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95 TA - The Beast
06-27-2013, 01:59 AM
So, I have gotten around to taking care of most things around here and one of the last few on the list is the AC system.

Now, I have done all the normal stuff such as:

-Checkout the A-Coil (clean from the inside, as seen with a remote cavity camera from where the blower motor normally sits, yeah I pulled it, cleaned it out and checked inside the furnace plenum)

-Flushed and cleared out the A-Coil drain line (clear now as well as looking into the drain area of the A-Coil with the remote cam, boy is it rusty in there. I would expect for the price for those things to be made out of stainless)

-Removed the condensor cover/fan and cleaned out inside the unit

-Used a hose and sprayed out the condensor itself from the inside out to clear everything from the fins

-Straightened the fins on the condensor

Now since I have no clue if the previous owner took care of the unit (it is a Heil 3-ton unit made in early 2001), I am considering just replacing the contactor and capacitor out of a purely preventative maintenance perspective. Is there any issue in doing just that?

Both will run like $60 or so, including upgrading the contactor from the rated 30amp unit shown on a parts list to a 40amp MARS2 unit listed as a upgrade replacement for 35amp units (the model number parts list shows a 30-amp contactor, yet the label on the condensor shows a max breaker rating of 35 amps, so I figure going with the larger is just prudent), and the cap is a standard replacement OEM part. I figure even if the capacitor in it specs out fine, it is still possibly 12 years old, no sense risking it dying anytime soon if I am in there replacing the contactor. I figure the contactor is due regardless since even on the recommended 6-year cycle it is at that point.

I figure if I do all that then all I really have left to do is have someone come out and check system performance and the freon level and top it up. Anything else I am missing?

I will say balancing dampers in a non-zoned HVAC system with 3 levels is a PITA... I have good settings for winter, just need a couple more hot days to be happy with my settings for summer. Thank god I don't do home/away cycles and just keep the system set for the same temp 24/7, otherwise this shit would drive me nuts... If the house is empty during the day once the little guy goes off to school in 3-4 years I may just have to consider a multi-zone system or a dual-system setup as a major replacement/upgrade, but I am happy with my energy bills and the consistent heating/cooling of the entire house to the same temp all the time. I only really change the temp to 68-70 in winter and to 70-72 in summer. I may see how things go and do 70 year-round, but the slight bump in temp either way has to be better on the energy bills overall...

95 TA - The Beast
07-02-2013, 12:47 PM
Well, found out I had a hookup through a friend and had a HVAC pro come out and checkout the system. Turns out the contactor and the capacitor were both original. So the contactor got replaced and I ordered a new capacitor (the one in there spec'd at 37/3 and is rated at 40/3) and the system needed about a lb of R22. No idea if the system was originally short-filled or not, but per the specifications it read where it needed to be after the fill. I will check it myself again in fall and again in spring and if there is any difference I figure I will do a leak test, but for now the system is running in top shape. About the only thing I may do is order a new fan motor in a couple years, not because it is bad, but because it is a sealed bearing unit that you cannot oil, thus I figure 10-12 years worth of runtime is enough to no longer have confidence in it and I don't want to be down while waiting for a fan motor if it were to go out. Most AC systems are rated for 15 years or so, but considering this one sat unused for 2-3 years, I am hoping with good preventative maintenance and replacement of critical parts I can get upwards of 20 years from the setup. Since, as it stands, the newer units rated for the same tonnage are prohibitively big in regards to the condensor unit size. I would have to relocate it and all that jazz...

For reference, I could have done all of the tests and verifications, since AC systems are damn near identical between cars and homes (at least with fixed orifice systems, TXVs are more complex for testing), but I figured it was worth the piece of mind to have a pro check it the first time to make sure it was what I thought it was. Especially if you have a hookup with a pro, no sense doubting things. From now on I can do the testing and such, knowing it is what I read it is per the tests being done. Plus R22 isn't something the rest of us can just go out and buy without an EPA certification.

I also asked a ton of questions in regards to the rest of the HVAC setup and basically was spot on with my analysis and comprehension of what is what around here. Basically came down to the fact that this stuff is far from as complex as many pros want to make it out to be. Sure there are specific things to look out for with any system, but if you have someone to consult with to validate some of the conclusions you reach on dealing with things, then it isn't all that complex at all. Big key is don't overlook the small details and make sure you double-verify everything. Pretty much the same thing with anything important.

wrath
07-02-2013, 02:36 PM
The hard part about refrigeration is getting the EPA 608 or 609 (automotive) license and that is because it takes time. Literally any idiot can do it. Last time I did it there were only 100 multiple guess questions split into four sections requiring you to get 18/25 correct to pass... and that's to get a universal 608 license. Yes, that is correct, you only have to be 72% certified. haha. It might be more difficult than that, but I doubt it. If it were more difficult than that, I wouldn't see a bunch of idiots doing it for a living that other slightly less-than-an-idiot people come by and fix their idiotic mess.

