These Frequently Asked Questions are designed to provide a better understanding of our products and their technical applications of the HVACR industry. If you are unable to find your question below please call us at 800-554-5499 or email firstname.lastname@example.org.
When acid cleaning a cooling tower or evaporative condenser, how do I know when the system is clean?
Both Liquid Scale Dissolver and Imperial Scale Remover (Season Start) contain a "pH color indicator" that will guide you through the process. When the acid/water cleaning solution is at proper strength, it will be green-to-light blue in color. When it is neutralized and unable to dissolve scale, it will be purple. When it turns purple, another dose of acid equal to the first must be added. The system is usually clean when you can maintain the green color for 20-30 minutes.
When an acid cleaning is complete, what can I do with the acid solution in the tower?
You should always be aware of any local regulations that may govern the disposal of acid cleaning solutions. However, in nearly all localities, it is acceptable to flush the solution to a sanitary sewer with water once the solution has been neutralized. The solution should be neutralized while it is still in the system, through the use of soda ash or similar alkaline neutralizer.
Which of your acid descalers can be used to clean a cooling tower that has galvanized surfaces?
Either Liquid Scale Dissolver (a liquid hydrochloric or muriatic acid) or Imperial Scale Remover (a powdered sulfamic also known as Season Start) can be used. However, all acids will remove a small amount of galvanizing during cleaning, and the use of Imperial Scale Remover, or Season Start, is the best choice as its inhibitors will provide up to 96% protection of the galvanizing.
Do you have a product to equal or replace Simple Green?
Yes, our Green Clean will easily fill that need; in fact, it has been found to be a better cleaner than Simple Clean.
How can I improve the cleaning process in order to make the coils stay cleaner longer? How can I protect the coils?
Use of the Teflon-based coil protectant, Cal-Shield, will help the coil to repel moisture as well as dirt, grease and grime. It will help the coil to stay cleaner longer, and the next cleaning will be very easy. Cal-Shield also provides protection for coils operating in aggressive or acid environments such as walk-in food coolers and salt air environments.
How to Clean Air-Cooled Equipment and Filters
Reduce service calls and increase the efficiency of air-cooled condensers, permanent air filters, evaporator coils, window units and other finned cooling/heating coils or equipment. Select one of Nu-Calgon Wholesaler, Inc. cleaners. They are based on nearly 40 years of experience and technical background in coil cleaning.
Greasy dirt and dust in the air collect on air conditioner and refrigeration heat exchange units. If finned heating or cooling coils are left uncleaned, heat transfer is reduced, compressors have to work much harder, operating costs go up and valuable equipment often breaks down when it is needed most. For example, for every 2°F rise in condensing temperature caused by dirty coils, the system efficiency drops by 1% and power consumption rises by 1%. A staggering price to pay for dirty coils.
In addition, clogged and dirty permanent filters restrict air flow and do not filter air, allowing dirt to contaminate rooms and stain walls around air ducts.
Regular cleaning with Nu-Calgon products protects equipment and helps maintain peak operating efficiency and low operating costs.
A Look At The Equipment
When air-cooled condensers are designed and manufactured, each units has a specific heat transfer capacity. These capacities are based upon clean surfaces. As dirt and dust accumulate, heat transfer is reduced, resulting in a higher head pressure which in turn brings about increased power requirements and loss of efficiency; remember, for every 2°F rise in condensing temperature, efficiency drops 1% and power consumption increases 1%. Consequently the unit must be cleaned to restore the lost capacity.
Buildup of greasy dirt on air conditioning or refrigeration cooling coils makes the units work much harder. Impeded air flow and poor heat transfer can put a sever strain on both the equipment and the pocketbook. Cleaning removes dirt and greasy film from evaporator coils and enables the equipment to operate more efficiently. Cooled air is cleaner, too.
Permanent air filters:
When permanent air filters become clogged with dirt and soot, air flow is restricted. Cleaning restores designed air flow and it provides for cleaner air.
