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BOILERS · RADIANT FLOOR · HYDRONIC ZONES · SNOW-MELT

Boilers & Hydronic Systems

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Annual boiler service, no-heat emergencies, full hydronic system design, radiant floor install, indirect water heaters, and snow-melt slabs. Combustion analysis on every visit. Triangle Tube · Lochinvar · Weil-McLain · Burnham · Taco · Grundfos certified.

  • Annual boiler service
  • Emergency no-heat diagnostics
  • Combustion analysis reports
  • Radiant floor systems
  • Hydronic zone & manifold work
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Boilers & Hydronic Systemsoverview

Boilers and hydronic systems are the second-largest piece of what we do — and the place where we most commonly get called as the second opinion. General plumbers and HVAC techs misdiagnose hydronic systems all the time because the failure modes are different from forced-air heat. About one in five of our boiler calls is a customer who already paid someone else and is still cold. We carry common Triangle Tube, Lochinvar, Weil-McLain, and Burnham parts on the truck for first-trip repair, and we design and install full hydronic systems from blueprint through commissioning.

If you are not sure whether you have a boiler: you have one if your house heats with hot water rather than air. Telltale signs are a small wall-mounted unit (mod-con condensing boiler) or a refrigerator-sized cast-iron unit in the basement, copper or PEX lines running to baseboard radiators or a manifold for a radiant floor, and quiet heat that you feel in the floor or along the baseboard rather than blowing out of vents. Boilers run cleaner, last longer, and cost more upfront than a furnace — and in North Idaho's deep cold, they are worth it.

This page covers what kinds of boilers and hydronic systems we install and service, how radiant floor heating actually works (and which retrofit options make sense in an existing home), what an annual service includes and why it matters, and what the typical install ranges run.

Types & Options

Every option, spelled out.

01

Mod-Con (Modulating Condensing) Boilers

High-efficiency wall-hung — the modern default

A modulating condensing boiler is the modern default for residential hydronic heat. It modulates its firing rate to match the heat demand (rather than cycling on-off like older boilers), and it captures heat from the flue gases for a second efficiency pass — running 92–96% AFUE compared to 80–84% on a non-condensing unit. Most are wall-hung, about the size of a large kitchen cabinet, and vent through PVC or polypropylene rather than a chimney.

We install Triangle Tube Prestige, Lochinvar Knight, Weil-McLain Evergreen, and HTP UFT series most commonly. The choice depends on building heat load, domestic hot water requirements, fuel (natural gas vs. propane), and whether the system is open or sealed combustion. We do a Manual J-style heat loss calculation as part of any new install or replacement quote — a properly sized boiler runs longer at lower fire and lasts longer; an oversized boiler short-cycles and dies young.

  • Efficiency: 92–96% AFUE
  • Modulates from 20% to 100% firing rate based on heat demand
  • PVC or polypropylene venting (no chimney required)
  • Lifespan: 15–20 years with annual service
  • Brands we install: Triangle Tube, Lochinvar, Weil-McLain, HTP
Best fit

Most North Idaho residential and small commercial installs. New construction, full system replacements, and homes upgrading from a 30-year-old cast-iron boiler.

02

Cast-Iron Boilers

Old-school workhorse — still has a place

Cast iron boilers are the traditional residential boiler — large, heavy, and built to last 30+ years. They run at 80–84% efficiency and require a chimney for venting. We do not install many new cast-iron units anymore (mod-con is more efficient and easier to vent), but we service plenty of existing ones, especially in older Sandpoint and Bonners Ferry homes built before the mod-con era. A well-maintained cast-iron Burnham or Weil-McLain from the 90s often outlasts the homeowner.

When a cast-iron boiler finally needs replacement, the right answer is usually a mod-con plus rezoning — but not always. Homes with high-mass radiator baseboards or wide design temperature swings sometimes benefit from sticking with cast iron. We do not push you to mod-con just because the rebate is bigger.

