How to Switch Between Oil Based & Water Based Coatings in Airless Sprayers & Paint Equipment
We often are asked if you can and if so how you switch between oil based and water based coatings with paint equipment, whether it be an airless sprayer, a paint pressure pot, or something else entirely. The short answer is yes you can switch between oil and water based coatings and paints even within a single job, the key is to understand how to do so properly. Failure to properly switch between oil and water based coatings can result in your pump being filled with chunks that can be a pain to get removed from the pump and line. By following the steps outlined below you can be sure your airless sprayer will function smoothly after switching from oil to water based coatings on the job.
Step 1 for switching between oil and water based coatings - Flush the pump with the water
If your currently using an oil based coating and want to switch over to a water based, you will want to use water to clean just the pump out at first and then the pump and hose. You will first make sure the airless pumps pick up tube is inserted in a container of water and direct the dump valve tube into a clean container. Then you want to make sure the airless pump has the prime/ spray control turned to prime. This will flush the pump fluid section with water. Run the pump until your confident all oil based material has been forced through the pump leaving only water behind.
Step 2 for switching between oil based and water based coating - flush the airless hose and spray gun with water
After cleaning the pump section, you should then switch the prime/ spray valve to spray and spray the until you see water coming from the airless spray gun, this will confirm you have cleaned the line of all oil based mateiral. After this is complete you can then put the pick up tube from your airless sprayer into the water based coating and set the spray/ prime valve to prime until the new water based coating has primed your fluid section. Then you can set the spray / prime switch to spray and hold the trigger until the new material begins spraying from your airless paint sprayer.
Switching from Water Based to Oil Based
If your switching from water based products to oil based the same steps will apply but you will be using the appropriate solvent for your oil based material to flush the pump. You will first flush the pump using the prime/ spray valve by turning it to prime with the airless sprayer pick up tube in the solvent and the dump valve tube in a clean bucket. Next you will turn the spray/ prime valve to spray and begin to watch for a brief break in your spray pattern which will typically indicate the airless hose and airless spray gun have been completely cleaned of any water based product. After you have flushed the airless sprayers fluid section and the hose with the compatible solvent of your new material, you can then insert the pick up tube into the new oil based material and prime the fluid section by putting the dump tube into a bucket with oil based material or a clean bucket and waiting till the new material comes through the dump tube. After the fluid section is primed you can switch the spray/ prime switch to spray and spray until the new oil based material is sprayed from your airless spray gun.