Check out some similar questions!

rockysdad1 · Nov 4, 2009, 05:20 AM

Hi, I have a Bryant 93% efficient furnace (2 stage motor) that is about 7 years old... the problem I have been having is that the furance won't start... the thermostat is set at 70 and the current temp in the house is 64! Whenever you turn the furnace on, the blower fan motor hesitates ~ you can see it whenever you pull the aor filter out ~ it kind of turns in quarter turns and stops and turns again... almost like it's hitting a dead spot or something on the motor... at first it would fire up after a few tries, but now it won't at all... I tried the external power switch and again it worked at first but now no luck... the code says "ignition lockout" and refers to how to basically clean the ignitor... would that cause the problem with the motor turning like that? Before it got worse, it sounded like the furnace would turn on, but there was no heat coming out of the ducts... I had one service guy say it "might" be the blower fan module, but he wasn't sure... he also said that you could not get that separately and had to buy the motor and the module as one unit... any ideas??
Thanks!

hvac1000 · Nov 4, 2009, 10:16 AM

The dirty flame sensor has basically nothing to do with the blower motor. If you have a variable speed motor the motor is available separately from the electronic end bell that is on that motor.

Caution!! Make sure you hire a service person who knows his business about the variable speed motors or you will be a sorry person with a HUGE repair bill. The variable speed system is not user friendly or user serviceable. You will need to contact the correct professional to repair it OR just start replacing very expensive parts. Just a heads up.

Note you can clean the flame sensor yourself. Steel wool or sandpaper will do the job.

rockysdad1 · Nov 4, 2009, 12:57 PM

HI HVAC1000,
Thanks for the info... I'm not at all educated in this field... so, the electronic bell end that you're talking about, is that the same as the motor module?? Also, would I hire a person that deals strictly with Bryant furnaces? I was told that Bryant and Carrier are basically the same units, just different label put on them... it that an accurate statement? So, the first thing I should do is clean the flame sensor..? I came home and now my house is a brisk 62 degrees, so obviously the furnace isn't working at all... I was also told by another person that if the gas pressure is too low to the furnace, it won't work... is that true?? I don't know why the pressure would be low, there has been no changes made at the house or service done by the gas company...
Appreciate ANY advice...
Thanks!!

hvac1000 · Nov 4, 2009, 04:01 PM

Try cleaning the flame sensor
Yes Bryant and Carrier furnaces are the same unit for unit.
Nothing you can do about gas pressure so call a pro if the flame sensor trick does not work.
There are 3 main parts to the variable speed blower setup. Circuit board, motor and motor electronic end bell.

rockysdad1 · Nov 4, 2009, 04:10 PM

HVAC1000, Thanks for the response... I've tried the external switch thing again and its not working at all now... doesn't appear the ignitor is even lighting... I don't see anything through that window... my thermostat now tells me to change the filter, so I got to go get a new one in a few minutes... house is at 62 degrees... any other ideas..? Appreciate your responses... got a little child in the house...

KC13 · Nov 4, 2009, 05:15 PM

Check the service label for the procedure to display all stored fault codes. See if any codes 41-44 are displayed, as these are relative to the variable-speed motor. Most problems with these are due to a faulty module, and YES it is available separately from the motor. There are 3 different modules, dependent on the horsepower of the motor you have. The part number will start with "RMOD" and be followed by the numbers that identify which motor it is intended for. They are a li'l pricey, so don't jump to conclusions. If you have a voltmeter, I can describe for you the troubleshooting procedure to verify that the motor is OK.

hvac1000 · Nov 4, 2009, 05:38 PM

I will post some goodies about variable speed but if you are around KC13 jump him through the hoops. Had a confrence call today on some boiler controls and I am flat worn out.

rockysdad1 · Nov 4, 2009, 08:26 PM

Hey Guys, I appreciate all the help!! I will see about getting a voltmeter and get back with you guys tomorrow... my neighbor was able to clean the ignitor and we got it to fire up and its running for now... he thinks part of the problem is the goofball who install this furnace 7 yrs ago, sold me a furnace that is 20-40,000BTUs small than what I should have, plus he got 1 1/2 " PVC for the intake and exhaust.... he said it should be atleast 2"... I appreciate you guys helping me out!! I got the house up to 69 degrees right now! :) Thanks again guys and I'll check back with you...

