Carrier Weathermaker 8000 - Model #: 58WAV090-GC Serial #: 3292A12626 -- Manu March 2, 1992 - now with intermittent ignition.
Question: The resistance on the Hot Surface Ignitor reads 95.7 -- some of the thresholds I found online says that between 30 and 200 is acceptable -- others say anything over 75 is unacceptable. I'M SO CONFUSED!
It glows real nice and has no cracks but it doesn't always ignite. Maybe one out of 10 tries, on average. Could it still be bad even though it looks really nice? Here's what usually happens:
- Thermostat calls for heat
- Blower motor starts running
- After about 12 seconds small click, Hot Surface Ignitor (HSI) Starts to glow
- After about 15-20 more seconds, no click, just "pssssssss" gas sound for about 5-8 seconds but HSI powers down with before there is any ignition - one out of every 15 no-starts, the burners will light for a half second and shut right down with the HSI
The inducer motor stays running and the HSI repeats it's process 4 or 5 times and then if there's no start, the inducer motor shuts down and system goes dormant.
There are a boatload of those igniters. The price and quality are all over the place.
They are being phased out in many older furnaces for the round type of igniter.
York/Luxaire has igniter issues.
Two things.....
Try to find a Norton 271N ...... not a sub. Those run hot.
Make sure the burner is clean where the gas comes out and hits the HSI.
Sometimes you need to slide the HSI in or out a slight bit.
I have had delayed/no ignition from some of the replacements. I've not had any of those issues with the Norton part. It seems to be getting harder to find the actual part.
That PSI gauge is either grossly inaccurate or you were measuring a high pressure supply line somewhere else.
That’s not the proper gauge for measuring gas pressure.
You’ll have to find other means of checking gas pressure at the valve and manifold.
Take the jets out and make sure the hole is clear. Visual inspection isn’t going to work or tell you anything.
This link will give you DIY instructions for a tool that would be much more accurate for gas measurement than the gauge you have. Build a manometer - YouTube
It's not as handy as the digital ones I use, but much less expensive.
There will likely be small changes to ductwork, gas piping and flu locations.
Equipment is made as a puzzle piece. You have to cut out the return air opening, there will be a knockout type panel to cut on.
It also needs to be commissioned. Gas pressure set, airflow checked. Things like that.
The gas valve will need changed. Those style aren’t allowed anymore. Your local jurisdiction may also require permits to be pulled.
Foolish me for offering the option of a DIY tool on a DIY site.
I made one long ago as a kid, and another this summer to educate my grandson. Cost was zero as I already had everything, and time spent was close to that. Oh well, it's the OP's choice and I really don't care.
Thanks again Pj - just so I'm clear, is it possible for a HSI to appear fine (glows nicely, no visible cracks, resistance within thresholds etc) but not ignite correctly?
The exchanger was match/smoke tested this fall and it was sound.
But I am now considering preemptively replacing the unit entirely - its nearly 30 years old and much less efficient than today's furnaces. I'm having the PSE&G come by next week to give me a free estimate.
Regardless, its still imperative for me to keep this furnace going to keep my family warm, so I NEED to figure this out.
I don't know if this matters or not but the longer the furnace stays off, the harder it is to start. Ring a bell?
From your experience, could I just need a new HSI?
@Pjmax > I purchased and installed the new Norton 41-409 - Model 271M HSI and there is no change - the same problem is still happening. Again, the sequence of events is:
1) Thermostat calls for heat
2) Blower/inducer motor starts running
3) After about 12 seconds small click, Hot Surface Ignitor (HSI) Starts to glow
4) After about 15-20 more seconds, no click, just "pssssssss" sound for about 5-8 seconds
5) then an audible, louder click and simultaneously, the HSI powers down before there is any ignition - one out of every 15 no-starts, the burners will light for a half second after the click and shut right down with the HSI
When it does light, it lights simultaneously with the louder click.
I have come to believe that the "pssssssss" sound is not gas being released because I have hit the tube ends with a flame/torch and there is no ignition/lighting. I don't think the gas is being released until the louder click happens. so, I suppose that somehow, the timing sequence is quirked.
