Replynever used pressure washer.Always got them clean with city pressure.I like to wash them myself then i know they are clean.Unless yearly thing then newby can wash them since they are not that dirty.
Professional Member
I worked at a place one time that had a portable steam jenny. We never used it on coils but everyone at work had sparkling clean engine compartments in their personal vehicles....
It wouldnt be much to get it on a roof. It was mounted on a two wheel dolly.....used a gas grill tank and a water connection....
I bet it would be great for restaurant rooftops or on some plants that spew a lot of grease or oil laden exaust out thru the exaust fans.
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Jonathan Lawson 2024
Professional Member
never used pressure washer.Always got them clean with city pressure.I like to wash them myself then i know they are clean.Unless yearly thing then newby can wash them since they are not that dirty.
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I like using the calgon foam gun. You pour the Nu-Brite into a plastic container that hooks to the water hose with a spray nozzle. Less chance of chemicals in your face when it is windy. Also it is easy to get uniform coverage on the coil with the Nu-Brite.
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Steam should never be used on a DX coil,What is the pressure of r22 at 212 F off the chart,than people blame the mfg's for coil leaks.Originally Posted by Gunn427
Professional Member
why would steam damage a coil? You are not exposing the entire coil to 212 plus steam. It is only a small section at a time so the pressure in a system probably wont go up. Relief valves pop. Also the pressure would have to be around what 1100 psi to burst? Brazed areas are the weakest and the internal pressure needs to be 1000+ psi. We used steam in cleaning coils for labs that have to be tested for any bacteria growth and not one single problem. Most coil leaks are the tubesheet rubbing from vibration and expansion and contraction.
Banned
The pressure of liquid and vapor in a sealed non running system is the pt chart conversion of the coldest or hottest point in the system.You are also expanding the copper tubing that passes through the steel tube sheet,which expands at a different rate. 1100psi in one of our coils yea right!!!! Trane says not to steam clean!!,I have seen it in their IOM's
Professional Member
Like I said you are NOT exposing a large part of the coil to steam so you are fine. If it is done properly you will be fine. This lab we work at demands it and this has been done for years with no problems. Just like so many things we do, if it is done properly you wont have an issue but you will find the exception. They also say dont use a pressure washer, we use it all the time with no issues. Pressure washers are more for speed and some applications are difficult.
Regular Guest
You don't fire high pressure steam at two inches away, it's merely a way of supplying warmed water at the end of a 300' line. Works best on organic matter like dandelion. Have never had coil leak issues, but have knocked 100lbs off head pressures. The coils we're cleaning are large and some have been cleaned a dozen times over fifteen years with no problems. When I first took over one contract it was their spring ritual to supply all their units with garden sprinklers (2000' of hose).
Banned
http://books.google.com/books?id=tH6...page&q&f=false. Sometimes we need to go back to the basic
Professional Member
I have working in the field for 2 1/2 years. Like many people have said there should be no reason to clean an evap coil as long as filters are getting changed regularly, but we have 3 building (12 large RTU's) that are from 98 that we will be cleaning this year. You must use an evap cleaner not as harsh as cond cleaner. I also would not recommend using a pressure washer or air to clean, you can but a spray mixer at any supply house and hook it to a hose and select the concentraion of cleaner to water you want.
Professional Member
We use a mix of methods to clean coils. Most of the RTU's get just a regular hose with a sprayer end on it. We try not to use coil cleaner unless it's needed. I've been using Simple Green for a coil cleaner (diluted of course), and it seems to work pretty good, not to mention is kind handy to have on the van for misc other mess's I create too.
We do have a power washer that we use too. It mostly gets used on remote sites that don't have water, and it works great on the job sites where the water is a mile away since that line is a lot easier to drag around, not to mention you have pressure at the end of 200' of line vs a trickle at the end of 200' of garden hose.
We also use the power washer on the thick coils, there's just no way you can blow through 4, 6 or more inches of coil with regular water pressure. Just takes some common sense when you're doing it.
