Posted: August 13, 2026
Summer in the Montgomery County, PA, area brings plenty of sunshine and some seriously warm days.
If you rely on propane to power your home, you may wonder what all that heat does to the fuel sitting in your tank. The short answer is, quite a bit. The good news is that with the right setup and a few precautions, your propane system can handle the heat without issue.
Propane is a liquefied gas, which means it’s stored as a liquid under pressure and converts to gas when released. Temperature plays a direct role in this process.
When the mercury rises, liquid propane expands. According to the Propane Education & Research Council, propane expands approximately 1.5% in volume for every 10°F increase in temperature. That might not sound like much, but inside a sealed tank, it adds up fast, and it’s exactly why safe storage practices matter.
Most tanks are also equipped with a pressure relief valve. If internal pressure gets too high, this valve releases gas to prevent a dangerous buildup. It’s a critical safety feature that works quietly in the background, but it’s a reminder that heat and propane demand respect.
If you’ve ever noticed that your propane tank is never completely full, that’s intentional, and it’s all about thermal expansion.
Propane suppliers follow a standard practice of filling tanks to no more than 80% of their total capacity. That remaining 20% acts as an expansion buffer, giving the liquid propane room to expand safely as temperatures climb. Without that space, pressure inside the tank could rise to dangerous levels on a hot summer afternoon.
This is true regardless of tank size. Whether you have a 120-gallon tank or a 1,000-gallon tank, the 80% rule applies.
Here’s something many homeowners don’t consider: the color of your propane tank matters.
Dark-colored surfaces absorb significantly more heat than light-colored ones. A dark green or black tank sitting in direct sunlight on a 90°F day can reach much higher surface temperatures than a white or silver tank in the same conditions. More surface heat means more internal pressure.
That’s why most above-ground propane tanks are painted white, silver, or another light-reflective color. It’s not aesthetics, but a safety measure that reduces the amount of solar heat absorbed by the tank. If your tank is above ground and exposed to direct sunlight, a light-colored finish is essential.
Underground tanks, by contrast, are naturally insulated by the surrounding soil, which keeps temperatures more stable year-round.
A few simple steps can go a long way toward keeping your propane system running safely through the warmer months:
Keeping your propane system safe and efficient starts with the right setup, and that’s where County Propane comes in.
We offer affordable propane tank leasing for homeowners across Montgomery County, PA, and surrounding communities. With a leased tank, you don’t have to worry about upfront purchase costs, installation expenses, or long-term maintenance bills. We handle everything: professional installation, ongoing maintenance, and any repairs that come up.
Prefer a permanent installation? We also offer expert installation of both above-ground and underground tanks in sizes ranging from 120 to 1,000 gallons. Every installation meets local codes and safety standards.
To learn more about our heating oil or propane services, or to schedule a delivery, get in touch with County Propane today. Our team is ready to answer your questions, provide personalized recommendations, and ensure your home stays comfortable and energy-efficient all year long.