My theory is that until warm, for some reason,the HSI shutdowns simultaneously with the gas valve opening. I guess this is a gas valve issue and the only true fix would be to replace the valve?
What is incoming and manifold gas pressure?
Pull the burners and gas valve assembly. Pull the nozzles and clean them. Then reassemble. Also test and adjust gas pressure at this time.
15-20 seconds is not very long for a 271N igniter. Is it actually glowing close to white hot ?
My York preheats for better than 30 seconds and it just gets hot enough.
On my burner the gas comes up thru slots in the burner tube. The location of the igniter was critical.
I could hear the pssssssss sound when it didn't light too. I thought I also smelled a bit of gas.
Newer control boards monitor igniter warmup time and ignition start and change the preheat time accordingly. My White Rodgers board has that feature. When you power down it's lost and has to cycle several times to relearn.
@roughneck77 > disassembled much of the delivery piping leading up to the valve and everything was as clean as can be. Not even a drop of water or a crumb even in the sediment trap.
I've read a little about adjusting the pressure, I suppose it couldn't hurt but I don't have the right equipment to perform that task and I'm not experienced enough. I DO have a gauge that measures the delivery pressure before it enter the furnace, and it falls well within the acceptable margins.
The flames look right (to my novice eye) when it starts so I'm not sure if that is the correct route? I suppose I could give the adjuster a "customary" turn in the right direction as see if that makes a difference. I could always turn it back.
I believe it's clockwise to increase the pressure or counterclockwise to decrease the pressure -- how far should I turn it?
DO NOT adjust the pressure without a gauge.
I did not mean pull the supply pipe apart, I meant pull the burner and clean the nozzles out.
If you measured supply pressure, what was it specifically. Gas pressure is measured in water column. Not PSI.
roughneck77 said: DO NOT adjust the pressure without a gauge.
I did not mean pull the supply pipe apart, I meant pull the burner and clean the nozzles out.
If you measured supply pressure, what was it specifically. Gas pressure is measured in water column. Not PSI.
I used this PSI gauge below, it was just under 8 lbs which is consistent with every other time I've measured it in this house over the years.
roughneck77 said:
That PSI gauge is either grossly inaccurate or you were measuring a high pressure supply line somewhere else.
That’s not the proper gauge for measuring gas pressure.
You’ll have to find other means of checking gas pressure at the valve and manifold.
Take the jets out and make sure the hole is clear. Visual inspection isn’t going to work or tell you anything.
I realize that's not the correct pressure gauge but it does show consistency. What should the PSI be? We used that same pressure gauge over-the-years in local friends houses and best I can remember, they all seem to be around 8 PSI, give-or-take? My memory is not good but that's how I remember it.
Tubes and valves are as clean as a whistle. Below is what they looked like. It seems my bi-annual cleaning/maintenance efforts actually paid off in that respect, anyway..
What should I do next?
**These pics depict the parts as they existed. I blew them all out with compressed air following but there was no blockage to speak of, none at all. I even tried to capture the INSIDE of the feeder rail / pipe to show that there is zero degradation, oxydation/rusting, gumming of debris build-up of any kind.
The gas system doesn’t run at a measurable PSI scale. It runs at inches of water column. So the manifold will run around 3.5” WC for natural gas, or 0.12644552139573745 PSI. Your gauge will not even move at a 1/4 of a PSI. It’s simply the wrong scale, that gauge isn’t usable for the purpose.
I don’t know what you were measuring and adjusting but it wasn’t gas pressure with that device. That looks more like a leak down pressure test gauge to me.
Thanks fellas.I appreciate the info. I have another question concerning replacing this furnace - because I don't know how any of this works:
Is there a chance that the new furnace I purchase will line right up as far as the flu, and ductwork?
Because if that's the case, I don't need to pay someone $2G's - in all my years of home ownership, I have really done all of my repairs myself but I figured installing a new furnace was out of my ability range. But if everything lines up, I can definitely do this.
