What is the minimum tubing specification for steam condensate return lines?

The minimum tubing specification for steam condensate return lines is Type K copper tubing. This specification is correct because Type K copper has the thickest wall of all the copper tubing types, which makes it particularly suitable for high-pressure applications such as steam. The thickness provides additional durability and strength, which is essential in steam systems where temperatures and pressures can fluctuate significantly.

Type K copper is also highly resistant to corrosion, which is vital in steam condensate return lines where moisture and potentially corrosive substances are present. The use of Type K tubing ensures a long-lasting and reliable system, minimizing the risk of leaks or failures in the plumbing.

Other types of tubing, such as Type M or Type L copper, have thinner walls and are generally used for less demanding applications, making them unsuitable for steam condensate lines. PVC tubing is also not appropriate for this purpose due to its inability to withstand high temperatures and pressures associated with steam systems.