KC13 · Nov 5, 2009, 02:32 AM

Sounds like you have a good neighbor (I don't mean State Farm). He is right on about the venting. I'm surprised it hasn't been a problem until now. I hope Goofball Inc. isn't still in business...

rockysdad1 · Nov 5, 2009, 07:37 PM

KC13 & HVAC1000, here's the latest saga... I had my brother's buddy come over~he does HVAC for a living... my house is about 1600-1700 sq ft... the furnace that is there now is 60,000 BTUs. This guy said I should have 100,000 BTUs... is that true ? I know whenever it was replaced 7 years ago, the original furnace was 80,000 BTU... Goofball Inc also replaced all of my ductwork throughout the house ~ I had to gut the house there was mold in it, unknown to me whenever I bought it... Goofball installs 8"x10" ductwork... this guy told me that this is not the correct size and that it is probably half the size that I need for the furnace... further yet, I got a 2 ton AC unit and this guy said I should have 3 or 3 1/2 ton... is this all true?? I mentioned yesterday that Goofball installed 1 1/2" PVC out & into the furnace... this guy told me that between the small PVC, the small ductwork ~ my furnace is starving for air and that could be the reason for the motor module problems... sound right?? I know I was stunned whenever he told me all of this because I paid Goofball Inc a ton of money and no to mention the drywall guys that put up new drywall all through the house, only to hear this guy say I need to rip the ceilings down so new ductwork can be put up... any suggestions guys?? I mean, as you can probably understand, it's hard to find anyone to trust about now ~ you don't know who is just trying to make some more money from me... it's frustrating... the furnace is still running as of now (knock on wood ~ LOL) and the house is 72 degrees... I was going to just let it go and see what happens... my brother's buddy said that even if I dump money into this small furnace, with all of the small PVC and ductwork, the motor would be straining anyway and it would wear out again... I don't know what to do... any opinions? THANKS IN ADVANCE ~ you guys have been very helpful...

hvac1000 · Nov 5, 2009, 07:44 PM

The only true way to find out exactly what size furnace you need is to do a manual J. Ask your brothers buddy to do a manual J on your house and if he does not know what that is run away from him like he has the plague. Also have him do a manual D so you can find out exactly what size duct work should be in your home for the main trunk,return air and all the smaller runs to all the rooms.

As I said before this is the ONLY real way to tell exactly what you need and since a possible mistake was already made on this house you do not want to compound the issue and make the same mistake again. I know of homes that size that will heat with a 60,000 BTU unit but that does not mean your will. Unless you do a manual J anything else is guesswork.

Joshdta · Nov 5, 2009, 07:47 PM

1600 sf, is one floor underground? Should be about 80,000 btus and a 2.5 ton. The 8x10 is no way big enough, does it run both directions or just 1 way?

KC13 · Nov 5, 2009, 08:09 PM

While you're at it, perform a "Manual M" to find out how much money is in your bank account... :rolleyes:

T-Top · Nov 5, 2009, 08:11 PM

Sounds like you have a variable speed motor instead of a two speed. The duct coming off the unit should be small than get larger right after the furnace. This keeps back flow cfm from coming back on to the blower wheel which would cause the motor to hunt for a speed. In short variable speed motor bouncing back an forth bad module and or motor. Major bucks.

rockysdad1 · Nov 5, 2009, 08:27 PM

Joshdta, thanks for the reply... yes, the ductwork runs both ways... the middle of the house from one side to the other... which is 54 feet total?? Yes, the game room is underground... 26'x15'

KC13 ~ there is about $13.27 in my account!! LOL...

T-top, yes, it is a variable speed motor... the cold air return duct is 8"x14" & like I said the heating duct is 8"x10" Yes, I'm finding out about the expense!! This SUCKS the furnace is only 7 years old... I was quoted about $1400 installed for motor... I was told by the first guy that came here that the module was not sold separately and I had to get the motor with it... I don't know...

ANY other opinions are appreciated... like I said, I'm not educated in this stuff and I'm sure it shows... thus the reason I got ripped off in the first place...

THANKS much guys!!

rockysdad1 · Nov 5, 2009, 08:27 PM

HVAC1000 ~ thanks for the info about the manual J.

KC13 · Nov 5, 2009, 08:34 PM

Sorry to say it, and I hate to be the one to overstate the obvious, but you are in a bit of a bad spot. Spending a lot on repairs for a unit that may not be in your long-term future is impractical, but Winter is a-coming... does the furnace rating label list the horsepower of the blower motor? If so, I may be able to locate a good used module for you as a stopgap measure. I would only ask that you cover the cost to ship it to you.

T-Top · Nov 5, 2009, 08:42 PM

It will take away the seer value of the system but a normal direct drive blower motor can be installed with a relay for a fraction of the price. If you have just one 8 X 14 duct for the return air I don't under stand how you put up with the air noise, the variable speed is designed to try and move X amount of cfm no mater what, it ramps up when restricted.

rockysdad1 · Nov 5, 2009, 08:44 PM

KC13, Thanks, I would appreciate that... where would that be located ~ inside the door/front cover on the left side of the jamb??

rockysdad1 · Nov 5, 2009, 08:47 PM

T-top, the noise really bothered me much... I could hear it ramping up through the vents... I can hear the fan wheel wobbling... whenever it starts too!! LOL... so far it's working... I'm afraid to do anything to the furnace where it would stop... LOL...