Both the condenser and the evaporator can become dirty. Dirty window units can be cleaned easily without damage to paint. Note: Wrap fan motor with plastic sheet before spraying with cleaning solution.
Electronic Air Cleaners:
These filters have charged plats that electronically remove pollutants, tobacco, tar, etc. from the air. Specially-formulated cleaners are necessary to clean them.
General cleaning jobs:
Several of the Nu-Calgon products can be used effectively in many general cleaning situations where there is a buildup of grease or other heavy soil. These include cleaning greasy painted or enameled equipment or walls, woodwork and floors, and practically any metal, cement, glass, tile or linoleum surfaces. Use CalClean, Green Clean or Tri Pow'r at a concentration of 1 to 2 ounces per gallon of warm water.
A Look At The Products
Air Cooled Evaporator Coils Other Finned Coils Electronic Air Filters Window Units General Cleaning Bio-Degradable USDA Accepted CalClean X X X X X X X Special HD X X X X X X Alka-Brite X X X Nu-Brite X X X Foam-Brite X X Cal-Brite X X X X Evap-Pow'r X X X Tri Pow'r X X X X X Green Clean X X X X X
Discussion Points on Cleaning
The primary goal in cleaning air-cooled condensers is to emulsify the greasy dirt and grime so that it can be flushed away by rinsing. This restores designed heat transfer and air flow. A good alkaline cleaner like CalClean is the choice, and the selection of Special HD CalClean would be recommended if the soil or grime is particularly stubborn.
If foam during cleaning and brightened aluminum fins after cleaning are desired, select any one of the Nu-Calgon "Brite" products (Alka-Brite, Nu-Brite, Foam-Brite). They will provide the cleaning of the CalClean products with the added features of foam and brightening. And, when more accelerated foaming and brightening are desired, particularly where hydrofluoric acid-based products were used, select Nu-Brite or Foam-Brite. They are formulated to out-foam, out-brighten and out-clean the HF-based products.
If economic considerations and ultimate safety are the primary factors in selecting a cleaner, select Tri Pow'r. It will provide excellent cleaning and detergency, and it will degrease at a fraction of the cost of other market available coil cleaners.
Typically, the desired goal is the same as in cleaning air-cooled condensers . . . . removal of greasy dirt and grime and restoration designed capacities. If an acid-based product is desired, where some brightening and foaming is achieved, use Cal-Brite followed by a thorough rinsing. Or, a good alkaline cleaner like CalClean (10:1) or Tri Pow'r (5:1) can be used followed by a complete rinsing. If rinsing is not possible or if it is not desirable, a product that combines "metal safeness" without rinsing is suggested . . . . so long as suitable humidity-condensation is anticipated. Evap Pow'r-C mixed at 3 parts water to 1 part product can be used, or its ready-to-use version, Evap Pow'r-RTU, may be selected.
Electronic Air Filters:
When electronic air filters become coated with tobacco tars, gummy dust particles and other stubborn deposits, they are difficult to clean. More importantly, they lose their ability to adequately remove these types of objectionable items from the air. Typically, wherever electronic air filters are installed, the quality of the air is paramount.
Most alkaline cleaners don't because they simply cannot emulsify the stubborn deposits such as tobacco tars. Special HD CalClean was specifically formulated to handle such a cleaning requirement. It contains an extra-strong blend of surface-active agents and alkaline cleaners designed especially for cleaning electronic air filters, Special HD CalClean outperforms ordinary detergents and is safe to use. It will not corrode or tarnish aluminum or other metals when used in recommended concentrations.
General Cleaning Jobs:
Most of the Nu-Calgon products can be used effectively in many instances where there is a build-up of grease or other heavy soils. Green Clean, Tri Pow'r or even CalClean would be good choices here.
Once coils are clean, they should be sprayed with a fine coating of Cal-Shield, a Teflon-based product, as it can protect the coil, helping it to stay cleaner longer and to clean-up much easier when cleaned.
