Since the top operating expenses in many car washes, besides labor, are chemical and water costs, it is imperative to ensure that the fluid handling system is in optimal shape. If using a direct-inject, boosted pressure system, these 10 maintenance tips will help ensure that the system is operating efficiently and providing customers with the consistency, wash quality, and “show” that they deserve.
1. Optimize the System, Match Injectors to Nozzles
It is important to optimize the system in order to have the most efficient chemical delivery, use the least amount of chemistry and water, while still getting great show and vehicle coverage. One way to optimize the system is to match the injectors to the nozzles. Injectors increase or decrease the amount of water in the solution line, while nozzles determine the pattern and back pressure of the solution. Selecting too large of an injector can cause issues with chemical draw (vacuum) and wastes water. Selecting too small of an injector results in a poor show in the wash and poor vehicle coverage. To optimize, match the total nozzle flow rate to the injector. This will result in proper water and chemical usage and stunning visual results.
2. Check and Clean the Wye Strainer(s)
![]() |
Match injectors to nozzles. |
If the system has a booster pump, the easiest preventative maintenance to perform is checking and cleaning the wye strainer(s). The life of the pump is significantly dependent upon the state of the pump’s wye strainer. This small, but important, piece can — if clogged — decrease the overall longevity of the pump. Wye strainer screens should be cleaned on a monthly basis to increase life and optimize pump performance. Because clogs can be due to particles from the pump impellers resulting from pump wear or overheating issues, cleaning the wye strainer monthly will also give you valuable insight into the health of the pump. Many times, problems occurring within the pump will be visible before they become catastrophic and the pump completely fails.
3. Check, Replace, or Install a Water Filter
![]() |
Wey strainer. |
Water filters, if installed, enhance the life of the pumps and valves by reducing particulates including sand, scale, and rust. Water filters should be checked on a monthly basis, and replaced as needed.
4. Inspect/Replace Chemical and Solution Lines
Chemical lines ought to be inspected on a semi-annual basis, and replaced as needed. Buildup of chemical residue or a kink in the lines can create an unwanted restriction and wreak havoc on the system that will leave your head spinning. Closely inspect all lines and connection points for leaks that can lead to waste of chemistry and/or water.
5. Proper Line Sizing
Line sizing is important because it plays a role in backpressure and the amount of water and chemical being delivered to the arch. If the line size is too small, or if the run length is too long, no chemical will be drawn, resulting in poor delivery in the wash. Too large of a line is not typically a concern. For proper line sizing, refer to the below charts.
6. Clean/Replace Media in Foam Generators
Foam generator media can also cause unwanted backpressure in the system and poor performance in the wash. It’s important to inspect and clean media at least four times a year. Many chemicals, when mixed with air, begin to coagulate. This sludge can build up and eventually completely clog the foam generator.
7. Clean/Replace Nozzles
Nozzles are a very important part of a successful wash. If nozzles are clogged or restricted, they will create unwanted backpressure and poor delivery of chemistry to the car. This will leave you with unhappy customers and inconsistent results. Nozzles can often be cleaned by removing them and running them under hot water. Using a pipe cleaner to clean the nozzles works as well. The International Carwash Association’s WaterSavers® program requires that all spray nozzles must be inspected annually to ensure maximum efficiency of water used.
Vacuum test each injector at the hose barb.8. Check/Replace Metering Tips
Metering tips are used to control the amount of chemical that is mixed with the water and the strength of the chemical solution. Metering tips should be checked on a semi-annual basis, and replaced when needed. Metering tips can become clogged due to coagulated chemical or sediment from chemical draw. It’s also important to note that some chemicals start to crystallize and harden when mixed with water, which can lead to clogged metering tips. If you encounter this problem, the metering tip should be moved downstream in the chemical line with a remote metering check hub.
9. Check/Replace Injectors
Periodic inspection of injectors ensures that they are delivering a consistent amount of chemical and water to each and every car. Vacuum test each injector at the hose barb to make sure that every one is pulling a minimum of 20 in/hg. If not pulling this amount, it’s an indication you have a problem in the system. It may or may not be the injector, but this is a very easy way to test the system health of each function.
Over time, standard metal injectors may be susceptible to failure due to the use of corrosive and acidic chemicals. Replacing injectors for new, all-composite injectors that stand up to the most aggressive, yet common car wash chemicals will extend the life of your equipment.
10. Inspect Check Valves
![]() |
Composite injector. |
Check valves prevent the backward flow of fluid and are susceptible to sticking open and collecting coagulated chemistry. Inspect check valves for sticking and buildup of chemistry inside that may cause unwanted restrictions and back pressure.
The “up time” of car washes and the health of car wash equipment play a key role in not only acquiring and keeping customers, but also minimizing expenses. Strong performing equipment can increase car counts, enhance results, and — ultimately — increase profits. Performing these 10 maintenance tips on your direct-inject, boosted pressure system on a regular basis will ensure optimal performance of your equipment and enhance customer show.
Inspect check valves for sticking and buildup of chemistry.
Chris Strom is distributor services manager for Eagan, MN-based Hydra-Flex Inc. You can visit the company on the web at www.hydraflexinc.com.