Coil Cleaning

[FILTER MAN]

What is the best way to clean an industrial coil, say 6"-8" thick. High Pressure or low pressure high volume?

[fearlessfurnace]

pressure starts bending fins pretty quick. so low pressure high volume.

[redcell09]

I like to spray coil cleaner on and then run he fan to pull as much cleaner into the coil as possible.

[mixsit]

I settled on 1/4" 'fire nozzle + an in-line ball valve. This year I tried the booster pump on the hose cleaning the 30 ton Liebert coils (horizontal, 4-fan units deeper than the 8-fans). Going from 'city pressure about 12-18# static to around 40+ got me 20+ flowing with the 1/4". That cut the time quite a lot.

On deep coils I look at it like the impedance problem of a hunting round. 50Gr .222 against a bear (PO'd bear with mucked up coat ..vs similar energy from a slower heavier round.
IMO it comes to a balance of appropriate velocity (fin damage being the limit).. at as much flow as you can get. That and adjusting your attack to what works for that coil.

[lynn comstock]

• I believe in backwashing as much as possible so the dirt leaves the way that it came in.
• I like to back light the coil for inspection so that the clean and dirty areas can be identified and progress evaluated.

[timebuilder]

I use the greatest pressure I can while avoiding any fin bending.

I agree that on the thicker coils you can make a lot of headway by washing from the inside toward the outside. The 4" slab coils on the lowboy Carriers and the 6" coils on the old Lennox Epic series are the most challenging.

30% mixture of nu-brite and water, rinse and repeat till nothing (clumps and dirty water) come out.

[boilerman856]

Has anyone tried using steam? I think I am going to get a small unit for the rooftops.

[mixsit]

• I believe in backwashing as much as possible so the dirt leaves the way that it came in. ...

Good point there. On the thicker Lieberts for example I'd always go 'face skim the cotton wood' off, rinse from above, below and above again as need.
On the thicker 4-fan units I found using the fans to help agitate the flush up into the coil from below worked very well. The same on the 8-fan’s.. = dirt bath.

[amickracing]

I washed a couple liebert decks with a pressure washer...
I thought I did a good job, blew the worst off from the bottom (entering side), then rinsed from above with a light mix of simple green in combination with the pressure washer.

Rinsed from below after a good dousing from above.
Some reason as I was rinsing the bottom I left the nozzle pointed in one area for about 15 seconds longer than normal... and black... black black black crap came pouring out. I was against the clock a bit (2 units, one could be off around 1-1.5 hours before things started getting warm, so I was under the gun). Kept rinsing like that, holding pressure in one spot until it got clear then moving on. When I was done (probably 60% done if I could have taken longer), and the concrete was smooth with all the black junk that came out.

I was hoping to get to clean that contract this year so I could finish what I was doing, but... our new guy got the job (ok, I'm not all heart broken he got all the coil cleanings this year).

I say pressure, as much as the coil can stand, with a decent volume is the key, and while I'm not a huge fan of harsh chemicals, I do think they help when the coil is very dirty, greasy, or you can't blow through it (thick coils).

[lynn comstock]

....the concrete was smooth with all the black junk that came out...

To think that that all came out of the air that we breathe. EEYUK.

[mixsit]

I washed a couple liebert decks with a pressure washer...
I thought I did a good job, blew the worst off from the bottom (entering side), then rinsed from above with a light mix of simple green in combination with the pressure washer.

Rinsed from below after a good dousing from above.
Some reason as I was rinsing the bottom I left the nozzle pointed in one area for about 15 seconds longer than normal... and black... black black black crap came pouring out. I was against the clock a bit (2 units, one could be off around 1-1.5 hours before things started getting warm, so I was under the gun). Kept rinsing like that, holding pressure in one spot until it got clear then moving on. When I was done (probably 60% done if I could have taken longer), and the concrete was smooth with all the black junk that came out.
...

Fairly key point to come out of the notion of 'cloil cleaning' in regard to deep coils there. The amount of time, water, flow, penetration coverage involved with actually getting the stuff flushed out vs 'Yeah we washed the coils'.
We've been bit with V' frame Tranes for example. If you're not taking the sides off and getting in from both sides, sure they look good.

[darkbeekeeper]

I use a steam cleaner it works well on most rtus but it is not the answer for all units. i brush them off use the water hose then hit with steam. with steam i dont have to use chem and i have more pressure without the fins bending. I was cleaning indoor coils with cans of cleaner and after about the tenth one the cook had asma attack i went to a steam cleaner after that the best 3 grand i ever spent its paid for its self in time, chem and easy of use i love it

[fearlessfurnace]

To think that that all came out of the air that we breathe. EEYUK.

I have devoloped a device consisting of a tube that directs the air to two bags that remove and trap all impurities in the air.

what are the bags called?

lungs