Contactor buzzing on condensor unit, was $128 replacement a good idea/price?

[jymusic]

My mom and I both live in the same complex. We likely have the same exact model of central A/C condensor (around 19 years old). Mine says Carrier

38EN048320.

We both had a tuneup scheduled and, in addition to the regular tune-up, the technician recommended the EXACT same extra work on both our units, which makes use wonder if the extra work was really necessary and the price was really reasonable.

On mine, the maintenance technician showed me that the contactor was buzzing. The old part says "8726 Honeywell R824381247 (3) 24V 50/60ZH HN51DC024A"

He also recommended putting in a condensate trap, which is a clear U shaped trap in the condensate line.

I went along with it and let him do both jobs and so did my mom.

1) Was wondering if the contactor making a buzzing sound is really a problem? I don't know much about these, but the two "circular metal (silver?) pieces" on the old contactor do look like they have some grime or maybe carbon on or oxidation. Does the buzzing mean the electromagnet is struggling to pull the piece against the "metal circular (silver?) pieces" to make a connection? Was $128 a good/fair price for replacement or too high? I see he wrote down that he put in "a 2 pole 30a contactor"...the original was 24a...was 30a really necessary?

2) Is the "ez flow P-trap" condensate trap is going to be of much added benefit? Was $99 a good/fair price for installation or too high?

3) By the way, wondering if you any can tell me how many tons my unit is, based on the model number?

Thanks,

J.

[RBM]

It's really hard for anyone out here to judge the necessity of part replacement without seeing the part. If the contacts are not being pulled in completely, because the contactor is worn out, it could damage the motor. You have to have some faith in service people. I think the guy is trying to do preventive maintenance. As far as his charge, I get $125 for a service charge not including parts

[cornytheclown]

Odds are 50/50 that you actually needed a part. A lot of residential hvac outfits demand that their employees sell so much in parts a month.

You just never know.....both you and your mom needing the same part at the same time...you were probably hosed....wait about three years from now and they will do it again.

[Edwin Pawlowski]

Hard to say for sure. At 19 years, the part may have been on the way out. When I lived in PA, we had to have our cars inspected twice a year (now it is only once). The shops all had a gimmick to make a few quick buck. We had three cars in our family and in one round, they all needed a headlight adjustment. Six months later they all needed wiper blades. Six months later, well you get the idea. Back they we were driving some real crapmobiles so it was cheaper to pay $2 for an adjustment rather than them find the worn ball joints that a reputable shop would have done.

[Doc]

Answers to your questions

1) Buzzing isn't necessarily a problem other than the noise. However, the oxidation could be a problem. I have seen some with a little oxidation get stuck closed and I have seen them completely black and still working. You can never tell when one will stick. I have had more stuck closed which means the condenser runs when there is no call for cooling. On the other hand they sometimes may not make proper contact which means no cooling. Probably a good call to replace it if there is any question at all. As far as the 24a and 30a. 30 is far more common most techs would not have 24 with them (I don't carry them). You would have had to pay considerably more for them to run out and get one. Besides that, with them higher amp rating the contactor may last longer. $128 is a fair price if that was in addition to the checkup price. If it was total price including the check up it is a very low price.

2) The trap was probably not needed, unless it the unit is a counter flow system or it is tied into the sewer stack. I doubt that either of these situations are the case. If it is a counter flow unit the blower can suck the condensate from the drain and keep it in the unit. If this were the case you would have had water around the system. If it were tied into the stack ( you can't do this in many areas) you would probably have had a sewer smell in the house without a trap. Traps have a problems with getting clogged, I often remove them for this reason. Hopefully a tee was installed before the trap so it can be flushed periodically to prevent blockage. Price to install the trap seems a little high if that's all that was done to the drain systems.

3) must be a large apt/condo unit is a four ton

[Ralph Mowery]

If the units were 19 years old and you did not need the P-trap for the first

18 years, I would say you have been taken on that at any price.

The contactor buzzing could be just some rust under the mating pieces or it could need to be changed to prevent it from going out later.

[jymusic]

This particular trap is clear so you can see if it is clogged, and it has two red lids that can be flipped open to clean it. The technician seemed to think that having a trap would cause the pan to drain out better than before, and claimed that there is is even now a code that NEW systems have to have it. Maybe it was a ripoff. I don't think my system is the kind that you mentioned, and no it's not tied into the sewer line.

Yes, 2100 square feet townhouse EXCLUDING the finished basement which has supply vents in it (although I usually close those since basement is cool enough in summer)

J.

[mm]

I was licensed in PA for a while. Twice a year was really annoying.

OTOH, Maryland has once when you buy the car and that's the end of it.

Keep the car for 20 years, never need inspect it again. (although if a cop sees you with a light not working, after you get it fixed, you have to go to the police to prove that you fixed it. I suppose the other lights better work then.)

Once I bought a new used car and had it inspected. A lot of things wrong with it, costing a lot of money. I went to another place and they found quite a few things wrong with it too, but none of the same things. I thought the second guy's list was more important and more likely to be accurate, so what I could do, I did, and the rest he did.

[udarrell]

You must live in an awful hot climate or an energy inefficient condo, under most conditions, four ton is a lot of cooling for 2100 sq. ft. Perhaps equipment is not matched to the ductwork, etc., for a lot of reasons those units are probably NOT transferring 4-ton of heat to the outside.

When it comes time to replace those units have an heat-gain heat loss done on those condos and do whatever it takes to reduce the size of your cooling and heating equipment ! Where are you located? - Darrell - udarrell

[jymusic]

I agree that a full analysis should be done when time for replacement. Wondering how much longer my 19 year old Carrier condenser is expected to last?

Maybe they originally included the basement in the calculations, but then again it wasn't originally finished. My townhouse is an end unit. Even the non-end-units have the same size A/C condenser as well. All the units have two skylights upstairs and there aren't a lot of trees to block sunlight.

Main problem with cooling is that one of the upstairs rooms that faces the south gets much warmer than the rest of house on sunny days. I actually wound up installing a portable (kind on wheels) A/C unit in that room to ensure the temperature in that room stays in the 70s. because there is only one zone and I keep the downstairs set to 75 during the day. Sometimes on a sunny spring day (mid 60s or warmer), I have to use the portable A/C in that one room while the rest of the house does not need any A/C.

J.