I’m cleaning an air-cooled condenser and I want the best foaming and cleaning product you have. What is it?
So long as the condenser coil is located outside or outdoors, use either Foam-Brite or Nu-Brite.
Regardless of foaming characteristics or formulation types, what is the very best cleaner you have?
That would be Special HD CalClean. It is an excellent degreaser and cleaner, and it contains the best surfactants or wetting agents and the best corrosion inhibitors to protect system metal. Also, it can be used to clean electronic air cleaners as it is effective versus nicotine tars. It can be diluted 20:1 or even 40:1 and used for a wide variety of coil cleaning and general cleaning.
What can I use to clean an evaporator coil in a "no-rinse" application?
You may use Evap Pow’r or Evap Foam - No Rinse. The first, Evap Pow’r, is available in two forms: a concentrate, Evap Pow’r-C, that should be diluted 3:1 and a ready-to-use product, Evap Pow’r - Rtu. Evap Foam - No Rinse, is an aerosol product that delivers a fast-breaking foam to the coil surface for excellent "no-rinse" cleaning.
What considerations should I have when cleaning condensers located on rubber roofs? Which of your products are safe on rubber roofs?
The most common types of rubber roofs are Modified Bitumen, both Coated and Uncoated, and EPDM-Type roofing. And the only one of the three that would be a concern is the Coated Modified Bitumen as it contains fibrated aluminum. Therefore, those cleaners that foam and brighten the aluminum fins or those that are quite strong in concentration should not be used on this specific type of roofing material. Instead, cleaners like regular CalClean or Tri-Pow'r should be used...
What cuts through grease or animal fat deposits on coils better, acid-based cleaners or alkaline-based cleaners?
Alkaline-based cleaners are always better degreasers and cleaners.
Which of your coil cleaners are biodegradable?
All Nu-Calgon coil cleaners are biodegradable.
IAQ Assurance Program
What is the IAQ Assurance Program?
This is a three step program that will enable an air conditioning, refrigeration ventilating system to operate at designed conditions in terms of air quality. It involves....
Cleaning: Through the use of Evap Pow'r or Tri Pow'r, evaporator coils condensate pans and surrounding surfaces are cleaned to remove existing soils and dirt build-up Disinfecting: Through the use of Bio-Fresh cd, the coil, pan and surrounding surfaces are disinfected. Bio-Fresh cd is a disinfectant, virucide, fungicide, mildewstat and deodorant. And, it has been tested to be effective verus Legionella.
Protecting: The final step in this IAQ program is the use of Pan-Pads, a condensate pan treatment that is effective against a wide spectrum of bacteria, including Legionella. It keeps condensate pans clean, preventing bacterial growth and thereby preventing blocking of the pan's drain.
Ice Machine Treatment
Do You Have These Ice Machine Problems?
Lime Scale Formation,Sediment, Objectionable Taste or Odor, Slime Growths,Rough Freezing Surface Cloudy or Milky Ice, or Dirty Cooling Coils< /p>
Lime Scale Formation:
Lime scale is a common problem in ice machines. Even though the water is not heated, the hardness minerals tend to concentrate in the water and precipitate out on the freezing surfaces. The ice tends to stick to the scale and this jams the machine. Years of experience with ice making equipment have proven that the best way to solve the problem and reduce service calls is to prevent this scale formation by treating the water with the food-grade polyphosphate, Micromet. Before the treatment is started, however the machine should be cleaned, and possibly sanitized.
Removing Scale Deposits:
Liquid Ice Machine Cleaner
Nickel-Safe Ice Machine Cleaner
Controlling Slime Growths:
Preventing Scale Deposits:
Micromet is a slowly soluble food-grade polyphosphate that keeps scale-forming minerals in solution and prevents formation of scale on the freezing surface of ice machines. There are two types of Micromet that may be used: Micromet Crystals which dissolve at the rate of about 25% per month and require monthly recharging, or 6R Micromet which dissolves about 3-5% per month and lasts up to 6 months between service calls. It is NSF-listed and it is USDA-accepted.