I don't think there's really a right and wrong way to clean coils (ok, well there's plenty of wrong ways, like smashing coils flat etc, but you know what I mean), it's all subject to personal opinion and technique.
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AOP Committee/Professional Member*
I think you will find that this is not the case, as time goes by and you build more experience. You see, the filters will NOT catch 100% of what is in the air. During economizer operation you suck in whatever is flying around out there, including clouds of fine dust that is upwind of the unit during mall builds and expansions. This stuff DOES find its way through the filters, as well as many other fine particulates, and it builds up on the evap.
One really bad set of evaps belonged to a place that baked fresh bagels every morning. The units had only seen filter changes and on-demand repairs. The evaps were 90% blocked with a mixture of oil and flour. It took most of the day with blue alkali coil cleaner and a shop vac to get the coils clean.
If you will be there to use no-rinse green cleaner on a regular basis, then I agree it is theoretically possible to avoid using a stronger cleaner. BUT, and it's a BIG but, commercial is a merry go round of companies and service brokers. For example, I am going to an office supply store tomorrow that I used to service two years ago for a different service provider. So, it has come full circle.
The key is to use the method that is EFFECTIVE, and that method will vary from site to site, and unit to unit.
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2 Tim 3:16-17
RSES CMS, HVAC Electrical Specialist
Member, IAEI
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Professional Member
I see here that everyone is going back and forth about steam and pressure washing... I'm still in school so I may be wrong... I do agree that using steam will cause the pressure to increase and go off the chart IF and that's on IF the system is still connected if you take the coil off of the system to clean it which most people do there won't be any refridgerant in it and the system would be open so the pressure wouldn't increase. As for the pressure washer wouldn't it mess up the fins even with a water hose sprayer if you don't sprap the water straight to the fins it will mess them up... Like I said I'm still in school and have 5 months left but its my thoughts and the way I see it and I could be wrong...
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LOL y7Turbo who was that relpy for?
Banned
Now you guys want to kill a poor cat just because you don't know how to clean
A coil ,very sad
AOP Committee/Professional Member*
Removing the evap for cleaning is done more often in residential service.
In commercial, you "clean in place."
Using a pressure washer takes a little instruction and a little practice, and it is easier to get the pressure washer up on a roof than a steam jenny.
Frankly, it's already hot enough on a roof when I have to clean coils, so I'll pass on the steam.
As for the cat, as long as it is "effective," you can do it any way you like.
[Avatar photo from a Florida training accident. Everyone walked away.]
2 Tim 3:16-17
RSES CMS, HVAC Electrical Specialist
Member, IAEI
AOP Forum Rules:
Professional Member
Ok we haven't covered too much in commercial right now its mainly been residential with a little commercial so i didn't know you would "clean in place" I still think the steam would increase the pressure in the coil...and everything takes practice but I'm still thinking that the pressure if not directed at the coil properly will bend and smash the fins...but like mentioned as long as its effective you can do it anyway you likeRemoving the evap for cleaning is done more often in residential service.
In commercial, you "clean in place."
Using a pressure washer takes a little instruction and a little practice, and it is easier to get the pressure washer up on a roof than a steam jenny.
Frankly, it's already hot enough on a roof when I have to clean coils, so I'll pass on the steam.
As for the cat, as long as it is "effective," you can do it any way you like.
Professional Member
Just bringing a funny post into this thread man, its not directed to one person.
All of us have a different way to do things, if you ask 10 guys a question you'll get multiple answers.. I may not agree with some of them, but if they are cleaning the coils good without damaging the fins then who are we to say someone is wrong?
Professional Member
The reasons we use pressure washers are because most of the buildings we service dont have water near by. At the end of 200,300 or 500 ft of hose, there is no pressure, so a pressure washer does the trick.. Its also great for the thicker coils, some units have coils that are more than 4" thick with a high fin per inch count . I find it hard to believe you're getting through that coil without a pressure washer. If some of you are, you must have pretty damn good water pressure, cause we sure dont at most places..
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