It's $25ish to get an EPA608 Type I cert that lets you go buy refrigerant.

Talented individuals can do a job well AND quickly... and have decent troubleshooting skills. Most never get the "well" part figured out or else they'd have moved to industrial HVAC instead of residential. There are some people that think it's difficult and "costs $10k to learn" but they are the "any idiot" type. The expensive part of the whole operation is the refrigerant recovery (fairly expensive equipment, about a grand for a mediocre pump) and disposal (if you're lucky, you can find someone to buy recycled refrigerant for pennies on the dollar otherwise you pay to get rid of it).

There is a clown on the forum that is a self-proclaimed expert that does side jobs (or did he get shitcanned because his employer found out he was doing sidejobs?) that you can probably ask questions of that you probably already know the answer.

Blower motors that don't start and stop all the time that are in a temperature-controlled environment usually last forever.

95 TA - The Beast
07-02-2013, 03:15 PM
Blower motors that don't start and stop all the time that are in a temperature-controlled environment usually last forever.

Yeah, the whole house blower we have I have run non-stop since we get the keys to the place. Initially because the place was hot and humid (moved in the middle of last summer) and it did not have conditioned air run through for at least 2 years and with all the wood in this place I wanted to get as much moisture out of it as possible and keep it out. It took almost 3 months for the wood paneling in the basement (thick 1.5" real-wood finished chair-high paneling) to shrink back to where it needed to be as is pushed out a couple places on the longer wall sections.

Then I also wanted to get rid of as much dust/air-borne particulate that I could and was changing media filters once a month until about January. In January I picked up a set of electronic air-cleaner cells and pre-filters from a guy off craigslist for $50 for everything and got my electronic air-cleaner back up and running. I clean the pre-filters every month and the electronic cells every 3-6 months.

I have found I prefer the blower running 24/7 as temps seem quite stable throughout the house and the air quality is great. The big bonus, is as you mentioned, that the damn thing should last forever now that it is running 24/7. It is a 1989 AO-Smith unit, looks to be sealed bearings, otherwise I would be oiling them every year. They seems tight and everything works great, so I figure outside of PM stuff I am done on fixes/upgrades to the HVAC system itself. There is one place I would like to tap into an existing duct to get conditioned air into a closet in the front of the computer center downstairs, as it is all finished ceilings and such so putting in a new 6" run doesn't seem very feasible. I figured the tap wouldn't have to divert much of the pressurized air in that duct, just enough to keep airflow in the closet and allow for airflow out of the closet to the computer center. It would be stealing air from the front room upstairs, but that room has two dedicated ducts and they are both less than half-open in either summer or winter so I figure I have some airflow available to spare. The big issue is being able to tap into the duct above without much hassles. I know where to cut the ceiling, just haven't looked into the options available to cut into the pipe and put in a dampered vent.

Thanks for the heads-up on the EPA certification. I may just have to look into it if it is so inexpensive.

95 TA - The Beast
07-11-2013, 04:46 PM
Well, I figured I would continue in this thread instead of starting a new one...

In regards to the closet I mentioned I wanted to add a vent into, well I took another look in there, ended up actually scrubbing the two 6-8" areas that looked like it had some mildew staining (not mold or anything), then used the mold blocker spray stuff, then put the 70-pint dehumidifer in there, set it for continuous running, fan on high...

Well, a day and a half later I checked it to find it shut off because the bucket was already full... So I drained it and reset it back up, but this time I put a towel under the door so it can't pull in cool air from the room outside the door. Left it for 3 days, find the bucket 3/4 full. Drained it again and I have it in there running on high for a few more days.

I will say the temp in that room is really high (at least in the upper 80s, maybe in the 90s) because of the dehumidifer. Hopefully it is wicking all the water out of the finished wall spaces next to it (there is a bathroom that shares the one wall and even tho the closet is exposed foundation wall on the outside, the bathroom has a finished wall over the foundation).

I am just hoping this takes care of the moisture problem in there... I would hate to have to keep a dehumidifer in just that closet to make it useful... I am still thinking I may want to add that vent into that room to make sure there is no moisture problems in the future. With my running the whole house blower motor 24/7/365 I can't see there being a moisture problem if I do that.

Now, granted, there has not been any mold/mildew problems since I bought the place and dried out the lower level (jacked the electric heaters down there to 85 degrees and ran the dehumidifer for 3 or 4 weeks when we first bought the place, including keeping this closet door open, and I had the dehumidifer plumbed into the wet bars drain to keep from having to deal with the bucket filling up), but that closet always had a musty smell if you closed the door, which is why I kept the door open.

Could drying it out like I am doing be enough to not have to worry about it anymore in the future now that I keep the lower level heated/cooled with the rest of the house and because I am running the house blower 24/7/365?

Or should I also plan to tap into the duct above to get forced air through that closet?

I just don't want to store anything in there if it will get musty smelling. I personally can't stand that smell.