Hi,

I just want to confirm a few things by the pro's. My AC unit while installed in 2009, had its coil replaced in 2013 due to a leak. So its essentially only 3 yrs old.

I've got the following filter pictured below.. I've been very good in keeping it clean. Washing it out every other week, shaking as much of the water off it as heavenly possible, then re-installing it. The filter replacement size would be 22x24x1. As you can see from my coil in the 'before photo' , it was absolutely filthy. I was kind of surprised, given i'd been keeping on top of cleaning the filter and our house is clinically clean under normal circumstances. I'm going to switch out to those replaceable pleated filters, as i'm told they do a much better job at keeping the particles from reaching the coil.

I had a tech over yesterday for one of those radio advertised $29.95 services, and he said, there's no real way to fix this, other than a remove and clean the entire coil which would cost $1600. He could do a band aid fix, and spray it out with chemicals and flush it thru and brush what he can get off it for $300, but thing is that the mold / dirt could probably be really stuck deep in the fins and that would only partially help the problem. I asked how much would a new coil be, and well that was only $300 more than the clean. A mere snip at $1900 ?? so why go with a clean in that case. Another thing was fit a UV light and that 'could' help in killing the mold over time. That would be a $1000.

i just went ahead and took a shop vac to it this morning, and sucked out as much crap / dirt and mold as i could being very careful to not bend the fins. You can see on the after pic, there's a huge improvement, (despite a bent fin or two) and truth be told, cos of the flash it looks worse than it is, but even so its far from perfect. There's still dirt stuck in the fins.

I want to see what my other options are in terms of fixing this problem and giving it a better clean. Which coil flush am i better off buying. How did it get like this in the first place? Can i spray on the outside of the coil as well as in from the inside of the coil, is it safe to take an air hose to it or too risky and may bend the fins? I want as many opinions as possible, to make a proper call on this. It's a 4ton unit, fitted by the building contractor (new home in 2009) The coil was replaced under warranty in 2013 and didn't cost me a penny.

Should I clean by thoroughly spraying an indoor coil cleaner and then flushing it out with water? Will that be good enough of a job to fix this, or do i really need to have that coil pulled / replaced ??

Specs from the callout.

The temp split start was 64/78/14
The temp split finish was 64/74/14

Fan motor amps 3.6

Compressor amps 24.6

Fan amps 1.1

Here are some pics of my install.

Before


After i took a shop vac to it.


My filter


Actual unit


Condition of blower


Outer side of coil 1 which correct me if i'm wrong, doesn't look too bad.


Outer side of coil 2


other area's of the unit.










Appreciate the help on this.

 

First thing is don't let that tech back in your house, what a crook. $1000 to put in a UV light???? No way. I would pull the blower and clean the blades. For the coil go to Home Depot and buy some evaporator cleaner, no rising is necessary.

Get rid of that filter and install a pleated filter.

 

Never really done anything on an AC unit before. Is pulling the blower an easy job? Obviously i'll kill the electric before messing around in there

 

Due to the almost constant heat and humidity in Florida your coil does probably need to be pulled and cleaned to get all the way inside the coil. I think $1600 is an insane price. A more typical price would be between $350 and $550. Average price for a UV light would be around $275. That come on add that you answered are usually just a scam. A solid reference from someone you know might serve you better.

 

Your blower would be easy compared to some I have pulled.

Ditto on what theapprentice said!

 

Was wondering how far the return ductwork runs from the unit to the filter grille? Does it run through a crawlspace or how is that set up? Just seems like an excessive amount of dirt buildup if the filter has been changed and the house is kept cleaned. You might have a separation in your return duct that is allowing dirt to be sucked into the system from the crawlspace?

 

As far as cleaning the coil I would leave it in place you can see from the pics that it is partially accessible. (I have cleaned coils in much tighter places) First use the nylon brush attachment on a small shop vac to carefully vacuum as much dirt from the fins as possible. You may need to make a water catch pan for underneath the coil I like to use the aluminum turkey baster pans just measure the opening and get one that kinda fits you can bend the edges to make a good snug fit if needed. Now mix the evaporator coil cleaner at the strongest level on label and spray on liberally let it soak and use a soft bristle brush to gently brush the coils keep sprayed with cleaner and work your way across every inch of the coil. Then rinse the cleaner off thoroughly into your catch pan. I like to use a garden sprayer with pure water to rinse with that gives you much more control than a water hose blast LOL. Keep a close eye on your water catch pan and empty as needed. You may have to repeat the process 3 or 4 times to get a perfectly clean coil. Once done mix the evap cleaner in the weakest form per label that makes it safe to spray and leave on the coil, spray on and start unit and let the evap condensate water do the final rinse. Sigh now for the safety ****s. YOU CAN BE BLINDED BY COIL CLEANER ALWAYS WEAR EYE PROTECTION AND FOLLOW PRODUCT LABELS TO THE T If you do not feel comfortable doing this then interview a few service guys until you find one that has some sense LOL Good Luck

 

Ive just picked up some Pro-Green from Diversitech. It says dilute 1:3, spray into the coils from the bottom up.

I was going to do the outside of the coils, as there's not much dirt visible on the outside side. Mainly all on this inside.. So my theory is if i spray from the outside, it shouldn't blast anything further in.

Or am i just as well to spray on the inside as well. It may work in my favor and dislodge, or worth against me, as in push the dirt further in. Either way i've got enough here for three gallons, so i don't have to go easy on it..

Also am i best off given the dirt levels not diluting at first and just going for it, then rinse with water. Or should i definitely stick to the 1:3 dilution.

 

Your best bet is to spray the under side of the coil. Then run the AC and that will rinse it off.

 

Never use the chemical full strength. Most will give you different dilution levels with 1 part chemical 2 part water the strongest that has to be rinsed off and 1 part chemical to 4 parts water for the weakest which can be sprayed on and not rinsed off. I would mix at strongest level and spray from bottom and soak it good then spray from top and let it soak through the coil all the way. It will take several applications no doubt. Did you get your return ductwork repaired yet?

 

I think my ductwork is probably fine. The sealed closet that the handler sits in, certainly is fine. No holes or anything as such. I have recently been installing some wood flooring, which involved sanding the subfloor, and there was an incredible amount of dust. All of which got sucked into the ducting and AC. I also had some tiles removed via an angle grinder. So that made a lot of dust. The closet did have a film of dust on everything, after all the subfloor sanding... That was my mistake to not turn off the AC.

From now on, i'm turning off the AC system before doing any dusty work. I'll get this clean, change to a pleated filter 22x24x1 is what size fits in there, and keep my eye on it..

i have enough solution for 3gallons. So can do a good few rinses. Here are some other stats from my install

The temp split start was 64/78/14
The temp split finish was 64/74/14

Fan motor amps 3.6

Compressor amps 24.6

Fan amps 1.1

Here's a pic of the unit.