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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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My furnace will not come on. There is a red wire coming off

Customer Question

My furnace will not come on. There is a red wire coming off the gas regulator that I don't know where it goes
Submitted: 1 year ago.
Category: HVAC
Expert:  airheatman replied 1 year ago.

Can you send me a picture of this? Also look just above that number for a model for me.That is serial number.

Expert:  airheatman replied 1 year ago.

If you have a paper clip icon on your page you can attach using that link.Or

You can upload the pictures using the tiny pic site .

Here is a link to the site.

http://tinypic.com/

Click on Browse , select the file from your folder.then click UPLOAD NOW.

They will give you a quote to enter in the box to verify you are a human.Enter the quote and click UPLOAD NOW

You will see your picture on right side of screen.

Then copy the link URL for email & IM

Paste that link here on the site.

Customer: replied 1 year ago.
My gosh I'm impressed with all the answers you have answer for people. And your high rating. It's an honor to speak to an expert like you, I know I'm in good hands now!
Customer: replied 1 year ago.
The last photo has the model number and street number written on it.... That's the only numbers I can find
Expert:  airheatman replied 1 year ago.

Thanks for those kind words,I am a licensed hvac contractor and work here trying to provide honest and accurate solutions to people's problems.I am not here to grab your payment, take a guess at what's wrong and tell you to go buy an expensive part until we are able to do some detailed troubleshooting and investigating the issue.Let me look over the pictures and pull a wiring diagram on the furnace .I will be right back with you.

Customer: replied 1 year ago.
Thank you sir, I really appreciate you.
Expert:  airheatman replied 1 year ago.

Well you sure served me a full plate here.Two screens of pictures (lol)

Now looking at furnace manual there does not seem to be a red wire to valve.but I believe someone has used this as a ground wire. Please verify that it is indeed just connected to the metal base of the vale.We will go from here.

Customer: replied 1 year ago.
I'm not sure.
Expert:  airheatman replied 1 year ago.

Excellent. Now I need you to look and tell me if you see letters by these terminals.

Customer: replied 1 year ago.
Nothing that I can see, except a funny looking symbol with three lines one big one one medium and one small one. I'll send you a picture but I don't know if I do show up
Expert:  airheatman replied 1 year ago.

Excellent they both say MV. That red wire is just a ground.Connect it to a cabinet screw somewhere.

Now our next step is to follow those two wires (blue and yellow ) connected to the MV terminals and make sure they go to the 9pin connector which ends up at control board.

Customer: replied 1 year ago.
sir they both run up to the control panel do you think that that not being grounded will keep the furnace from coming on
Expert:  airheatman replied 1 year ago.

Not really as the gas valve is grounded.It is a secondary ground.

Are there any other wires disconnected? If not, lets call for heat and tell me exactly what the furnace does and if that center green OK light flashes a code.

Customer: replied 1 year ago.
When I call for heat, The blower comes on, but the burner does not light. There is three lights in the control panel two green ones and Amber want the two green ones are's Steadley on
Customer: replied 1 year ago.
I have not what lift this furnace I thought that it was a self starting? I don't even see with the pilot light would be.
Expert:  airheatman replied 1 year ago.

OK green middle one should blink if we have a problem.Lets do this. Take a jumper wire or pair of needle nose pliers and touch the R and W terminals together on control board and see if furnace will light or we get a flashing light

http://i.imgur.com/JprQdYv.png

Expert:  airheatman replied 1 year ago.

Furnace should have an electronic ignition no pilot to light

Customer: replied 1 year ago.
OK, that did activate the little fan on the exhaust. I kept hearing it make some clicking sounds. Never lit tho. However now are metal green light is flashing. Flashes two times fast and then pauses.
Expert:  airheatman replied 1 year ago.

OK the two blinks indicates that the pressure switch is not closing.Until it does we will not get ignition. The small inducer motor pulls a vacuum on the pressure switch. Remove the rubber hose between inducer and pressure switch and blow it out.Use a straightened paper clip to clean the little fittings where hose connects to both. Re attach hose to pressure switch canister. Blow and suck a few times listening for the pressure switch to open and close. Reconnect back to inducer and turn power off then back on and try it again

Expert:  airheatman replied 1 year ago.

