Boiler Repair

Hot-water and steam boilers — circulators, leaks, ignition, controls. Same-day diagnosis from techs who actually work on boilers every week.

  • Same-day service
  • 24/7 emergency dispatch
  • Flat-rate, upfront pricing
  • Home Comfort Guarantee

Boiler Repair

Boilers fixed by techs who actually know boilers.

Boilers are less common than furnaces in the Inland Northwest, which means most HVAC companies aren’t truly set up to service them. We are. Our techs are trained on hot-water (hydronic) and steam boilers from Weil-McLain, Burnham, Lochinvar, Navien, Buderus, and the rest of the major brands.

From a single-zone leak to a multi-zone system that won’t fire, we diagnose, quote a flat-rate repair, and back it with a written warranty.

  • Hydronic specialists Hot-water boilers, baseboard, in-floor radiant, and steam systems.
  • Stocked trucks Circulators, expansion tanks, ignition modules, and zone valves on board.
  • Flat-rate quotes Approved before any work — never charged by the hour.
  • Warrantied work 1-year labor warranty plus full manufacturer parts coverage.

Symptom Check

Signs your boiler needs service

Boilers tend to fail slowly — small problems become floods or no-heat emergencies if ignored.

  • Leaks or wet floor

    Even slow leaks indicate failing seals, expansion tanks, or pressure-relief issues.

  • Cold radiators

    Air-locked zones, failed circulators, or stuck zone valves.

  • Banging or kettling noise

    Mineral scale buildup or air in the system — both shorten boiler life.

  • Pressure problems

    Pressure too high or too low usually points to expansion tank or fill valve issues.

  • Won't ignite

    Pilot light, ignition module, gas valve, or thermocouple — diagnosed in one visit.

  • High gas bills

    A boiler that's working harder than it should usually shows up on your bill before it shows up in comfort.

What We Repair

Every common boiler issue

Hot-water, steam, gas-fired, oil-fired, and high-efficiency condensing boilers — repaired by techs who know them.

  • Circulator pumps Replace failed circulators that move hot water through the system.
  • Zone valves Stuck or failed zone valves — common cause of "one zone won't heat".
  • Expansion tanks Replace waterlogged tanks and fix repeating pressure-relief issues.
  • Ignition & pilot Modern modules, hot-surface igniters, and standing-pilot thermocouples.
  • Pressure relief & fill Failed PRVs, blocked fill valves, and overpressure problems.
  • Aquastats & controls Replace failing temperature controls and outdoor-reset modules.
  • Air-locked zones Bleed and rebalance hydronic zones that have lost circulation.
  • Combustion safety check Combustion analysis and CO testing on every gas-fired boiler.

How It Works

Our 4-step boiler repair process

No mystery, no pressure. Here's exactly what to expect.

  1. Call & schedule

    Speak to a real dispatcher 24/7. We confirm a time window and text a tech photo.

  2. Diagnose

    Pressure, ignition, circulators, zones, and combustion — checked and reported.

  3. Approve the price

    Flat-rate quote in writing. The diagnostic fee is applied to the repair.

  4. Fix & guarantee

    Most repairs done same-day. 1-year labor warranty plus parts coverage.

Why Choose Mainstream

Same-Day Service

Most service calls handled same-day across Spokane and Coeur d'Alene.

Upfront Pricing

Flat-rate pricing approved before work begins — no surprises on the invoice.

Licensed & Insured

Fully licensed in Washington and Idaho, bonded, and insured for your protection.

Satisfaction Guaranteed

If it isn't right, we make it right. Period.

Boiler trouble? We can help.

Same-day service across Spokane & Coeur d'Alene — flat-rate pricing, no surprises.

What Our Customers Say

Don't just take our word for it — hear from our satisfied customers

C Claudia Johnson
Claudia Johnson 4 hours ago
★★★★★
Ricky Saldana the technician that came out was fantastic. He was so knowledgeable about my plumbing issues and his recommendations were spot on. He was on time and very pleasant to work with. I would highly recommend him for any plumbing work that needs to be done. Thanks Ricky for all of your input.
S Sharon Scott
Sharon Scott 5 hours ago
★★★★★
Jake was on time and very good about looking at my furnace. I appreciate all his help. I reccomend him and mainstream electric very highly. thank you Sharon Scott
S Steve Holding
Steve Holding 8 hours ago
★★★★★
Great work

Maintenance Membership

Join the Care Club

Total home service care, on a schedule.

Members get priority scheduling, seasonal HVAC tune-ups, an annual plumbing & electrical safety inspection, and exclusive discounts — for less than the cost of a single emergency call.

  • Priority scheduling
  • Seasonal HVAC tune-ups
  • Annual safety inspection
  • Exclusive member discounts
  • Free dispatch on repairs
  • No long-term contracts

Boiler Repair — Frequently Asked Questions

Why is my boiler losing pressure?

Most common cause is a leak somewhere in the system — a circulator seal, a baseboard fitting, or a relief valve that’s passed water. The second most common cause is a waterlogged expansion tank that no longer absorbs system pressure swings. Both are fixable in a single visit.

Why is one zone not heating?

Almost always a zone valve, an air-locked zone, or a failed circulator pump. We can usually pinpoint and fix the issue in a single visit — including bleeding the zone if it’s air-locked.

Should I repair or replace my boiler?

Modern condensing boilers run at 95%+ efficiency vs. 70–80% for older atmospheric boilers — the energy savings can pay back a replacement faster than you’d expect. If your boiler is over 15 years old and you’re facing a major repair, we’ll model the math both ways.

Do you service tankless / combi boilers?

Yes — including Navien, Rinnai, and Lochinvar combi boilers that handle both space heating and domestic hot water. These systems have unique service needs (descaling, flow sensors, plate heat exchangers) and not every company is set up for them.

Is the repair warrantied?

Every repair includes a 1-year Mainstream labor warranty plus the full manufacturer parts warranty. Care Club members get a 2-year extended labor warranty.

*Offers cannot be combined with other promotions or applied to dispatch fees. No cash value. Must present offer at time of service. Call for details.

Ready when you are.

Same-day service across Spokane and Coeur d'Alene. Licensed in WA & ID, fully insured, satisfaction guaranteed.

(509) 237-6483 Book Now
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