CSLB C-36 Plumbing ContractorPlanning and EstimatingMedium
A plumbing contractor is preparing a bid for a commercial office building renovation. The plans specify a new system for condensate drainage from multiple air conditioning units. These units are located in various areas and produce a significant amount of condensate. Which type of piping material is generally considered most suitable and commonly used for condensate drain lines due to its corrosion resistance and ease of installation?
- ACast iron soil pipe
- BCopper pipe (Type L)
- CGalvanized steel pipe
- DPVC (Polyvinyl Chloride) pipe
Show answer & explanationAnswer & explanation
Correct answer: D. PVC (Polyvinyl Chloride) pipe
PVC pipe is widely preferred for condensate drain lines due to its excellent corrosion resistance to acidic condensate, light weight, and ease of cutting and solvent-welding, making installation efficient and cost-effective.
Why the other options are wrong
- A. Cast iron is heavy, expensive, and not typically used for small-diameter condensate lines, and can corrode.
- B. Copper can be corroded by acidic condensate over time, especially if the pH is low.
- C. Galvanized steel pipe is highly susceptible to corrosion from acidic condensate, leading to blockage and failure.
Condensate Drain Pipe Material
The material used for pipes that carry away condensate from HVAC equipment, dehumidifiers, or high-efficiency furnaces.
- Condensate is often slightly acidic, requiring corrosion-resistant materials.
- PVC is the most common and cost-effective choice due to its chemical resistance and ease of installation.
- CPVC can be used for higher temperature condensate applications.
- Copper, galvanized steel, and cast iron are generally unsuitable due to corrosion.
Memory trick: Acidic drip, PVC grip, no metal slip.