Hi,

My indoor blower quit working, first it made weird sounds during start few times and then quit. I have a Rheem Criterion furnace from 1992. The air handler and evaporator was replaced few years ago and other maintenance done.

The run capacitor (Old one was a cylindrical 15MFD 370VAC and new one is oval GLOBAL 2010 15x370)was replaced yesterday night and fan started working after about 20-30 secs. We were very happy. We just came back from dinner and it has died again.

Blower control board from other unit was tried but motor just hums like it did before new capacitor.

Should I get the fan relay replaced? What seems to be blowing the capacitor? I have already had couple of service calls in month and would like to get this fixed good at least for one season.

Thanks for reading and any suggestions.

ulbhpy

Hi,

My indoor blower quit working, first it made wierd sounds during start few times and then quit. I have a Rheem Criterion furnace from 1992. The air handler and evaporator was replaced few years ago and other maintenance done.

The run capacitor (Old one was a cylindrical 15MFD 370VAC and new one is oval GLOBAL 2010 15x370)was replaced yesterday night and fan started working after about 20-30 secs. We were very happy. We just came back from dinner and it has died again.

Blower control board from other unit was tried but motor just hums like it did before new capacitor.

Should I get the fan relay replaced? What seems to be blowing the capacitor? I have already had couple of service calls in month and would like to get this fixed good atleast for one season.

Thanks for reading and any suggestions.

ulbhpy As long as the mfd and vac is the same it will work no mater if one is round or oval. If you get a loud hum from the motor and its not starting you have a bad blower motor(thats if the tech replaced the run capacitor). Most companies will give you a labor warranty if they did not fix it but the cost of the blower motor will be on you. The run capacitor should be changed out any time the motor is. So if the motor is changed out you need that new capacitor anyway.

I will add to the above that it is a good possibility that the capacitor was not bad but that the motor had gotten hot and cut out on the internal overload and by the time you had replaced the capacitor it had cooled enough that is started when you turned it on. But after it ran for a while the motor over heated again making you think the capacitor had blown again.

As long as the mfd and vac is the same it will work no mater if one is round or oval. If you get a loud hum from the motor and its not starting you have a bad blower motor(thats if the tech replaced the run capacitor). most companies will give you a labor warranty if they did not fix it but the cost of the blower motor will be on you. The run capacitor should be changed out any time the motor is. so if the motor is changed out you need that new capacitor anyway.

Thanks T-TOP for your quick response. Do you think I should replace capacitor again before getting a new motor installed as it is a easy one. In other words do these new capacitors go bad sometimes really quick in a day

I will add to the above that it is a good possibility that the capacitor was not bad but that the motor had gotten hot and cut out on the internal overload and by the time you had replaced the capacitor it had cooled enough that is started when you turned it on. But after it ran for a while the motor over heated again making you think the capacitor had blown again.

Thanks for the analysis. What happened was the blower died Monday sometime. I turned off ac unit and tried as late as Wednesday without success (motor hummed). Had capacitor replaced Thursday night and it started working. It died by today (Friday evening). Same symptoms. I can hear the motor hum pretty loud again.

I will try to turn it on again tomorrow morning after it has cooled down. If it starts I will get motor replaced since it is overheating.

Replacing motor will solve your problem

When and if you do change the motor make sure that you replace the capacitor with one that is rated for the new motor. Good Luck.

Thanks to all you. Motor is confirmed bad. But the motor has three mounts screwed to it. It is 110v 3/4 HP 1075rpm motor. It is not available locally in Dallas today because of mounts. Internet quote is from $300 with S&H. Any suggestions? I can get the spec motor, but screwing in mounts seems to be problem. Drilling holes for screw is good or bad?

Of course a 3/4 HP motor is higher that a 1/2 or 1/3 but $300 does seem a little bit high. I think I would do some checking around before I bought. Another thought is that some places have motor mounts that will fit many different mounting situations.

Maybe get a recue motor and a mounting ring. Should be much less than 300

I found a.o.smith ORM1076 motor at Tolberts Electric in Garland, TX for $143 with tax. Online best price was western Nevada at $200.

I installed it myself last night and everything (touch wood) is working so far. Getting old motor out is not easy and requires you to remove exhaust flume cover. Motor with squirrel cage is quite heavy. I cleaned cage with water hose. If you attempt to do this, make sure you read your furnace instructions as it will tell you how to take out a panel to allow easy removal of blocking exhaust pipe. Take pictures before and after, or you will be wondering like me (where does this screw go? ). When you mount motor on cage make sure cage is centered before you tighten bolt on motor shaft or it will rub on case with loud noise. This exercise also made me aware of importance of regular quality filter change. I am finding pleated filter buckles and lets dirty air through edges.

Thanks Ask me help desk for this fantastic forum. My hearty thanks to all of you who took the time & effort to answer. I do wish parts are less expensive.

Glad you got everything going and you are now cool. You are right, this is a great forum