09/29/2026
TECH TIP: COLD WEATHER IS COMING
Temperatures are starting to drop, and now is a good time to make sure your spray rig is ready for colder weather.
One of the biggest things to pay attention to this time of year is Delta T. As ambient temperatures drop, the difference between your desired material temperature and the temperature outside becomes greater. That means your equipment has to work harder to get the material up to temperature and keep it there.
Your temperature setpoint and your actual material temperature aren’t always the same thing.
This is also a good time to check your heated hose. Make sure it’s heating properly from the proportioner all the way to the gun. Problems that may have gone unnoticed during the summer can become much more obvious once the hose is fighting colder ambient temperatures.
A few other things to keep in mind as it gets colder:
• Keep your chemical warm. Starting with cold drums puts more demand on your primary heaters before the material ever reaches the hose.
• Keep the rig conditioned. Maintaining a reasonable temperature inside the rig helps your entire system do its job.
• Give the system time to warm up. Getting a temperature reading at the machine doesn’t necessarily mean the entire system has stabilized.
• Pay attention to substrate temperature. Your equipment can be running perfectly and your material can be at temperature, but a cold substrate can still cause problems. Always follow the chemical manufacturer’s recommended application temperatures.
• Don’t forget about heat loss. The colder it gets outside, the harder your heated hose has to work to maintain material temperature all the way to the gun.
Cold-weather spraying is all about temperature management. Your proportioner, heated hose, chemical, rig, and substrate all play a part.
Take a little time now to make sure everything is heating the way it should before colder weather gets here.
Stay warm and keep spraying.
— Urethane Supply
