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J Diddy
02-01-2011, 01:35 PM
Is it possible that snow build up in the exhaust pipe going through the roof could prevent the inducer motor from activating thereby preventing my heater from coming on?

Bugeater
02-01-2011, 02:09 PM
That pipe should have a cap on it.

JD10367
02-01-2011, 02:10 PM
Check the flux capacitor and make sure the dilithium crystals haven't polarized.

Seriously... Seems like a convoluted solution for what's probably an easier problem (blown fuse, bad thermostat, etc.,.). Break out the multitester and start tracing backwards.

J Diddy
02-01-2011, 02:10 PM
That pipe should have a cap on it.
It does but unfortunately it's also got snow encompassing it. there's literally 1 foot of snow or more on top of the roof.

Bugeater
02-01-2011, 02:18 PM
It does but unfortunately it's also got snow encompassing it. there's literally 1 foot of snow or more on top of the roof.
Well, I can tell you this much, if it's not getting adequate ventilation, you're better off with the furnace not running because carbon monoxide can back up into your house. I suppose there may be some type of sensor that shuts the furnace down in the event of a CO backup. I could probably give you a better answer in May after I've completed my gas heat course.

Phobia
02-01-2011, 02:20 PM
BE is correct. You'll need to clear the exhaust/intake before the sensor will allow the furnace to run. Although, I'd think it would extend beyond a foot over the roof.

NCarlsCorner2
02-01-2011, 02:24 PM
If the furnace had been running you wouldn't have any build up of snow due to the heat from the exhaust, so I would say your problem is something else, turn the thermostat from auto to fan on to see if the blower motor comes on, if so your transformer is good and you have power to the furnace.

NCarlsCorner2
02-01-2011, 02:26 PM
Well, I can tell you this much, if it's not getting adequate ventilation, you're better off with the furnace not running because carbon monoxide can back up into your house. I suppose there may be some type of sensor that shuts the furnace down in the event of a CO backup. I could probably give you a better answer in May after I've completed my gas heat course.

The pressure switch won't close if the flue is blocked.

jspchief
02-01-2011, 02:29 PM
buy a snow rake

Saul Good
02-01-2011, 02:50 PM
Do you have a laptop? If so, take it up on the roof with you, and I'll walk you through what you need to do. If not, I'm happy to give you step by step instructions based on what you see up there. You'll need to come back down from the roof and report back to me what you see after each step, though.

J Diddy
02-01-2011, 03:02 PM
Do you have a laptop? If so, take it up on the roof with you, and I'll walk you through what you need to do. If not, I'm happy to give you step by step instructions based on what you see up there. You'll need to come back down from the roof and report back to me what you see after each step, though.

Lol, yes I have a laptop. No I'm not going up there. Landlords here hopefully he'll fix it. Otherwise I've got to get creative, for it is not just me, but me two children as well.

NCarlsCorner2
02-01-2011, 03:05 PM
Lol, yes I have a laptop. No I'm not going up there. Landlords here hopefully he'll fix it. Otherwise I've got to get creative, for it is not just me, but me two children as well.

Does the furnace come on at all?

J Diddy
02-01-2011, 03:10 PM
Does the furnace come on at all?no pilots lit, he's testing out the voltage right now, but I'm not really sure he knows what he's doing

Saul Good
02-01-2011, 03:11 PM
no pilots lit, he's testing out the voltage right now, but I'm not really sure he knows what he's doing

That's why you need to get on the roof. We can have this fixed up in 3-4 hours, tops.

NCarlsCorner2
02-01-2011, 03:13 PM
no pilots lit, he's testing out the voltage right now, but I'm not really sure he knows what he's doing


I work in HVAC, so let me know and i'll try and help you, is it a standing pilot or HSI, if you have a inducer motor that is the first thing that needs to come on.

J Diddy
02-01-2011, 03:13 PM
I work in HVAC, so let me know and i'll try and help you, is it a standing pilot or HSI, if you have a inducer motor that is the first thing that needs to come on.


It is not, it is a standing pilot

NCarlsCorner2
02-01-2011, 03:17 PM
It is not, it is a standing pilot

Then you could just have a bad thermocouple, turn the knob on the gas valve to pilot and try to light it, if the pilot head is dirty you might not be getting a good flame on the thermocouple therefore it won't stay lit.

