Homes in a Maple Grove HOA, built more than ten years ago, started leaking at the fittings where the water supply lines tie into the fire sprinkler system. Several plumbers visited each home. Some said they could not fix it. Others quoted $3,000 or more. The homeowners were left with a leak, multiple quotes, and no clear path forward.

We were contacted about it. Here is what was causing the leaks, why repairs stalled, and how we helped the homeowners get a real fix instead of leaving them out to dry.

What was causing the leaks

The piping where the household water supply meets the sprinkler system was a mix of brass and galvanized steel. When two different metals touch and water is present, one of them corrodes faster than the other. That is galvanic corrosion, which plumbers often call electrolysis. Over years, it eats away at threads and fittings until the joint weeps or drips. The homeowners initially thought it was a water pressure issue, but the final assessment was that electrolysis was the culprit.

Around these fittings, the corrosion had progressed to active leaks. If you have a similar connection, watch for:

• Crusty green, white, or rust-colored buildup at threaded joints
• Weeping or dripping at a fitting, even a slow drip
• Damp drywall, flooring, or staining near the sprinkler tie-in
• A drop in water pressure at fixtures

If you see these signs, avoid cranking a wrench on a corroded fitting. Overtightening can crack it and turn a slow leak into a bigger one.

Why so many repairs stalled

The last fitting in this connection is part of the fire sprinkler system. In Minnesota, work on fire protection systems must be done by or under the supervision of a certified sprinkler fitter. State licensing rules carry no general exemption for plumbers, and the state's guidance is that plumbers cannot perform general sprinkler installation or modification. There is a narrow exception for multipurpose potable water piping systems, which does not cover this.

So, a plumber can often fix much of the run but cannot touch the final connection. That is one reason a plumbing-only fix might not resolve the entire issue. We cannot speak for what other companies were told or what they could do, but we can explain why we hit the same wall.

What we did about it

We inspected one of the homes and gave the homeowner an estimate. Then, we realized that as plumbers we could not touch the last fitting. Rather than give the homeowners a partial fix, we called a fire suppression specialist at a large local company and asked how the job should be handled.

He advised us on the repair. He also told us his company would be expensive, so he referred us to two other fire suppression companies. We reached out to two additional fire suppression companies then requested quotes from two of them. The quote we received was in a similar range as ours, with one important difference: the sprinkler contractor would replace all of the affected piping in brass, including the final connection, whereas our plan would have covered all but the last fitting (a thorough but incomplete repair).

We passed the estimate along and coordinated a warm handoff to the homeowners. We did not ask for a referral fee, a subcontractor fee, or anything else in exchange. The goal was for the homeowners to get the problem solved by the right people.

What we took from it

• Know where your license ends, and say so. Telling a customer "we cannot touch that part" is better than pretending a partial fix is a full one.
• Ask for a scope that covers the whole connection. The homeowners needed a plan that dealt with the final fitting, not only the piping leading up to it.
• Follow up. We want to help homeowners solve their problems, even if it’s outside of our scope of capability. Following through on communication and establishing long-term relationships with property owners is important to us, even if we don’t get paid for it.

What HOA boards and homeowners should do

1. Document the pattern. Photograph each issue, note the date, and list which homes are affected. A pattern across homes is a sign of a shared cause.
2. Ask contractors whether they’re licensed to do the work. Ensure your contractor is licensed, insured, and bonded, so you know your home and the work is protected.
3. Ask about permits, inspection, and water shutoff. Confirm whether the work requires these, who’s coordinating, and who’s paying for them.
4. Compare full scopes, not just the numbers. A lower quote isn’t always the best solution. Ask follow up questions and compare apples to apples on what you’re getting.
5. Report any water damage to your insurance promptly, even if you expect to pay for the repair yourself.