Q: Why does condensate need to be neutralized?
A: Condensate from high-efficiency boilers is mildly acidic — often between pH 3 and 5. If drained directly, it can corrode cast iron, copper, and even PVC over time. Most plumbing codes require the use of a neutralizer filled with limestone or magnesium pellets to bring the pH closer to neutral (7) before disposal.
Q: Why is my setup difficult to work with?
A: Since your Alpine boiler outlet is only 7 inches above the floor and the pump top is 4 inches high, there’s barely enough drop for gravity flow through a standard inline neutralizer. These units are typically 8 to 12 inches long and require 3 to 4 inches of slope to drain properly.
Q: What can I do in tight spaces?
A: You have several options:
- 1. Use a compact horizontal neutralizer: Products like the Saniflo Sanicondens Best or DiversiTech CN2 combine neutralization and pumping in one compact body.
- 2. Remote-mounted neutralizer: Mount a small canister on the wall just above the pump’s intake. Route the condensate up a few inches through tubing using a check valve to prevent backflow.
- 3. DIY short-tray neutralizer: Create a shallow horizontal box using PVC pipe or fittings filled with neutralizing media (limestone chips). Keep it as close to the pump as possible to maintain flow.
Q: Can I put the neutralizer after the pump?
A: No. The acidic water will damage the pump’s impeller and housing over time. Always neutralize before the condensate enters the pump.
Q: How often should neutralizer media be replaced?
A: Typically every 6–12 months, depending on usage. If you see white buildup or reduced flow, it’s time to replace the pellets. Keep an eye on the pH of the discharge water — it should be above 6.0.
Q: What’s the best long-term solution?
A: If you ever upgrade or relocate the boiler, mount it higher on the wall to provide more fall for a full-size neutralizer. This simplifies maintenance and keeps your system compliant with code.
For a professional guide on neutralizing condensate and product options, see Caleffi’s guide to condensate neutralization.
I’m Chris Mayer, writing for Plumbing 101.