J Diddy
02-01-2011, 03:28 PM
Then you could just have a bad thermocouple, turn the knob on the gas valve to pilot and try to light it, if the pilot head is dirty you might not be getting a good flame on the thermocouple therefore it won't stay lit.

the pilot is lit, I put it out then relit it

NCarlsCorner2
02-01-2011, 03:31 PM
the pilot is lit, I put it out then relit it

Do you have a good flame hitting the end of the thermocouple, make sure the knob is now turn to the on position at the gas valve and calling for heat at the thermostat, also make sure you have changed your filter so it doesn't go out on high limit.

NCarlsCorner2
02-01-2011, 03:37 PM
Did the furnace come on?

J Diddy
02-01-2011, 04:02 PM
Did the furnace come on?


Lol after him piddle farting with the electrics in it, I finally convinced him to try my theory. We went on the roof, cleared around the pipe which was encased in approximately 3 foot snow drift and whammo. We got heat, I'm cranking that up to 85 which should keep it running all night and hopefully keep it cleared.

NCarlsCorner2
02-01-2011, 04:07 PM
Lol after him piddle farting with the electrics in it, I finally convinced him to try my theory. We went on the roof, cleared around the pipe which was encased in approximately 3 foot snow drift and whammo. We got heat, I'm cranking that up to 85 which should keep it running all night and hopefully keep it cleared.

That's not the problem though, if the furnace had been working it should have never let the snow pile up due to the heat from the flue gas, if the pilot goes out again change the thermocouple, glad it's working.

J Diddy
02-01-2011, 04:11 PM
That's not the problem though, if the furnace had been working it should have never let the snow pile up due to the heat from the flue gas, if the pilot goes out again change the thermocouple, glad it's working.

Definitely, will pass that on. Kinda hard to do anything right now though, lol. Like I said 3 feet of snow on a flat trailer roof.

Thanks for the help sir.

chefsos
02-01-2011, 04:33 PM
Definitely, will pass that on. Kinda hard to do anything right now though, lol. Like I said 3 feet of snow on a flat trailer roof.

Thanks for the help sir.:eek: Mr. Landlord needs to get that shit off of there pronto.

Saul Good
02-01-2011, 05:18 PM
:eek: Mr. Landlord needs to get that shit off of there pronto.

Yep. You're gonna have 3 feet in your living room, otherwise.

googlegoogle
02-01-2011, 06:35 PM
Damn thermocouples. Worse than a flux capacitor.

JD10367
02-01-2011, 07:29 PM
I work in HVAC, so let me know and i'll try and help you, is it a standing pilot or HSI, if you have a inducer motor that is the first thing that needs to come on.

Tech talk is so hot. I think I just felt my thermocouple stir. :D

J Diddy
02-01-2011, 07:40 PM
Damn thermocouples. Worse than a flux capacitor.

BS, I've never had to get my trailer home up to 85 for it to work.

jd1020
02-01-2011, 08:36 PM
That's not the problem though, if the furnace had been working it should have never let the snow pile up due to the heat from the flue gas, if the pilot goes out again change the thermocouple, glad it's working.

You should work on your HVAC, tbh. This isn't an uncommon problem when it comes to high effiency furnaces. If the exhaust is blocked the inducer fan is not going to be creating enough pressure to close the switch and continue with the order of operations. A heavy snow like today will cover the exhaust. This is why there are regulations for the height of the exhaust exiting a rooftop or sidewall.

Hog Farmer
02-01-2011, 08:52 PM
Well, I can tell you this much, if it's not getting adequate ventilation, you're better off with the furnace not running because carbon monoxide can back up into your house. I suppose there may be some type of sensor that shuts the furnace down in the event of a CO backup. I could probably give you a better answer in May after I've completed my gas heat course.

For some people carbon monoxide can be a good thing.

Over-Head
02-01-2011, 09:37 PM
Like I said 3 feet of snow on a flat trailer roof.. I didn't know it was snowing in Oakland???:D

J Diddy
02-01-2011, 09:43 PM
For some people carbon monoxide can be a good thing.

It has done wonders for you.

J Diddy
02-01-2011, 09:47 PM
I didn't know it was snowing in Oakland???:D
Now come on, I didn't say someone stole my trailer.

Over-Head
02-01-2011, 09:55 PM
Now come on, I didn't say someone stole my trailer. Sorry sorry, sorry...didn;t mean to offend a Miami fan ;)

J Diddy
02-01-2011, 10:04 PM
Sorry sorry, sorry...didn;t mean to offend a Miami fan ;)



Miami?