Prevent Scale, Removes Sediment and Removes Objectionable Tastes and Odors:
The complete treatment program for commercial ice makers, coffee urns and brewers, beverage makers and other water-using equipment such as humidifiers, steamers and residential refrigerator ice makers.
Micro-Plus Treatment Systems are available in a variety of size capacities, from the Micro-Plus 2, which can be used on equipment using up to 12 1/2 gallons of water or 25 lbs. of ice per day, to the Micro-Plus 16 for treating up to 100 gallons of water or 1000 lbs. of ice per day. Micro-Plus systems are designed and manufactured to eliminate or control the three primary water-related problems...lime scale, silt and sediment (down to 20 microns), and objectionable tastes and odors. When properly sized, Micro-Plus will last for six months.
All units are constructed of NSF approved polypropylene, and are tapped on each end with 1/4" FPT. Installer may then utilize flare fittings, compression fitting or the male plug for quick disconnect fittings.
Prevent Lime Scale, Sediment or Objectionable Tastes and Odor:
The NP Series is a complete, multi-functional treatment system, consisting of two different size housings, the NP24DD and the NP48DD, and a family of "problem solving" cartridges.
The NP Series has been developed in order to permit the service technician or user to customize their installation to address a specific water-related problem or problems. There are cartridges for the control of scale, for the removal of silt and sediment and for the removal of objectionable tastes and odors And, the cartridges are available in sizes to fit both NP Housings.
The product line is also augmented by accessory items. Two different bracket assemblies are available to permit the installation in series of two or three NP Housings. By using the bracket assemblies, the installation can be customized to correct two or three water-related problems. Also, a gauge package is available for use where it is necessary to continually monitor the pressure of the water serving the ice machine, beverage machine, etc. This is often a recommended procedure when filtering water with a high level of silt or sediment.
Select the Appropriate Cartridge to Solve Your Particular Problem:
The NP246R Micromet Cartridge contains sufficient 6R Micromet to provide scale control on ice machines making up to 900 lbs. of ice per day or other equipment using up to 100 gallons of water per day. The NP486R Micromet Cartridge contains double the amount of 6R Micromet and can treat up to 1800 lbs. of ice or 200 gallons of water per day. When properly sized, treatment will last for six months.
NP246R Micromet Cartridge - 4705-87
NP486R Micromet Cartridge - 4715-87
Use either the NP24S or the NP48S polypropylene sediment cartridges. Both are rated at 20 microns, and provide long service life. Exceptional dirt-retaining capability. Low pressure drop ratings...0.5 psi at 5.0 gpm flow. Manufactured from FDA-Approved materials.
NP24S Cartridge - 4702-87
NP48S Cartridge - 4712-87
Scale Control & Taste/Odor Removal Cartridges:
Both of these NP Series Cartridges are highly-specialized elements, bringing the capabilities of 6R Micromet and activated carbon together in one element. Designed for use in either the NP24DD or the NP48DD Housings, they provide for the control of scale as well as the removal of objectionable tastes and odors and filtration to 10 microns. The NP24PC can handle up to 65 gallons of water (600 lbs. of ice) per day, while the NP48PC can handle 135 gallons (1200 lbs.) per day.
NP24PC Micromet/Carbon Cartridge - 4706-87
NP48PC Micromet/Carbon Cartridge - 4716-87
Objectionable Tastes and Odors:
Use either the NP24C or the NP48C carbon block cartridges. Both are rated at 10 microns and provide greater absorption capacity than typical granulated activated carbon. Removes VOC's, TOC's and cysts (giardia lamblia). Manufactured from FDA-Approved materials.
