I have changed all of the sensors and then I thought it was fixed. It ran and stayed lit for about 30 min and then went right back to the same problem. It will light and then the gas shuts off after a few seconds. If I let it cycle through this 3 times and then it should go to the " lock out" well it just turns the red light on once and then keeps on cycling, no lock out, no codes flashed, no solid red light, etc...

Try cleaning the flame sensor. It makes no difference if it is old or new just clean it. This will give a base line for the next test.

I just clened it with sandpaper and it lit and then died within 20 sec. I have checked and or regrounded all of the grounds as well. I am leaning towards thinking it is the HSI box. I have the white rogers / emerson electric 50E47-60. It doesn't give any trouble codes, ever...

Update, a little later I went back and switched the power on to the unit and it lit and worked for about 15 min. it was really cold in the house. After it shut down, it would not relight. But it did keep trying.

Strange that it would not run again.

Does the HSI glow during the start process?

Yes, it does. The only thing that does not happen during the ignition process "after it runs for a while and shuts off" is there is no gas flow. If you switch off the power to the unit for say... 30 min and flip it back on, it will light and run again for a bit. When the gas stopps the temp is not yet where the thermostat is set to and the his begins to glow again as if to try to relite it.

So it is an intermittent problem. Try jumping the R and W terminal on the low volt wiring strip in the furnace. This will eliminate the thermostat control and take that out of the line. This is just for testing purposes. See what it does.

Didn't help

Since you said you checked everything else I guess it is circuit board time.

Haha, yea, I think so. I have found two options the direct replacement : 50E47-60 or the one that they say has superseeded a number of older part numbers including the one I just listed. That new # is : 50E47-843. I have found either one for about $83 + s&h. the new # is supposed to be a complete conversion kit. Any advice on witch one to go with? They are White Rodgers brand controls

The conversion one is newer. Make sure to check it is the replacement for your old one.

50E47-843, Home Garden. Great deals on eBay!

Got one on the way now for $69 shipped, the -843 one. I will update once it comes in and I have a chance to install. Thanks for all of your help!

Mark all wires from old board. FOLLOW the instructions exactly on the document that comes with the new one.

Will do

Well I just installed the new unit. Now, the HSI will not glow. I am getting gas flow and everything seems to be fine. I am not sure if I should see a short across the HSI or some low impedance with the voltmeter.

The his igniter is good. I hooked up the old box and it will heat it up. The new box will not power up the ignitor. Any ideas?

Did you wire it exactly as in the instructions for the new board?

Look at this and read it over. It depends upon your system did you cut the wire or not ? The last two colums are your old board and the new one.

http://www.white-rodgers.com/wrdhom/...pg0274_277.pdf

http://www.white-rodgers.com/wrdhom/.../0037-6426.pdf

I assume you still are using a silicone carbide ignitor?

Read over and make sure purge time and all the other bells and whistles are set properly
Using your old board number as a reference.


I hate to say this but if it is wired correctly it is possible the board might be bad but I never had a bad one so??

It talks about cutting the "jumper wire" is it not good enough to just have the wire unhooked and left uncut? I didn't cut it just in case. We are only talking about 2 inches of wire that I would be cutting off, and one end is not even hooked to anything, the other end is protruding from the board of the new ignition control box. So I "DO" need to cut this and it really does matter? Haha

I also thought about trying this: the wiring right now is exactly like figure 1 on the pg0274_277.pdf file that you sent me. I thought about changing the wiring to resemble figure 3.

If you read the directions you will find out if you need to cut the wire or not. You are not cutting the wire completely out just one cut in the center of the wire is all it needs if you have to cut it to start with. It is a circuit jumper wire and if the board is used in a way that the instructions say it needs to be cut then you have to cut it.

I am not there to see your system or how it is wired but the instructions along with your OLD part number for the circuit board that was used is all you need to lookup the way to wire the new board properly. If you do not follow the directions exactly problem will happen.

You also have to set the timing of events and if you read the instructions you would see how that was to be done by using the old part number on the old board to look up exactly what to do.

Most of the time this type of repair is left to the professional HVAC person since it does require changes to the wiring but under normal circumstances anyone can do the job if they read and comprehend exactly what the instructions say to do.

All of the instructions have been followed to the T except the cutting of the jumper wire. The reason I didn't cut it is because it didn't make any sense to me. It is a wire attached to the circuit board on one end with the other end un-attached to anything. All that cutting it will do is make the same wire shorter. It will not stop a signal or anything, just make the existing wire shorter. I can send you a picture if you want me to. Just tell me where to send it to. I can also text it to you. I am hesitant to cut this wire because if the box is bad I would hate to not be able to return it because I cut a wire. If both ends were attached to something it would make more sense but since one end is just open I don't see what it will do to help, "logically". I am not arguing with you just trying to understand. Thank you!!