Over-Head
02-01-2011, 10:15 PM
Miami? Aint that where all the other trailers are parked in the USA?....Other than the ones in Tornado Alley

J Diddy
02-01-2011, 10:19 PM
Aint that where all the other trailers are parked in the USA?....Other than the ones in Tornado Alley


never heard that, nor have I been to miami

However I saw an ungodly amount of trailers in GA

NCarlsCorner2
02-02-2011, 08:34 AM
You should work on your HVAC, tbh. This isn't an uncommon problem when it comes to high effiency furnaces. If the exhaust is blocked the inducer fan is not going to be creating enough pressure to close the switch and continue with the order of operations. A heavy snow like today will cover the exhaust. This is why there are regulations for the height of the exhaust exiting a rooftop or sidewall.

You should do the same, a blocked flue will not keep the inducer motor from coming on, go back and read the original post he said would a block flue keep the inducer motor from coming on, the inducer motor will come on blocked or not it just won't close the pressure switch.


Is it possible that snow build up in the exhaust pipe going through the roof could prevent the inducer motor from activating thereby preventing my heater from coming on?
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jd1020
02-02-2011, 10:57 AM
You should do the same, a blocked flue will not keep the inducer motor from coming on, go back and read the original post he said would a block flue keep the inducer motor from coming on, the inducer motor will come on blocked or not it just won't close the pressure switch.


Is it possible that snow build up in the exhaust pipe going through the roof could prevent the inducer motor from activating thereby preventing my heater from coming on?
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I'm not commenting on what he said. The inducer will not continue to run. It will shut off after a bit then retry.

I'm commenting on your statement about how the exhaust should never get blocked, which is completely stupid.

NCarlsCorner2
02-02-2011, 01:23 PM
I'm not commenting on what he said. The inducer will not continue to run. It will shut off after a bit then retry.

I'm commenting on your statement about how the exhaust should never get blocked, which is completely stupid.

If the furnace is running it shouldn't get blocked by snow, were not talking about PVC here to my knowledge and since he has a standing pilot chances are that he doesn't even have a inducer motor, I just tried to help the guy fix his furnace which is hard to do if you don't have very much info, but to question my HVAC knowledge is stupid on your part is what i'm saying.

jd1020
02-02-2011, 02:47 PM
If the furnace is running it shouldn't get blocked by snow, were not talking about PVC here to my knowledge and since he has a standing pilot chances are that he doesn't even have a inducer motor, I just tried to help the guy fix his furnace which is hard to do if you don't have very much info, but to question my HVAC knowledge is stupid on your part is what i'm saying.

Sure. I'll just take my HVAC field tech self elsewhere. I've delt with this certain issue plenty of times. It's one of the first things I look for on a no call for heat when the operation stops at the inducer.

Now you are saying because he has a standing pilot that he likely doesnt have an inducer fan??? Have you been in the field? There are >80% furnaces that have standing pilots. I would guess that he has an intermittent pilot before questioning if he has an inducer.

NCarlsCorner2
02-02-2011, 03:50 PM
Sure. I'll just take my HVAC field tech self elsewhere. I've delt with this certain issue plenty of times. It's one of the first things I look for on a no call for heat when the operation stops at the inducer.

Now you are saying because he has a standing pilot that he likely doesnt have an inducer fan??? Have you been in the field? There are >80% furnaces that have standing pilots. I would guess that he has an intermittent pilot before questioning if he has an inducer.

I know everything your talking about, what i'm saying is with the lack of info that I had how can you judge my knowledge of HVAC, everything your saying is true but so is what i'm saying, I know all about Carrier 3 wire pilots with an inducer motor, I know all about PVC flue pipes icing up outside, I know all about birds getting down a chimney all the way to the inducer motor, yes I have worked in the field and have seen it all, but after I was trying to help him one of the things that he failed to say up front was the fact that it was a trailor, also how many houses have you ever had to get up on the roof to shovel snow away from the b-vent flue pipe.

jd1020
02-02-2011, 03:53 PM
I know everything your talking about, what i'm saying is with the lack of info that I had how can you judge my knowledge of HVAC, everything your saying is true but so is what i'm saying, I know all about Carrier 3 wire pilots with an inducer motor, I know all about PVC flue pipes icing up outside, I know all about birds getting down a chimney all the way to the inducer motor, yes I have worked in the field and have seen it all, but after I was trying to help him one of the things that he failed to say up front was the fact that it was a trailor, also how many houses have you ever had to get up on the roof to shovel snow away from the b-vent flue pipe.