NP24C Cartridge - 4701-87
NP48C Cartridge - 4711-87
Rough Freezing Surface
Food Grade Silicone:
Often times, particularly in older machines, the freezing surface will not be as smooth as it was at the time of original installation. Use of Food Grade Silicone will provide a non-stick surface and help prevent binding and sticking of the ice.
15 3/4 oz. aerosol - 4084-03
Dirty Cooling Coils
Buildup of greasy dirt on refrigeration cooling coils and on air-cooled condensers impedes air flow and reduces heat transfer. This condition can put a severe strain on both the equipment and the pocketbook. Protect equipment and maintain efficiency by using CalClean to remove dirt and greasy film from coils and filters.
20 oz. aerosol - 4081-75
A "no-rinse required" condenser coil cleaner in a convenient aerosol package. Double action of high pressure blast and solvent cleaning restores design efficiency of condenser coils...quickly and easily. It has a pleasant odor and is non-flammable and non-conductive.
18 oz. aerosol - 4290-75
Nu-Cal UV Series:
After years of testing and refinement, an ultraviolet light method of purifying water and eliminating slime growths in ice machines is now available. Disinfection is achieved by exposing the makeup water to ultra-violet light at a controlled water flow rate and then filtering with carbon. The UV Series is disposable, affordable and will last for twelve months. There are two units available: NP-UV4 which will handle a maximum flow of 0.5 gpm and the NP-UV6 which will handle 1.0 gpm. Both are equipped with 1/8" FPT connections. The power supply is regulated by a custom designed 110V ballast.
NPUV4 - 4720-04
NPUV6 - 4720-06
110V Ballast - 4720-99
How do I prevent scale formation in ice makers?
Two things must be done. First, a bleed or dump cycle of the unfrozen recirculating water must be maintained. Second, the make up water needs to be treated with a food-grade polyphosphate like 6R Micromet. Treatment with the phosphate will stabilize the minerals and thereby avoid scale formation.
How do I treat the make-up water with a polyphosphate like 6R Micromet to prevent scale?
The polyphosphate may be introduced by passing the make up water through one of two general types of treatment: in-line filtration devices like Micro-Plus or cartridge/housing filtration devices like the NP Series.
We have a slime-growth problem in our ice makers. How can that be corrected?
The source of the problem is bacteria, and it may be water-born or air-born. One approach would be to sanitize the machine on a regular basis with IMS-III Ice machine Sanitizer after cleaning. This will delay the onset of the slime growth and increase the time between service.
What is the difference between Liquid Ice Machine Cleaner and Nickel-Safe Ice Machine Cleaner?
Both are food-grade acids formulated to remove scale deposits from ice makers. However, when cleaning a machine with nickel-plated evaporators, only the Nickel-Safe product should be used.
Refrigeration Oils/ Lubricants
It is said that POE’s are very hygroscopic, that they easily absorb or assimilate moisture. Does this mean that once I open a container of a POE and use some of the contents, I must throw out whatever remains, that the exposure to the ambient air has allo
Quite the contrary. So long as the container of POE is tightly capped after each use, the oil can be used until the container is exhausted.
It is said that there are refrigerants available for replacing CFC’s, use of which allows for no oil change . . . that I can stay with mineral oil. Is that okay?
All of the refrigerants that are recommended as "CFC replacements with no oil change" are blends that incorporate a significant level of R-22 as part of the gas. And because R-22 has marginal miscibility with mineral oil, use of the "no oil change" approach will jeopardize system performance, particularly in low temperature application. Change the oil to an alkylbenzene like Zerol. Use of mineral oil with these refrigerants encourages problems like carbonization or burning of the mineral oil, loss of capacity, loss of efficiency, etc.
What can I use to check the acid level of a refrigeration oil system?
Answer: The best service tool is a refrigeration oil acid test kit, and the best acid test kit technology is one that incorporates a "phase separator" in the test procedure like our Phase III Test Kit. The phase separator separates the oil being tested from its acid content, and that permits easy, accurate determination. In fact, the Phase III Test Kit can be used on all three oils: mineral oils, alkylbenzene oils, and polyol ester oils (both ICI and Mobil).