  • Efficiency: 80–84% AFUE
  • Chimney venting (existing chimney usually works)
  • Lifespan: 30+ years on cast-iron heat exchanger
  • Brands we service: Burnham, Weil-McLain, New Yorker
  • Replacement decision: usually mod-con, sometimes cast-iron-for-cast-iron
Best fit

Older homes with existing chimneys, high-mass radiator baseboards, and owners who prioritize reliability and longevity over efficiency.

03

Radiant Floor Heating Systems

Heat from the floor up — the most comfortable heat you can buy

Radiant floor heating runs warm water through PEX tubing under the floor, turning the entire floor into a low-temperature radiator. Done right, it is the most comfortable heat available — even temperatures floor to ceiling, no drafts, no dust circulating, no cold spots. It also pairs well with mod-con boilers because radiant runs at low water temperatures (95–115°F) which is exactly where a condensing boiler is most efficient.

There are three install methods. Slab-on-grade is the gold standard: PEX tubing tied to rebar in the slab before the concrete pour, integrated into a new build or a major remodel. Above-grade plywood-staple-up is the residential retrofit method: the PEX is fastened to the underside of the subfloor with reflective insulation behind it. Above-grade overlay (Warmboard, etc.) is for retrofits where you can lose 5/8 to 7/8 inch of finished floor height — the PEX runs in grooved aluminum-clad panels that sit on top of the existing subfloor.

We design the loop layout based on heat-loss calculations per room, install the manifold and zone valves, pressure-test the system, and tie it back to a properly-sized boiler with mixing valves to keep floor temperatures safe (you do not want 180° water under hardwood). For new construction we work directly with the GC; for retrofits we work around the homeowner's schedule. Either way, an annual flush of the loops keeps the system running for 30+ years.

  • Three install methods: in-slab, staple-up retrofit, above-grade overlay
  • Operating temperature: 95–115°F (perfect for mod-con boiler efficiency)
  • Zone-by-zone control: separate temperature per room
  • Pairs with: tile, hardwood (engineered preferred), polished concrete, LVT
  • Lifespan: 30+ years on the tubing; manifold/valves replaceable
Best fit

New construction, additions, master-bath remodels, basement finish-outs, and anyone who has stood on a heated bathroom floor in February and not wanted to leave.

04

Snow-melt Systems

Driveways, walkways, and stairs that clear themselves

Snow-melt systems use the same PEX-and-glycol setup as radiant floor heating, but installed under driveways, walkways, and stair treads. A dedicated boiler (or a heat exchanger off the home boiler) circulates warmed glycol through the slab; an automated controller fires the system when sensors detect snow or freezing rain. North Idaho winters make snow-melt one of the more popular custom-home upgrades on lake-side and Schweitzer-area properties.

We design and install snow-melt for driveways, walkways, and porch slabs. The math matters: a snow-melt slab needs 100–150 BTU per square foot at design conditions, so a 600-square-foot driveway can pull 90,000 BTU — enough to require a dedicated boiler in some installs. We size the system and pair it with the right glycol blend so it does not freeze when the heat is off.

  • BTU demand: 100–150 BTU/sq ft at design conditions
  • Glycol-water mix prevents freezing during off-cycle
  • Automated controller fires on snow/temp sensor
  • Common applications: driveways, walkways, porch slabs, exterior stairs
Best fit

Custom homes, steep driveways, lake-house entrances, and anyone done with a snowblower at 6am.

05

Indirect-Fired Water Heaters

Use your boiler to make domestic hot water

An indirect-fired water heater is a storage tank with no burner — instead, a coil inside the tank is heated by water from your boiler. If your home is already heating with a boiler, adding an indirect tank is the most efficient way to make domestic hot water — the boiler is already there, already running, and runs at higher efficiency for water heating than a standalone gas tank would.

We install Triangle Tube Smart, Bradford White Hydrojet, and HTP Superstor indirect tanks most commonly. They are tall stainless-lined tanks (40, 60, or 80 gallons) that sit next to the boiler and connect via a small zone of the heating loop. Installed correctly with priority zoning, they make 60+ gallons of hot water per hour using a fraction of the energy of a standalone tank.

