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Have you checked both intake and exhaust vents to make sure no birds or dit dobbers have built nest and they are free and clear?
I checked the exhaust vent on the roof and found a small bees nest in it. I removed that but it did nothing to resolve the problem. By intake vent are you referring to the cold air return ducts that come in to the top of the furnace?
I also took off the top panel and checked the fuse that plugs into the circuit board and that is good. One more note for you that may help is that the light on the thermostat is always red and not green. I don't know if that means anything since the furnace is not operational, but I figured I may as well throw in as many facts as I know.
By 'control board' do you mean the circuit board that sits in the top portion of the furnace box that is visible when I take off that top panel - where the large blower fan is housed? The furnace does come on now, it just wont ignite and then shuts down again.
Ok. I was not aware that it was actually coming on. I see you mentioned it does periodically. Lets skip that step if the inducer motor is actually coming on with the thermostat. Lets start by turning power OFF to furnace and thermostat OFF. Then
power the furnace back up and call for heat on thermostat.Let me know exactly how far the furnace goes in this sequence( Inducer comes on, pressure switch closes, igniter light,burners light, then blower starts). At that point we should get a trouble code on the circuit board indicated by how many times the led flashes before pausing.Let me know the number of flashes.We will go from there to determine what is failing.
I'm not sure how to tell if the inducer switch comes on or when the pressure switches close. But the lower fan starts up, runs for a while, and then everything just shuts back down. I am getting no ignition, no burners light, and the upper blower does not start up.
I get 8 red LED flashes of the furnace control board before a pause.
8 flashes indicates that there is a problem with the ignitor itself. It says one of the follow is the issue.Mis connected ignitor( Unplug the ignitor and plug back in making sure we have a good connection),bad ignitor( If you have the hot surface ignitor,look closely and make sure there is no burned place on the ignitor like in this picture)or the last thing it mentions is a poor equipment ground(Make sure unit ground is good).
The only thing that bothers me is that the inducer motor should be starting as soon as the thermostat calls for heat. Check these things good . Next, try leaving power off to furnace for about 5 minutes to make sure circuit board resets and back on to verify the code.If you still get 8 flashes, there must be an issue with one of above items. Let me know
Sorry, that was my 1st attempt at sending a pic and apparently I didn't size it correctly. There was a lot of rust around the top of it where it mounted to the sheet metal so I sanded the rust off so there was a good metal to metal contact in case that had anything to do with grounding. All the other ground points seem to look good to me and this igniter looks the same as the last time I removed and looked at it back when it was working.
Personally at this point, I would probably call in a tech to verify the problem.It sounds as though you may have a defective computer board (IFC). If you have verified that the igniter circuit and igniter are fine, then the 8 flash code is a false code.(IFC board giving false code). Also the first thing that should take place is the inducer motor is not coming on and that is the first thing the board should do is send signal to the induced draft vent motor to come on.
The reason I recommend having it verified is the board is probably around 150 bucks.You can Google the part number on the board to locate one.I just hate making recommendation for replacing a part that expensive without being there to actually troubleshoot on site.
Tim, I think you are misunderstanding which motor I am saying comes on. If you are looking at the same Amana schematic as I have on the back of the manual then it is reversed from my furnace setup. When I say the lower fan starts up I believe this is probably what you are calling the inducer motor. If this is the motor in the same compartment with the air switches mounted all around it and the 4 gas jets and gas manifold just below it, then this would be the lower compartment on my furnace instead of the upper as shown on the Amana diagram.
And yes that motor does come on first thing. It runs long enough for the system to realize that there is no ignition and then shuts down. This is the same thing it was doing the last time I had a problem and found that there was water in the lines going to the air switches. I cleared the air lines, resolved the problem that was causing water to get into the lines, and it fired right up and ran great for about 4 or 5 months. While we have been working on this I have double and triple checked those lines for water and there is none.
How did that igniter in the pic look to you? Even when the furnace was working I have never seen this thing start to glow in any way - is it supposed to? Is that how this igniter works, or does it jump a spark to something I am not seeing back in there? It looked OK to me but I'm not the expert - and if it looks questionable then it seems that it would be a pretty cheap part to replace in order to rule it out.
And how about that thermostat, have we ruled it out. I have always wondered why the light on it was red even when the furnace was working.
The ignitor looks pretty rough .It should glow a bright orange and heat up before the gas valve will open.AS for the thermostat.I would need the model on the thermostat to know which stat you have so I can pull a manual on it.
The ignitor is only about 30 bucks.You can get the part number and Google it if you want to lets start there.The 8 flashes definitely states it is an issue with the ignitor.
And about the motor, I thought you were saying the main blower was coming on.If inducer fan vent motor is coming on, I highly suspect the ignitor needs to be replaced from looking at it and if it does not glow bright orange
The thermostat is a TOTALINE Programmable Thermostat (P/N 0441). I will see if I can pick up a new igniter somewhere locally tomorrow and get back to you once I have installed the new one.