My present furnace looks like the one pictured below and most of the new ones I'm looking at online appear to have the same setup. I have a good set of hands, quality tools and a strict desire learn and adhere to construction codes.
roughneck77 said: There will likely be small changes to ductwork, gas piping and flu locations.
Equipment is made as a puzzle piece. You have to cut out the return air opening, there will be a knockout type panel to cut on.
It also needs to be commissioned. Gas pressure set, airflow checked. Things like that.
The gas valve will need changed. Those style aren’t allowed anymore. Your local jurisdiction may also require permits to be pulled.
Thank you, friend. I'm confident cutting out the sheet metal, doing the gas piping and any flu work and the valves etc but I wouldn't even know where to start if I need to adjust the duct work. And yeah, I have no way of setting the pressure, so I guess this is why you don't hear very often of a DIY'er doing this job.
fastback said :
Foolish me for offering the option of a DIY tool on a DIY site.
I made one long ago as a kid, and another this summer to educate my grandson. Cost was zero as I already had everything, and time spent was close to that. Oh well, it's the OP's choice and I really don't care.
No sir, I absolutely appreciate your input and I should have acknowledge you sooner, my bad. Thank you, sir. I watched the video and realized that I have all of the parts on-hand and absolutely plan on building this asap.
Reviewing the posts and dates I didn't get the feeling that accuracy simplicity, or easiness was a concern. It seems that the latest turn to purchase a new one should handle all of that. While explaining what's needed for replacement you may wish to also explain how to determine if it needs a chimney liner as that is not a small price item. Or, keep it simple and let the installing company do that.
This leads to a fork in the road. Will you investigate a new furnace or try to fix your current one?
Unless your current one has a compromised heat exchanger there’s no real reason to not diagnose it.
Well, it's both for right now. Having a 30-year-old furnace, despite being well-kept and in excellent condition, brings with it a mindset that replacement-day is coming much sooner-than-later.
Cold weather is here and I need the furnace to work everyday from here-on-out or my family is cold.. While I'm trying to figure out what's wrong with this furnace, i'm also scheduling estimates for a total replacement and looking at units online.
If it's a matter of $10 bucks for a new flame sensor, this furnace lives on - but I'm not gonna spend $179 for a circuit board and another $155 for a new gas valve. That money is better spent going towards a new furnace.
Makes sense to me. If I'm on a call in your situation I would diagnosis and give options. Certainly my costs would be higher than DIY costs. But if a simple fix isn't in the cards, the service call cost would be deducted from the replacement cost. I know that kind of policy isn't unusual. Regardless of your choice, Good Luck.
yes, thanks. The manifold pressure is 3.5 - exactly where it's supposed to be. I'm still having the same issue.
Because the start-up sequencing is not really consistent, I'm going to assume that it is a circuit board issue or possibly a gas valve issue.
Question: has anyone ever attempted to rebuild one of these valves? I have the old one, just wondering if it can be done - maybe it just needs a good cleaning-out like the carburetor on your snowblower?
Gas valve is absolutely not serviceable. But what’s wrong with yours? Is it delivering proper output pressure when energized?
It doesn’t sound like a board issue either.
I have a York forced air, natural gas furnace that has recently developed a problem. The furnace has a modulating gas valve and an ECM blower motor. In normal operation, the heat output slowly ramps up as does the blower speed. After 5-10 minutes if the thermostat hasn't turned off, the blower reaches full speed. After the thermostat turns off, the blower speed ramps back down. I have my thermostat lower the night time temperature 4 degrees at 10PM. The thermostat kicks up to daytime temperature (67) at 6AM and normally takes approximately 45 minutes to raise the house temperature to daytime level.
Lately, the furnace runs for about 30 minutes and the burner shuts down while the blower remains running at approximately half speed. When I check the status LEDs on the furnace, it shows 5 red flashes, which according to the manual, means "[b]Rollout switch or auxiliary limit switch open[/b]." I have checked the rollout switch and it is not being activated. The burner flame looks normal, and the burner housing is cold.