What does "miscibility" mean when used in context of oil and refrigerant performance?
Miscibility is the ability of two substances to mix together. When using the term in discussing refrigerants and oils, it refers to the ability of the gas and the oil to remain as one mixture, one homogeneous mixture, as they travel through the system, from the compressor and back to the compressor. Proper heat transfer and efficient system operation require an oil and a gas that exhibit good miscibility, particularly in the evaporator where temperatures are lower. Polyol esters (POE’s) have good miscibility with all refrigerants while alkylbenzenes like Zerol have good miscibility with both CFC’s and HCFC’s: (especially HCFC’s because of their R-22 content). Mineral oils exhibit the best miscibility with R-12, and only marginal miscibility with R-502 and HCFC’s.
What is the best oil selection I can make if I’m using R-22 in a system?
Without question, you should use an alkylbenzene lubricant like Zerol, and for one very good reason: Zerol alkylbenzene has the best miscibility with R-22, significantly better than mineral oil, and it’s use with R-22 will insure good oil return to the compressor and no oil logging in the evaporator.
When retrofitting a CFC system to an HFC, why must the mineral oil be reduced to a concentration below 3-5%?
Because of the mineral oil’s poor miscibility with the targeted HFC. Use of HFC’s requires the use of a POE oil and optimum system performance will only be achieved when the mineral oil content is below 3-5%.
Why must I use a POE oil with the newer HFC refrigerants like R-404A, R-507, etc?
Because the HFC’s have very poor miscibility with mineral oil and only marginal miscibility with alkylbenzenes. HFC’s exhibit excellent miscibility with POE’s.
How to Remove Scale From Cooling Tower Systems?
Scale is the solid matter left after water is heated or evaporated. It forms thick deposits on heat transfer surfaces and prevents the heat from being carried off.
Scale deposits reduce water flow, cut heat transfer and cause high head pressure. The compressor works harder and draws extra current, increasing power costs and causing equipment to fail to product the designed capacity.
The life of the equipment itself is reduced. In fact, excessively high head pressure is a common cause of motor burnout which costs considerable inconvenience and money.
Breakdowns occur during the hottest weather when full capacity is needed.
Customers are annoyed and dissatisfied.
When they can't actually see the scale, on the condenser surfaces, inside the piping and water regulated valves, there's a strong possibility it's there if the head pressure is high (more than 10 pounds above normal), or if the liquid refrigerant line is extra warm. But keep in mind that high head pressure can be caused by mechanical problems, too. These should be checked out before the full blame is placed on scale. Here are just a few of these other causes: pump sucking air, water lines too small, louvers or sprays plugged, tower overloaded, fan trouble, or moist air returning.
How to Test the Scale - If there is any question as to whether the scale remover will dissolve the scale, you can check this by putting a sample of scale into a half glass of water with two or three teaspoonful of the acid. Then stir. If the scale bubbles and breaks up or completely dissolves, go to it! If it doesn't bubble, a sample of the scale can be sent to Nu-Calgon for analysis. We will determine whether it contains sulfate, iron oxide, silica, etc. and advise what can be done to remove it.
Nu-Calgon Scale Remover - "Imperial Grade" - The best and safest dry acid cleaner. Scale remover is a powdered sulfamic acid formulation that contains the best inhibitors available for protecting all metals including galvanizing. A built-in pH color indicator shows how much to use, when to add more and helps tell when the system is clean. A wetting agent and anti-foaming agent are included to help it do a better cleaning job.
Liquid Scale Dissolver - A hydrochloric (muriatic) acid with a low-foaming corrosion inhibitors and a built-in pH color indicator. pH test paper also included.
Liquid Acid Versus Powdered Acid - Some acid users prefer liquid acid for cleaning scaled-up equipment, while some prefer safer dry materials. Both types of materials have certain advantages over each other.
