DIY Home Improvement Forum banner

Post HVAC Check

4K views 42 replies 8 participants last post by  beenthere 
#1 ·
So I got my two 17 yo comfortmaker units checked today. The tech revealed to me that for one of the units, the refrigerant had low pressure and the coil is rusty and starting to ice.

He said the leak detect would cost $315 and replacing the coil almost $1800. He said most customers opt not to perform the leak detection and go with the assumption that the leak is in the coil. My thought is that this makes sense if the coil is old and rusty and you hedge that the leak will be addressed by replacing the coil unless by next season you get another low pressure reading with the new coil whereby you need another expensive recharge after performing a leak detect.

Also, the 35/3 capacitor is needs replacement (still in range) and the compressor is drawing current just below the high threshold that's labeled on the unit.

Given that, he recommended that since my unit is so old, my money would be better spent going with a new system. He recommended Carrier and said they come in 3 cost points, the base, comfort, and infiniti.

For the record, I usually have the thermostat set at 82F and the unit doesn't run that much. The unit is in the basement and the tech emphasized how the ice could damage carpet.

I was told that peak cooling season in the mid atlantic region is late july and august, and better deals could be had if I performed a replacement right now in early July or in between cooling and heating season like Fall or early spring. My thinking is to possibly replace the unit but hold off until Fall.

WWYD?
 
See less See more
#4 ·
Do you get them checked once a year?

If it is a slow leak that took several years to get bad enough to affect the cooling and you live in the US he can top up/add more freon. If it is a bad leak and needs a refill every year then we can discuss replacement. In Canada we must find the leak and repair it/not top up and at that age nobody here will do expensive repairs as the compressor is worn and lost capacity.
 
#7 ·
I haven't had my two systems checked for awhile. I signed up for the maintenance plan last winter b/c one of the units was making a noise. During the diagnostics, he determined that the blower wheel fins were rusted and dislodged and the blower wheel needed to be replaced for $350. I ended up finding the wheel myself and replacing it for part cost of $125.

So, since I signed up for a maintenance plan, he was back this spring/summer. Prior to that, the last time I had a recharge was about 3 years ago. The price of freon has gone up.

Back then it was $90 for the first gal and 1/2 for the next gal. Now, he quoted me about $450 for first gal.
 
#2 ·
If the capacitor if within tolerance then why does he want to change it?

It's true that a good portion of leaks are in the inside coil but not all. You can look yourself by looking for oil stains on the pipes, coils, or around the compressor inside the outdoor unit. If you find a spot, squirt some dish soap in the spot. If you see bubbles, you've found your leak. If it's in the coil, it's not worth fixing at that age.

I can only assume that you and/or the tech actually checked the filters, and made sure that their clean.

Fall and early spring are the best times for replacement, or other significant work. However, locally, the past several weeks have been very spring like, techs are starving so deals are very good atm. (Ontario, Canada) I would ask for a second or third quote on a new system. Only tell them that you're looking to replace. You wouldn't want to pay another service call fee.

Cheers!
 
#5 ·
Verbally, he told me the capacitor is still within range, but in his writeup, he said he recommended change.

He did talk about oil stains in that if there are no oil stains in the joints, then most likely it's a leak somewhere. I did not note any oil stains in the joints.

What color would the oil stains be?

He said if the leak is in the coil, then they recommend replacing the coil for $1800.

I always check the filters and so did he and the filter was replaced.

Here in the midatlantic, it has not been that hot, but I figure by the time I get 3 quotes, it'll be into peak, hot cooling season. I'm thinking if I want to replace that once I get past the cooling season, I'm good into the next cooling season, so I would have about 7-8 months to figure it out.

The furnace works just fine.
 
#3 ·
Starting to ice ? As has been said , could be lack of air flow / dirty filter . Or low on refrigerant .

As far as rust , the frame may be steel . The coil should be copper with aluminum fins . Not as prone to " rust " .

I agree , if the dual capacitor is within specifications , why replace it ? If concerned , buy an new one for a spare , they are not greatly expensive .

Sounds like he / the tech is trying to drum up sales .

How is the system cooling , now ?

God bless
Wyr
 
#6 ·
He did say the refrigerant was low. Good point on the "rust" observation. It is copper.

The system is cooling fine now for my needs, but he said the inlet vs. outlet temperature is not within specs. As I said, I set the thermostat to at 82F and it's the downstairs unit.
 
#8 · (Edited)
The oil stain biz is a bit of folklore. You need a large leak and I only see them 5% of the time with leaks. More for refrigeration units. Soap bubbles don't really work for freon as you need a special Nu Calgon gas leak detector soap which gives off huge bubbles with tiny leaks. Dish soap is good for natural gas leaks but does not cling to the joint and runs off too quick with freon.

You coil is not worth replacing as it is a 8-10 SEER and obsolete and the replacement is 13 SEER and a mis match. Too make it simple if it is cooling keep using it for another 3 years. If it needs a refill of over 1 lb next year then it has a big leak and then I would buy a new unit.