Not many. It's generally ice build up on wall vented 90%'s. But then again, these 12''+ snow storms arent that common in the lower midwest.

NCarlsCorner2
02-02-2011, 03:57 PM
Not many. It's generally ice build up on wall vented 90%'s. But then again, these 12''+ snow storms arent that common in the lower midwest.

I have never had to get up on a roof to shovel snow away from a flue with a running furnace, after the 12 inches of snow that we just got there isn't 12 inches of snow on my roof, now a flat trailor roof might be a different story, but I didn't have that info at first.

jd1020
02-02-2011, 04:01 PM
I've seen pretty heavy build up on <2-12 grade roofs.

NCarlsCorner2
02-02-2011, 04:04 PM
I've seen pretty heavy build up on <2-12 grade roofs.

But the heat from the flue gas will melt any snow that gets close to the cap, the only way it could possibly get over the flue is if the furnace wasn't running for a long period of time IMO.

J Diddy
02-02-2011, 06:51 PM
But the heat from the flue gas will melt any snow that gets close to the cap, the only way it could possibly get over the flue is if the furnace wasn't running for a long period of time IMO.

I mean it did dump 13 inches in like 2 hours.

J Diddy
02-02-2011, 06:52 PM
But the heat from the flue gas will melt any snow that gets close to the cap, the only way it could possibly get over the flue is if the furnace wasn't running for a long period of time IMO.


and 4 other trailers had the same problem

Bugeater
02-02-2011, 06:53 PM
But the heat from the flue gas will melt any snow that gets close to the cap, the only way it could possibly get over the flue is if the furnace wasn't running for a long period of time IMO.
We had that exact thing happen at our office today, and we didn't get anywhere near as much snow here. It was a flat commercial roof though, not sure if that makes a difference.

NCarlsCorner2
02-02-2011, 07:26 PM
I mean it did dump 13 inches in like 2 hours.

That might be a world record, it was only coming down an inch an hour here.

NCarlsCorner2
02-02-2011, 07:29 PM
We had that exact thing happen at our office today, and we didn't get anywhere near as much snow here. It was a flat commercial roof though, not sure if that makes a difference.

You better have them extend the flue pipe up higher.

J Diddy
02-02-2011, 08:20 PM
That might be a world record, it was only coming down an inch an hour here.

an exaggeration for sure.

Point being the snowfall was heavy

Bugeater
02-02-2011, 08:23 PM
You better have them extend the flue pipe up higher.
Yeah probably, although I haven't seen it nor do I know the layout of the roof or any of the other circumstances surrounding it, but it does seem to be a flukey thing to happen.

plbrdude
02-02-2011, 09:15 PM
If the furnace is running it shouldn't get blocked by snow, were not talking about PVC here to my knowledge and since he has a standing pilot chances are that he doesn't even have a inducer motor, I just tried to help the guy fix his furnace which is hard to do if you don't have very much info, but to question my HVAC knowledge is stupid on your part is what i'm saying.

kind of followed this post but didn't throw in my 2 cents worth. but you would be right, if it is a standing pilot furnace it shouldn't have an idm. as a matter of fact even if it was hsi it probably wouldn't have an idm;if it is a mobile home furnace.
from what i've seen coleman and nordyne pretty muchly have a lock on the mobile home market and their furnaces have a combustion air intake motor which brings the air into the combustion chamber; it doesn't really send it out.
that being said, if the flue did get snow covered more than likely the upper high limit should have opened shutting down the furnace. some of these automatically reset, most are manual. could be a chance that mr. landlord reset it before cleaning the snow off.
side note, most, if not all mobile home roof jacks are pretty well fixed and it would not be a good idea to try and raise the flue. they are a two pipe system which brings combustion air in between the outermost pipe and the flue. 4" inside of an 8"

J Diddy
02-02-2011, 09:54 PM
kind of followed this post but didn't throw in my 2 cents worth. but you would be right, if it is a standing pilot furnace it shouldn't have an idm. as a matter of fact even if it was hsi it probably wouldn't have an idm;if it is a mobile home furnace.
from what i've seen coleman and nordyne pretty muchly have a lock on the mobile home market and their furnaces have a combustion air intake motor which brings the air into the combustion chamber; it doesn't really send it out.
that being said, if the flue did get snow covered more than likely the upper high limit should have opened shutting down the furnace. some of these automatically reset, most are manual. could be a chance that mr. landlord reset it before cleaning the snow off.
side note, most, if not all mobile home roof jacks are pretty well fixed and it would not be a good idea to try and raise the flue. they are a two pipe system which brings combustion air in between the outermost pipe and the flue. 4" inside of an 8"

Which is correct. He cleaned the flue and hit the reset and whammo.