Powdered acids, such as our scale remover, provide the utmost safety in handling to the user. They are nonvolatile and give off no obnoxious or corrosive fumes. Any spillage of the dry acid cleaner is swept up as easily as if it were salt. The dry product is non-irritating to unbroken skin and is easily removed by flushing with water. Since they are less dangerous and easier to use, less supervision is required. Powdered acids are safer for the equipment, and when properly inhibited, will provide excellent protection to steel, copper, brass and aluminum surfaces. Certain formulations like our scale remover are exceptionally safe for galvanizing when no copper corrosion products are present in the system. Powdered acids will not remove old corrosion products as fast as liquid acids, so there is less danger of springing leaks in old corroded systems. Adding too much powdered acid will not cause excessive corrosion rates while adding too much liquid acid can increase the corrosion rate tremendously. Powdered sulfamic acid cleaners are also excellent algaecides.
Liquid acids (such as Nu-Calgon Liquid Scale Dissolver) are somewhat more economical, and strong solutions will dissolve scale and iron oxide deposits faster than powdered acid solution. The liquid goes into solution with no stirring which is a desirable feature, especially in cold weather.
Amount of Acid Required: The amount of acid required to completely clean the system depends upon the amount of scale present. It takes about 2 pounds of powdered acid or 1/3 gallon of liquid acid to react with 1 pound of lime scale. Several doses of acid may be necessary to remove heavy scale deposits. No more than 3 doses of acid should be added to the water together. If scale is heavy, it is better to drain the spent cleaning solution and repeat the cleaning procedure with a fresh charge.
Before cleaning with acid, check the spray nozzles or water distribution holes and clean them out. Drain and flush out the sump. Refill it with fresh water and start the pump again. Shut off the bleed, if there is one. This will cut down on the amount of scale remover you'll need, and prevent waste.
As a starting dosage, add 2 to 3 gallons of liquid acid or 10 pounds of "Imperial" Scale Remover for each 50 gallons of water in the system. If the amount of water in system is not known, the starting dosage can be estimated from the following chart. Even though the acid may have a good anti-foaming ingredient, pour slowly into the system to avoid foaming or pump locking because of the gas released in the cleaning process.
Capacity of System
Tons of Horsepower
Initial Dosage Liquid Acid
Initial Dosage Nu-Calgon
10 2 gals. 10 lbs. 30 5 gals. 30 lbs. 50
10 gals. 50 lbs. 100 15 gals 75 lbs.
The acid solution should be circulated for several hours depending upon the thickness and type of scale. One can usually tell when the equipment is clean by observing the acid solution returning from the condenser. When the returning solution does not contain any bubbles or foam it is a sign that the lime scale has been removed.
The built-in pH color indicator in our "Imperial Grade" Scale Remover and Liquid Scale Dissolver is a very good guide to the proper application of the product. It gives the water a green or light blue color with the acid at the desired strength and causes the water to turn dark blue or purple when the acid is mostly neutralized. This, when the water turns purple, more acid should be added to change the color back to light blue or green. Occasionally, the water indicator does not show up very well in a system where there is a lot of dirt, rust, algae, etc. To double check the cleaning operations and acid strength, pH test paper is provided.
Cleaning Individual Condensers with an Acid Pump:
When cleaning individual condensers or other equipment with the No. 31-TX Acid Pump or other acid circulating pumps, the cleaning solution should contain 1 pound of powdered acid for each gallon of water or 1 gallon of liquid acid for each 5 gallons of water. When using liquid acids never use a solution containing more than 1 gallon of liquid acid for each 5 gallons of water.
The acid solution should be circulated for 1/2 to 3 hours depending upon the thickness and type of scale. The circulating solution should be checked periodically with pH test paper to make sure that it remains at the proper acid strength.
One can usually tell when the equipment is clean by observing the acid solution returning. When the returning solution does not contain any bubbles or foam and is the same color as the solution in the tank, it is a sign the equipment is clean.