Storming here in Mobile AL> If I lose internet I will get back as soon as possible.Keep your fingers crossed.

Customer: replied 1 year ago.
I took that hose off on both ends and blew/sucked through it. When I suck, I can hear what her something inside there closing, so I assume that's probably a pressure switch open and closing? Heads up, I do not have the exhaust pipe running out through the roof yet. I just put in the system yet, and I wanted to make sure everything was working before I cut a hole in the roof and ran the pipe. I have big attic space, I know that's kind of dangerous to do, but I was just doing it for a few seconds to make sure it was gonna light up and work properly. I have a 3 inch pipe, that I bought to run up through the roof. 3 inch exhaust pipe is what is coming out of the unit, so I was assuming it would be a 3 inch pipe that I would run all way up through the roof, but I'm kind of confused on what size of pipe. That was going to be my next question after I got this things going. Do you think, that there some kind of sensor there that can tell that there's not enough updraft through the pipe or something maybe that's why it's not lighting?
Expert:  airheatman replied 1 year ago.

Very possible. Now you want to get a 3" x 4 " increaser and run 4 " vent.

Try this for a test.Let inducer start than remove hose from inducer, leave attached to switch.Suck on hose and keep a vacuum on switch and see if it will fire.

Expert:  airheatman replied 1 year ago.

Here is a chart showing that you need 4" vent, so get an increaser and go with 4"

Customer: replied 1 year ago.
I did keep suction on the switch with a vacuum, now there is something that will get glowing red hot for about 45 secs, but unit still won't fire off
Expert:  airheatman replied 1 year ago.

OK that is exactly what should happen except we should get power to valve after igniter glows.Do you have a volt meter?

Customer: replied 1 year ago.
If it's ok with you, can we continue this dialogue tomorrow? In the morning I'll go get the pipe up through the roof.. I think the unit is trying to start. I bought this used, and I'm wondering if it set up for propane instead natural gas. It does say it's for natural gas but there's also a sticker on there that says it needs to be factory changed if it was for LP ... Is there a simple way to tell whether the previous guy had it hooked up on LP? He lived out in the country, so I'm kind of wondering if he was on propane..
Customer: replied 1 year ago.
I do not have a voltmeter here. But I will bring one tomorrow. This is an old house that I'm working on and remodeling in hopes to resale it.
Expert:  airheatman replied 1 year ago.

Usually when converted there should be a sticker placed on valve, but you know how that goes.We can however figure it out by removing one of the burners and orifices to see what size orifices we are using. That ill take a little work but not a big deal .And yes tomorrow is fine.

Customer: replied 1 year ago.
Good morning sir! Sorry I did not get back with you the other day, The weather has been extremely cold here in Oklahoma. On this old house were working on, I resealed the wood floors, and it's taking forever for them to be dry enough for me to walk on. Part of the gable end in the attic where I have this furnace, is opened up because I have to replace some rotten wood, so the wind blows in there, and it is just too cold in that attic for a wuss like me. LOL, I am know its Sunday, if you don't want to we can wait, but I thought about re-tackling this project sometime today when you get time, if you get time? I don't think I told you, but I bought this house back in November, with the idea when spring time rolls around I'll start working on it and then try to flip it. I don't like being a landlord, and wasn't planning on renting this home. However, a guy from my church that's about 50 years old, and wasn't perfectly good health walking around just as good as me and you on a Sunday, just barely complaining about having gout in his right foot, saying he was going to go to the doctor the following the next day, Monday. The doctor told him he had a bad infection, from being a diabetic, and they amputated his leg on that Tuesday. The guy was running, walking and jogging on that Saturday, Sunday he developed a little pain in his right foot, Monday he went to the doctor, Tuesday they cut off his leg from the knee down! He's a veteran, and is currently at the VA hospital here in Oklahoma City, I was never military, but I have a huge heart for those that have served. And I always do anything I can to try to help out a veteran that fought for my freedom and freedom of my children, our military forces that are willing to fight for our freedoms is what makes this country great. Anyway, he lives in an upstairs apartment, so that's not gonna work for him when you get a release from the hospital, and he really can't afford to do much of anything else right now. So I offered this house to him, but it needed a lot of work. It had an old floor heater, that I doubt worked, and look pretty scary. Lol. I had this old heater that you and I are working on, from when I bought a used HVAC system and I only needed the outside AC unit for my home. The guy I bought it from guaranteed it to work, he was just updating his old system prior to his retirement. The AC has worked for about a year now with no problems, so I'm sure that heater works. I'm just lacking something to hookig it up, that's why called upon you. My financial situation, doesn't permit me to call an HVAC technician to come out and get this thing fired up. Lol. I really appreciate your help, and feel very confident that you can assist me. As you have already brought me a long ways in this process. So anytime you want to tackle it again, to finish it up, just let me know I could be down there this afternoon or all day tomorrow, whatever's easier for you. Also, if we get in the middle of it, and you need to stop to go make some money on the call or something, I completely understand, and we could pickup again later where we left off. BTW, I see where this site, that hooked us up, has taken five dollars out of my checking account. I remember they saying that would be a deposit. But I don't see where your process a payment for your services yet? Let May know how to pay you, and what I need to do. Thanks again for your help.
Expert:  airheatman replied 1 year ago.