The 2 pipe system is what screwed us. 1 sorta covered, 2 entirely covered

JD10367
02-03-2011, 02:11 AM
This is interesting. I've seen many an e-penis battle on the Internet, but never centering around a knowledge of HVAC. :D

NCarlsCorner2
02-03-2011, 01:41 PM
This is interesting. I've seen many an e-penis battle on the Internet, but never centering around a knowledge of HVAC. :D

That's why you shouldn't call someone stupid when you don't have the full story.

NCarlsCorner2
02-03-2011, 01:44 PM
kind of followed this post but didn't throw in my 2 cents worth. but you would be right, if it is a standing pilot furnace it shouldn't have an idm. as a matter of fact even if it was hsi it probably wouldn't have an idm;if it is a mobile home furnace.
from what i've seen coleman and nordyne pretty muchly have a lock on the mobile home market and their furnaces have a combustion air intake motor which brings the air into the combustion chamber; it doesn't really send it out.
that being said, if the flue did get snow covered more than likely the upper high limit should have opened shutting down the furnace. some of these automatically reset, most are manual. could be a chance that mr. landlord reset it before cleaning the snow off.
side note, most, if not all mobile home roof jacks are pretty well fixed and it would not be a good idea to try and raise the flue. they are a two pipe system which brings combustion air in between the outermost pipe and the flue. 4" inside of an 8"

Or just turning the furnace off and back on could reset it, next time I see a person wanting help fixing their furnace or A/C I will just sit back and watch like you.

kepp
06-10-2011, 07:44 AM
HVAC question here - the motor on our air cond unit (the unit that sits outside with the fan) just went out yesterday. The motor was replaced three years ago almost to the day and it cost $400 ($320 for the motor). My question is, if I can get my hands on a motor, is it easy to replace myself? Is it really something that requires a trained technician?

Also, does anyone know how I can get a motor?

Extra Point
06-10-2011, 07:57 AM
HVAC question here - the motor on our air cond unit (the unit that sits outside with the fan) just went out yesterday. The motor was replaced three years ago almost to the day and it cost $400 ($320 for the motor). My question is, if I can get my hands on a motor, is it easy to replace myself? Is it really something that requires a trained technician?

Also, does anyone know how I can get a motor?

Comfort Products, Johnstone Supply, United Refrigeration. Look under "Air Conditioning Parts and Supplies" in the YP. Bought a motor for the furnace from United, years ago. GL. If it's the compressor motor, those can be sealed w/ the compressor, but it sounds like yours isn't. Write down all the info before calling. Good luck.

Alton deFlat
06-10-2011, 07:58 AM
HVAC question here - the motor on our air cond unit (the unit that sits outside with the fan) just went out yesterday. The motor was replaced three years ago almost to the day and it cost $400 ($320 for the motor). My question is, if I can get my hands on a motor, is it easy to replace myself? Is it really something that requires a trained technician?

Also, does anyone know how I can get a motor?

If you are careful, you should be able to replace the motor. MAKE SURE YOU SHUT OFF THE POWER, but it's fairly simple. Most of those motor are 1/4, 1/3, or 1/2 horsepower, and they will also have a capacitor, that I would change at the same time. Capacitors will have a MFD rating stamped on them (i.e. 5 mfd, 370 volts). You will need this information. If you have a Grainger or Johnstone Supply close to you, that would be a good place to start. The fan blade, may be a lttle difficult to remove, especially if the shaft has rusted. You might need to use WD40 or similar to loosen it.

If you can take the faulty motor with you, that would help them, and you can also compare it in the store. You might write down model and serial number of your outdoor unit, and take that info with you.... just in case.

EDIT: and oh BTW, capacitors can hold an electrical charge once removed, even with the power off. Don't place your fingers across both leads. If could give you a small jolt.

cdcox
06-10-2011, 08:04 AM
Are you sure it is the motor that is bad and not just the capacitor?

kepp
06-10-2011, 08:20 AM
Are you sure it is the motor that is bad and not just the capacitor?

No, I'm not. How do I tell that? Place a finger across both leads? :)

cdcox
06-10-2011, 08:30 AM
No, I'm not. How do I tell that? Place a finger across both leads? :)

Your tongue will work better.

Easiest way is to look for any bulges. I think you can also use a volt meter, but I forget the details, so you better google it.