulations change, and how industry meets those regulations.

Tim McElwain said:

Most manufacturers got caught short as they had no system available on the residential side to do this. The only company that had a time proven system was Johnson Controls.

Not the first time regulations (some of which come from un-elected officials, not congress) have favored some companies at the expense of others.

In 1974 the American auto industry had problems, but a large share of the domestic market. CAFE and emissions requirements destroyed that market share. Japanese and European companies had a 20 year head start due to their country's high gasoline taxes and tiny medieval streets.

In 2006 Navistar had the best medium duty diesel engine. Then came the 2007 emissions requirements. Navistar's CEO bet big on EGR. The other diesel engine manufacturers bet on SCR. EGR was a bad bet, and the CEO was forced to retire in 2012. Navistar exited diesel engine production in 2015.

The environment is important. So are jobs. Amazon, Microsoft and McDonald's cant employ everyone.

retiredguy

@EdTheHeaterMan, the scenario that you described above about flame rectification is something that was use a lot in the gas fired commercial/industrial boiler business years ago and were deemed to be the safest of all the flame safeguard systems made. Honeywell controls were what the company used exclusively but Fireye was also used in my area.

An AC voltage is applied to the "flame rod" and that voltage will pass through the flame to the ground area (pilot head). That flame movement from the rod to the grounding area would, as you wrote, would produce a half wave rectification to DC. The strength of the voltage to ground which I will call a "short circuit", my words, was read by adding a micro amp meter in series with the flame rod lead. The micro amp reading was supposed to be a minimum of 2UA to be accepted by the Honeywell primary boiler control. Early on, the meter had to wired in series with the flame rod lead on controls like the R478A and B or the RA190, but on later controls, Honeywell provided a "Jack" so the meter could be plugged into the controls amplifier . According to Honeywell the best flame signal could be obtained with a ratio of rod in the flame to the grounding area of 1 to 8, the 8 being the grounding area. Many times the pilot head had to have metal welded to it to obtain a better flame signal if the pilot head were too small and the 1 to 8 ratio could not be obtained. These controls were at one time said to be the safest how ever were also the most finicky. Thought you might like to know this.

Have a happy and prosperous New Year. David

EdTheHeaterMan

I remember sitting in a live-fire class in a hotel in a Philadelphia suburb with what looked like propane bottles of gas. It was explained that they were using Liquified Natural Gas because LP storage bottles were not allowed indoors.

I also remember the 1-8 ratio and the half-wave. They also describe the way a rectifier can be designed to use both waves to make a steady DC circuit for the electronics that might require that feature. (not used in FR).

It is interesting how the human mind works to remember trivial items that trigger the important ones that solve the problem at hand. "Do I really need to know how electronics work to clean a flame sensor or tighten a ground wire connection?" I guess that is the difference between 45 years of experience and 1 year of experience 45 times. (I just heard the expression herein last week)

Thanks for sharing.

Ed

JUGHNE

I would guess that many do not realize the importance of the ground wire in ignition proving. Might think it is important only for the sparking to occur. That was my thinking many years ago.

But learning that FR relies upon only microamps and a good path is necessary to prove flame is beneficial.
Also the 1:8 ground plane ratio can change if the pilot hood is altered.
So knowing the theory behind operation makes one think of "out of the box" ideas when troubleshooting.

Steamhead

JUGHNE said:

I would guess that many do not realize the importance of the ground wire in ignition proving. Might think it is important only for the sparking to occur. That was my thinking many years ago.

But learning that FR relies upon only microamps and a good path is necessary to prove flame is beneficial.
Also the 1:8 ground plane ratio can change if the pilot hood is altered.
So knowing the theory behind operation makes one think of "out of the box" ideas when troubleshooting.

I ran into this the other day on a call- older Dunkirk boiler with a Honeywell S86E module that had failed. The original S86E did not have a ground-wire connection, but the replacement S8610U would not sense the pilot flame until I added a ground wire between it and the gas valve. Fortunately I keep miscellaneous pieces of wire on the truck so coming up with something that would work was pretty easy.

I believe those early Honeywell modules were grounded through the mounting screws. The new ones definitely are not.

mattmia2

EdTheHeaterMan said:

I
It is interesting how the human mind works to remember trivial items that trigger the important ones that solve the problem at hand. "Do I really need to know how electronics work to clean a flame sensor or tighten a ground wire connection?" I guess that is the difference between 45 years of experience and 1 year of experience 45 times. (I just heard the expression herein last week)

Thanks for sharing.

Ed

This comes up in computer science a lot. There are a lot of people who someone taught them how to write code that compiles and those people call themselves programmers. Well that works about 90% of the time, but that other 10% of the time you have to understand what you are asking the hardware to do to know if it is something the hardware can do.

ratio

I truly believe that one can only ever be an adequate (which is, by definition, enough—most of the time.) technician, of any stripe, if one doesn't have a firm grasp of the underlying principals in play. You can see this plainly in e.g. the parts changers vs those who know the business end of a meter. Who's going to be able to explain exactly what happens?

retiredguy

When I graduated from Gateway Tech from their HVAC program I thought that I knew everything there was to know about the subjects taught. Boy, did I have a rude awakening! Years later and a couple different companies I now know that education does not start after schooling, it is just beginning. You have to learn everything you can about the equipment you are servicing. In 1972 when I switched jobs from HVAC to commercial steam and hot water systems using almost any kind of heat source, coal, hard or soft, wood, gas fuels and liquid fuels, I continued to learn until I retired in 2007. The work and the job just got too hard and heavy.

Any time I was given the job of educating a newer service tech my recommendation was always, learn everything you can about the products you see and touch, never take anything for granted, assume someone else was there before you and screwed it up, Stop, look and listen to everything around you. That machine is big, bad, and dangerous and can kill you if you make a mistake.

Then do every job as if it is for your mom or dad and remember, "the world is watching". Every job you do has your signature on it and you own it.

my 2 cents.

Tim McElwain

Ever learning but never coming to the full knowledge of the truth. At 81 years old and after over 70 years in the business (I started at nine years old emptying trash at a plumbing and heating company in SW Pennsylvania) I still seem to learn something new everyday.