I am not paid until you rate my service.I usually wait to post rating buttons until we are done.Any time you are ready to rate let me know .You can still follow up for 30 days after rating with any questions.

I should be here today so let me know when ready.

Lets start by taking the meter and checking to see if we are getting 24 volts at the gas valve between those terminals marked MV.

Customer: replied 1 year ago.
Am I need a voltmeter that will read low-voltage? Or just one that reads 110?
Expert:  airheatman replied 1 year ago.

WE will need a meter that reads from 24 to 120 volts,You can get a cheap on at Walmart for about 20 bucks.

http://www.walmart.com/ip/Digital-Multimeter-10709/14521541

Customer: replied 1 year ago.
OK I'll run down and get that thank you I'll let you know
Expert:  airheatman replied 1 year ago.

Sounds good

Customer: replied 1 year ago.
All right, I got a vote meter
Expert:  airheatman replied 1 year ago.

Ok we want to get to the point where burners should light. Inducer on, igniter light, then check between those terminals on gas vavle MV and MV to see if we get 24 volts.

Customer: replied 1 year ago.
No there's no reading there.. Also, the squirrel cage is not running now either? Only fan of running is that little fan runs before the eight at night
Expert:  airheatman replied 1 year ago.

Does igniter light?

Customer: replied 1 year ago.
Nope
Expert:  airheatman replied 1 year ago.

Lets o back to the pressure switch and suck on hose again.

Customer: replied 1 year ago.
sir it closes it
Customer: replied 1 year ago.
I'm thinking there something that I've done wrong and why in the thermostat.
Customer: replied 1 year ago.
Shouldn't there only be two wires that I need on the thermostat for the heat, can you tell me which two they are?
Customer: replied 1 year ago.
Since now there is no AC unit hooked up to the system, do I need to run a jumper wire from someplace to someplace?
Expert:  airheatman replied 1 year ago.

ll you really need is a wire to R and a wire to W from furnace board to thermostat

Customer: replied 1 year ago.
OK still not coming on.
Expert:  airheatman replied 1 year ago.

You got a wire to R and W on furnace and thermostat, calling for heat and door button in on furnace?

Customer: replied 1 year ago.
Expert:  airheatman replied 1 year ago.

OK and what happens on call for heat, does inducer start?

Customer: replied 1 year ago.
The only thing that comes on is the inducer when I asked for heat
Expert:  airheatman replied 1 year ago.

Did you run the vent out? and if you suck on hose after inducer starts will pressure switch close and igniter light?

Customer: replied 1 year ago.
Man I'm out of time tonight. What's your schedule look like tomorrow?
Expert:  airheatman replied 1 year ago.

I should be here most of the day

Customer: replied 1 year ago.
Would it be better if I paid extra and did the phone call deal?
Expert:  airheatman replied 1 year ago.

Phone call not practical for me as I am working on several different things at one time. Manage an hvac company and working with as many as eight different JA customers at one time.Not unusual to have 10 or 12 manuals on my desk at once, Phone call requires me to ignore everything else and concentrate on a one on one conversation.

Customer: replied 1 year ago.
I totally understand.
Expert:  airheatman replied 1 year ago.

Just let me know when ready to continue.