I can get the furnace working again by either powering cycling the furnace, or merely turning the thermostat off and back on. Doing either of those things results in the furnace working normally for the rest of the day and night. Up until a couple of days ago, this was only happening every 4-5 days. Now it's doing it every morning.
I'd appreciate any response as to what the problem may be. While I ultimately will probably end up calling a service tech, I'm reluctant to do so right now since the problem is intermittent. Although, as mentioned, the problem seems to be occurring more frequently. It runs normally if all it has to do is maintain the temperature (1 degree differential). It seems to act up when it's trying to raise the temperature several degrees.
[u][b][color=#000000]FURNACE INFO:[/color][/b][/u]
[b][color=#000000]2005 Heil[/color][/b]
[b][color=#000000]Model # H9MPDO75F1281[/color][/b]
[b][color=#000000]Serial # A051790263[/color][/b]
[b][color=#000000]Honeywell Smart Valve SV9541M[/color][/b]
[b][color=#000000][u]PROBLEM[/u]:[/color][/b]
[b][color=#000000]Last winter my Heil furnace burners stopped lighting. The igniter would come on, and then the pilot light lit but the burners would not ignite. I would know that the furnace was going to eventually fail because on the previous lightings the burners would take a long time to ignite and then eventually, on following attempts, stop lighting completely. (If working properly the burners would ignite within 8 seconds or so.) The furnace would then go into a soft lockout. (6 flashes + 1 flash)[/color][/b]
[b][color=#000000]Since the initial problem, I’ve had the same crew work on the furnace and in that time they have: cleaned all pertinent parts (burner, inlet to igniter etc.), installed a new igniter, returned to adjust the new igniter, checked all grounds (listed as a possible problem), installed a new combustion blower (went bad at that time), and checked for blockage in the exhaust. It looked as if the problem was finally solved but the same issue started up again this fall.[/color][/b]
[b][color=#000000]The serviceman returned on the morning of 12/6 and he decided that the gas valve was getting stuck and therefore not allowing the burners to kick on. He ordered a new smart valve and was to contact me when it came in.[/color][/b]
[u][b][color=#000000]THE CONFUSING PART:[/color][/b][/u]
[b][color=#000000]When he left the furnace was working properly but soon failed again shortly thereafter. The furnace would attempt to ignite, go into soft lockout and then attempt again after about 5 minutes. After this went on for a few hours I went to watch the furnace when it was attempting to light and when I inadvertently put my hand over the air inlet the BURNERS IMMEDIATELY LIT. I bumped the thermostat up to heat the house well and after the furnace met the temperature it returned to soft lockout on the next attempt to light.[/color][/b]
[b][color=#000000]Later that evening, since the furnace had still not run, I again placed my hand over the air inlet when it was attempting to light and the burners lit for a 2nd time. I went to bed and apparently the furnace had not run again all night as it was 60 degrees in the house the next morning. For the third time, I placed my hand over the air inlet when attempting to light and once more the burners lit. I then blocked ⅔ of the inlet with a plastic yogurt lid and the furnace has run properly for about 14 hours at the time of this post (burner igniting quickly as it should.)[/color][/b]
[b][color=#000000]The serviceman, however, thinks it’s just a coincidence that my hand was over the inlet when the burners lit. I think it’s quite a coincidence that a furnace that had not run for 8 hours would suddenly ignite after putting my hand over the inlet. He told me he’d talk to his boss and workmates and see what they thought but I never heard back from him. BTW - it’s 32 degrees today and he never bothered to check to see if my furnace was still running.[/color][/b]
[b][color=#000000]Look, I realize that I’m just a know-nothing DIY’er but there has to be something to the restriction of air into the inlet. Can someone, anyone, please give me some feedback as to what might be the cause of the burners not igniting? Does the inlet have anything to do with the function of the Smart Valve? I would be very grateful for any input as it looks like I'm on my own.[/color][/b]
[b][color=#000000]Thanks in advance![/color][/b]
11-22-21, 07:33 PM