That's the one - model # XXXXX
Tim, sorry I didn't get back to you sooner. I had some work I had to get right on. I checked on the igniter and its going to run $80 - $90, so I am trying to positively determine as to whether or not that actually is the problem. One thing I did do was to unplug the igniter and plug the two leads from a voltmeter into the plug end that the igniter was plugged in to - I'm assuming that they come off of the circuit board. I then cycled on the furnace a couple of times to see if any juice was even being sent down to the igniter from the circuit board. I don't know if this would be enough to even light up the voltmeter or if I should have used an ohm meter or something instead. In any case I got nothing. So now I'm wondering if it might actually be the circuit board, or possibly even both. Would it work for me to plug a continuity tester on to the leads coming off of the igniter to see if it is good or bad? It seems that there should be a fairly simple way to test these two items.
Hello, I amCustomerand will try to assist you. I see Tim has opted out so I will try to assist. It sounds like you have a down flow furnace. The combustion blower (for burners) is at the bottom and the main blower for your home is at the top, correct? Now to find out if you need a new board or ignitor what you need to do is....... pull wires off pressure switch. keep apart. make a call for heat when lower combustion blower comes up to speed connect the two wires you took off pressure switch. hold together. after about 30 seconds the ignitor should start to glow and 15 seconds from there the gas valve should open and flame. If you were getting water into your pressure switches a year ago it could have rotted the diafram so the switch is not closing. Now if you bypass the pressure switch and the ignitor still does not glow and you measure 0.0 volts at line going to ignitor then the board is bad, not energizing the the ignitor. Do a ohm test on ignitor it should be between 70 and 100 ohms.Customer/p>
Servtech50, Yes you are correct, it is a down flow furnace. I went out and bought a digital multimeter so I could do the tests you wanted, but when it comes to electrical I am a relative dunce so I am sending pic's of the teAttachments are only available to registered users.Register Herests I did. When I powered up the furnace the inducer (blower?) motor starts up and then almost immediately after that I get a reading of 7.3 volts on my multimeter as shown in the picture (assuming that I have the multimeter set correctly). Is that enough to get this igniter glowing? When I hook up to test the igniter I can't get a reading any higher than 8.96, unless I am testing it wrong this is nowhere near the 70 - 100 you mentioned I should get. Also, you mentioned disconnecting the wires to the air pressure switch and connecting them together to see if it may be the air pressure switch diaphragm that is rotted out - the problem is that I have 3 of those switches. Which one do I do that to, or do I have to do it to all 3 of them? Sorry for the long pauses between correspondence but I have been, and still am, sick and on top of that have been having to still work do to being under the gun on a job.
Attachments are only available to registered users.
I jammed the probes into the molex connector and both probes are in there securely with a good contact with the metal ends that are pinched onto the ends of the wires entering the connector. It does not run for 30 seconds before I get a reading, I start getting a reading as soon as it kicks on, the motor runs for about 12 seconds and then it turns off and it reads 7.3 volts throughout that period.
I am attaching the pic of the test on the igniter. I get no reading except 1. on the 200 and 2K settings. I get a reading of 8.96 when I click it over to the 20K setting.Attachments are only available to registered users.Register Here
I think there are some typos and I'm having a little trouble understanding the response. OK, I put a jump wire from terminal R to terminal W - that part I get. Now in the next part I'm thinking you are saying that I power it up and place one of my probes on the W terminal and the other probe on the C terminal, and when I do this I should get a reading of 24 volts? Or are you saying that I will get a reading of 24 volts and then possibly loose it when the inducer motor kicks on or something? Does it matter which color probe goes on which terminal, W or C,or does it not matter since it is alternating current?
Also, to answer your question, when I touch the probes together at the 200 ohm setting it goes slightly up in scale and then zero's out. So I'm assuming the meter is working correctly?
I have to go out for a bit but I'm going to also attach the picAttachments are only available to registered users.Register Here of the 3 air switches just in case this all ends up leading us there. The front 2 are piggy backed.
OK, I turned on the power, held in the cover switch, held the black probe on C and the red probe on W1 (there is a W1 and a W2 terminal, but they are jumped together with a small copper wire so I don't think it made any difference), and then I called for power at the thermostat. When the inducer motor kicked on the meter went from 0 to 24.5V. The inducer motor runs for about 12 seconds and then shuts down, but I still have 24.5V on the meter - I'm assuming that this voltage will stay active at those terminals until the red light on the thermostat goes off. What I'm not understanding is why I have 24.5V at the terminals and only 7.3V at the molex connection down by the igniter. How many volts does it take to make the igniter work?
I have not jumped R & W terminals yet to see if the furnace still runs. I will do that next if you think it is still necessary.
Model # GCVA090BX50 Amana High Efficiency Gas Furnace (2 stage variable speed). Yes, there is a flashing code - I get 8 red flashes on the red led light off center on the board (this is the one you would see through the clear plastic peep hole in the cover panel).
The green led at the corner of the board also flashes, but its a bit different. It starts off glowing dim and then brightens up and flashes either 8 or 9 times, then goes out, starts up dim again and cycles through the same thing again.
Sorry, I am having some real internet problems and am having to currently hotspot to my phone just to be able to get online. Long story short. I did the continuity test on the air switch and it is opening and closing. Also I get continuity immediately when the inducer/ventor motor starts up.