Post picture here. Go to advanced then to paperclip then browse your puter for pic and up load.

The green wire was supposed to be grounded, this is the "L2" wire, I made a new ground and attached it, this ground does show continuity between it and the existing grounds in the system.

The Black wire that you see me holding in the second picture is the jumper wire that we are discussing. As you see, it has a Male spade connector that is not hooked to anything. NOTE: when I opened the box this jumper wire was actually attached to the FP terminal on the box.

OK if you have a flame sensor you do not need to connect that wire. Just tape it off. The instructions say to cut it off for a reason only the manufacturer knows but it is probably to eliminate the possibility of someone at a later date and time trying to figure out why it is not connected if you know what I mean. If all else is wired as per the drawing and the correct program key is installed then you should be good to go.
Make sure the flame sensor is clean.

Ps mount that control in a professional manner and clean up the wiring so it looks good. You can leave the flame sensor wire separate since it does not take much induction electric from the other wires to screw it up.

I will deffinatley be cleaing up the install and making it look nice. I want to make sure everything works first. I have checked and double checked the wiring and everything seems to be done properly. There is a device that is mounted on the same plate that the old control box "50E47-60" is mounted to that I am not sure what it is. It is in the pictures that follow, it is black with anumber of wires going to it. The first picture shows some black and red wires going to it. Do you know what this is just by looking?

Here they are. I also thought of changing the ignitor wiring from the Figure 1 to the figure 3 as illustrated in the file that you sent me, what do you think?

Any name on it?

Any numbers on it?

Looks like relay or time delay.

What is it wired into

I can't see it right now but just about everything hooks to it. The MV1 and MV2 wires that are hooked to the 50E47 go directly to this unit, it also hooks to the switch for the vent/evacuation fan, the main gas valve and also to the Honewell unit that I am including a picture of.

Here they are

You better leave it hooked up. Without a wiring diagram I would hesitate to say because it would just be an educated guess. Stay on message and get the furnace running then we will worry about the other part.

Well, what say you about hooking the HSI as shown in figure #3 vs. figure #1 using the pg0274_277.pdf file that you sent me. (this file is the copy of the manual that I received with the new unit 50E47-843)

I really do not understand your question since I always follow the directions exactly as stated.

Are you trying to be an engineer?

Are you trying to out guess the manufacturer?

The part you purchased is universal part that is designed to replace many different types of systems available on the market. According to the manufacturer of this part it is to be installed as a carbon copy of the existing system design that was used in your furnace as manufactured to start with and NOT changed. (This is the reason they wanted the wire cut so no one would be able to play change around with the system later) I have a hard time with the fact that you read the directions and did not understand that fact. You are mentally messing around with a machine that can become real dangerous if not repaired properly.

If the system came in the furnace with a flame sensor that is what it goes back with.

If not then it is direct sense.

It is all in black and white right there in front of you on the directions.

YOU do not change the design to suit yourself since more goes into the engineering of this item than you know.

At this point it all comes down to a simple fact. You either follow the directions that came with the board/module you purchased as a replacement for the original or you do something else.

There comes a time in a help session when a poster will try and wear down a person who is trying to help them by asking off the wall questions and then not liking the answer they get they rephrase the question or ask something a bit different. We are at that point now so I suggest your follow the directions as provided by the manufacturer of your new module/ controller board OR call in a local HVAC company so they can see exactly what is going on and then play with your system following your desires. They should have the proper meters to test any system change you want to do if you can get them to do it. Liability insurance is real expensive so I doubt if they will change from the original system design. I am sorry but I do not play that game in this venue when it comes to safety.

Things can get a bit nasty when the directions are not followed.

I like the picture but let me clear up some things. I am asking about changing this because the box that I bought seems to output proper voltage across the terminals shown in fig 3 vs fig 1 that as we have seen is not working. I actually am an engineer but no HVAC guru. ;-) It seems I have frustrated you and for that I apologize. I am going to mess with it again tomorrow and then I will get a tech out to fix it if I can't fix it. If you ever have a queastion about Hondas, volvos, turbos, tuning engine management systems, or any questions about aircraft repair or piloting feel free to contact me directly, those are my areas of expeetise. Not HVAC haha thank you for your time. Mace [email protected]

I think what you are talking about is covered in the directions. Read the box (terminal wire cross ref) Both setups use flame sense and HSI so give it a try. NOTE if she runs OK then test the safety of the control by removing the flame sense wire while in operation. It should drop the gas valve out pronto.

P.E. here stamp and all. I teach HVAC sometimes at the university when I feel like it since I am actually retired from my HVAC biz.

I think you understood what I was getting to. We never know who we are helping here and that further complicates the situation.

I do understand and again thank you for the help. I have not had a chance to mess with it again as of yet. Good thing is I have a good fireplace and am able to keep the house warm with it. I will update later once I have the system fixed and running.

Ok