Techs are selling techs and get a good commission and it is our job to give advice. Nothing wrong with that. However not every unit needs replacing unless it needs very expensive repairs. If you can refill it and want to try get another 3 years use out of it I would. People use ACs for up to 30-35 yrs. If you are in Texas or Florida then you want a more efficient unit but if not then using a old one and paying another $50-100 for electicity a year is a lot cheaper than buying new.

Freon is sold by the pound not gallon. R22 is expensive and can be $50-75 per pound. All depends on what you are comfortable with. Don't get conned into believing your unit is junk as you can get more use out of it. All depends how big the leak is and whether you want to invest a few hundred $$ in refilling it.

It is not good for the environment to leak it out and some people are concerned about that. All depends on what side of the moral fence you sit on.
 
#9 ·
You can look on the name plate of the condenser & should be able to find the data on how much refrigerant the unit contains , usually in ounces , but maybe in pounds and ounces .

If it is cooling fairly well , use that as sort of a guide line on how much he says he has added .

Do not let some one sell you new equipment bases solely on the cost of replacement R22 . It is cheaper than new equipment , unless you have a good size leak . Sometimes leaks can be found and repaired . Sometimes not .

God bless
Wyr
 
#11 ·
Get the leak found and fixed - leaks are bad for the equipment (running low on charge and moisture introduction), your pocket book (higher energy use, top ups), and you and I...



 
#12 ·
I do find leaks about 3/4 of the time by looking for oil stains. They may be very faint though, so it helps to have the very good eyes of a young lad. It'll look like a wet spot that doesn't dry. It probably won't feel oily either. It's more likely to leave a strain on the high side then the low. While i do use nu-calgon, i was trying to keep it diy. When dish soap is not diluted, some brands sick quite well. It won't find the smallest of leaks, but will find larger ones. It's all about trying to avoid the leak detection bill. Cross your fingers and look hard. If you do find it somewhere easy, you can have it fixed much cheaper then a new coil

Cheers!
 
#25 ·
EPA 608 cert doesn't really go over anything technical enough to help much with a system. Mostly history of events. Plus recovery levels for different equipment and machines.

You know the hole in the ozone layer was actually found in 1929(before HCFCs were invented). But in the test, its listed as 1974. Other wise it wouldn't make sense to phase out R12, R22, and R502.
 
#27 ·
Has anyone witnessed or know the reason why the air handler, when not running, in the morning would sometimes give off a sound that's similar to a brief rapid fire rumble...almost like a machine gun sound?

It doesn't occur consistently and seems to be coming from the coil area. Also, it seems to have happened when the system was switched off in spring and when the system is on (but not running due to thermostat setting is higher than room temperature) in the summer.

I'm wondering if this is related to the expansion and contraction of the freon based on outside temperatures?
 
#29 ·
No idea , other than some smart mouth remarks that probably would not be helpful .

If it was happening more consistently I would recommend buying a cheap mechanics stethoscope at Harbor Freight and try to narrow down , more closely , where the sound is coming from .

Is the exhaust / vent from the furnace open , on the roof , so birds can get in ?

God bless
Wyr
 
#32 ·
Reminds me of a phone call I got on a sunday a couple years ago....

Go give a neighbor a quote for replacing her system.....get a call a few weeks later on a sunday morning: some sidejobber's equipment broke while he was putting in her new system on the cheap on the weekend.....the question was: "can he Borrow your equipment today?"

She also complained about what I would charge to come on a Sunday to USE my stuff.
 
#33 ·
I got a call yesterday afternoon . I was taking a nap .

The caller was a guy that works maintenance ( mostly HVAC ) for a company & we do service & construction for that same company .

The apartment complex he lives at ( on the 2nd floor ) is having problems with a sewage ejector pump . They evidently have changed pumps and are having problems getting the wiring to work .

The submersible pump has 4 wires in the cable and the apartment maintenance man can not get it to run .

I asked the guy I know if he has an ohm meter ? No , he did not bring it home from work .

Anyway , I told him I would come over & help , free , as a favor .

The pump room is bad , just about beyond imagination . :-(

One pump was single phase 208 VAC . The other was 3 phase 208 VAC . Got both to run , but the 3 phase pump was no good . The single phase pump would run but the control panel was not working right . Would not cycle properly or do lead - lag .

No fixing it on the weekend . I suspect it needed a circuit board , IF the floats were OK . Did not volunteer to mess with the floats . I leave that job for plumbers .

The maintenance guy was happy . The guy I know is happy . And I am sure he will call the company I work for , every time he has the slightest opportunity .

I got home in time , yesterday , for supper . :) For which I washed my hands VERY well .

God bless
Wyr

PS Now I can call him if I have HVAC problems I can not DIY . :)
 
#37 ·
To give him the benefit of the doubt , he might have been OK if he had a meter with him .

On the one with 4 wire cable , black , red , white & green , first thing I did was establish the green did not have continuity to the other colors . I then established that the other 3 colors had continuity between them .

The other pump had 3 wire cable black , white & green . Continuity between black and white , none from either to green . They told me the pump was 240 VAC ( supply was actually 208 VAC single phase ) .

I had no way to determine rotation om the 3 phase pump . Would not pump either direction of rotation . But the motor ran .

Did not run it either direction very long .

God bless
Wyr
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top