fan stopped in Lennox HS29

Old 06-01-09, 01:04 AM
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fan stopped in Lennox HS29

Our Lennox was installed new about 8 years ago, and has run well since. Recently, while still cooling some, the cooling hasn't been as cold as previous years. Checked it out, and the top fan isn't moving, so I suspect the capacitor.

Since it hasn't been serviced for 3-4 years, I suspect the charging needs to be checked, and possibly topped up by a pro.

Am wondering if I should try to save a few $$ by changing the cap myself (I am experienced with electronics, filter caps, safety).

Can any pro's give me estimates on A/C charging (checking), and/or capacitor replacement?

Of course it might be more than that, in which case I'll probably have to consider whether to fix or replace.

This unit mates up with a Rheem 80 that is working well.
Old 06-01-09, 03:42 AM
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HS29 is a condensing (outdoor) unit by Lennox. There are "3" more digits after the HS29 which you have reported and which help fully identify your unit (size, capacity, features, etc.)

The top fan you mention is the "Condenser Fan", and the fact you are reporting that it sometimes is not moving should be reason for concern and is most likely the explanation (NOT a leak as you suggest later) of why you do not feel the system is cooling as in previous years.

In this condensing unit, anytime the compressor is running (the component inside the black metal enclosure located below the top fan) I said, anytime the compressor motor is running, the condenser fan motor MUST ALSO be running. If this fan does not operate, or, operates erratically, refrigerant pressures increase and with them the refrigerant temperatures, which is why you do not feel as much cooling anymore.

Furthermore, if this malfunction were not to be corrected, you could end up with a compressor burn-out which is a VERY EXPENSIVE fix. DO NOT operate your unit until you have it fixed. You may have a defective dual-capacitor here, or even a defective motor (sounds like the bearings are on their way out).

One last thing, central a.c. systems are hermetically sealed, their lines (copper tubing) being brazed. They DO NOT need topping ever, not to mention every few years, so do not fall into that trap if an unscrupulous service tech tells you so. If refrigerant IS INDEED needed, you then have a leak that must be fixed prior to "topping-off" the refrigerant charge.
Old 06-12-09, 04:50 AM
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As pflor said you may have a bad cap, easy to check - do you have a meter and know how to use it?

As far as the charge goes, you shouldn't need refrigerant, if you do there is a leak. If you don't feel comfortable checking the cap call your local Lennox dealer and have them perform annual maintenance. That should identify and correct ant problems.

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