  • Pairs with any mod-con or cast-iron boiler
  • Capacities: 40 / 60 / 80 gallon stainless-lined
  • Recovery: 60+ gph (faster than standalone gas)
  • Lifespan: 20+ years (no internal burner to fail)
  • Best for: hydronic homes — uses heat you are already making
Best fit

Any home that already heats with a boiler and wants the most efficient domestic hot water possible.

Sizing Guide

Pick the right size.

Boiler and hydronic sizing is more complex than tank water heater sizing — it depends on heat-loss per room, design outdoor temperature, distribution system (baseboard vs. radiant vs. mixed), and domestic hot water demand. Here is the rough framework, but every install gets a real heat-loss calc.

Household / Use CaseWhat we typically size for
1,500–2,000 sq ft, baseboard heat80–110 MBH mod-con boiler · 2–3 zones
2,500–3,500 sq ft, mixed baseboard + radiant120–150 MBH mod-con · 4–5 zones · indirect tank
4,000+ sq ft, radiant + DHW + snow-melt150–199 MBH primary + secondary loops · 6+ zones · dedicated snow-melt boiler often required
Cabin / 800–1,200 sq ft60–80 MBH mod-con or hydronic-air handler · 1–2 zones
Lake-house / hospitality (5,000+ sq ft)Cascading mod-cons (multiple boilers in lead-lag) · zoned · indirect + recirc

Oversizing is the most common boiler mistake — short-cycling kills heat exchangers. We size on heat loss, not on square footage rules of thumb.

When to call us

Warning signs don't ignore.

No heat / cold radiators

Could be a stuck zone valve, failed circulator, frozen condensate trap, low system pressure, or a locked-out boiler. We diagnose on the truck — most no-heat calls are same-visit fixes.

Boiler short-cycling (firing every few minutes)

Oversized boiler, dirty heat exchanger, scaled water side, or failed sensor. Short-cycling cuts boiler lifespan in half. Annual service catches this.

Loud banging in pipes (water hammer / kettling)

Air in the system, scaled heat exchanger boiling water in the unit (kettling), or loose pipe hangers. Service includes a system flush and bleed.

Condensate leak under boiler

Mod-con boilers produce condensate water. A clogged trap, cracked drain line, or failed neutralizer dumps acidic water on the floor. Easy fix when caught; concrete-eating if ignored.

Pressure relief valve dripping

Expansion tank waterlogged or system over-pressurized. Easy fix; potentially expensive if the PRV blows fully and dumps the system.

Boiler over 20 years old

Cast iron boilers can last 30+ but the auxiliary controls (circulators, zone valves, sensors) often fail well before. A pre-emptive service tune-up or planned replacement beats a January no-heat call.

Brands We Install

Why these brands.

Triangle Tube

Belgian engineering, made in NJ. Prestige series mod-con boilers and Smart indirect tanks are our most-installed combo in North Idaho. Heat exchangers warranted for life on residential.

Lochinvar

American mod-con leader. Knight series for residential, Crest for commercial. Excellent service availability and parts support.

Weil-McLain

Long-standing American boiler maker. Evergreen mod-con and the Aqua Logic cast-iron line — both we install and service regularly.

Burnham (US Boiler)

Cast iron heritage. Many older Sandpoint homes have a 90s-era Burnham still running fine. We service these and stock common replacement parts.

Taco

Circulator pumps and zone valves. Taco 007 and 0010 are the workhorse residential circulators we install everywhere.

Grundfos

Premium circulator pumps, especially the Alpha variable-speed line for smart-zoning systems and high-efficiency installs.

We pick the unit based on what fits your home, not what brand has the biggest rebate this month.

Scope · What's Included

Exactly what we cover.

Boiler and hydronic scope varies more than water heaters because the systems are bigger and the install paths range from a single circulator swap to a full whole-home rebuild. We do not post fixed prices because the right number for your home depends on heat-loss, distribution, fuel, and existing infrastructure. Here is what we include in every category we install:

Annual boiler service + combustion analysis
Sediment flush, condensate trap clean, combustion report, zone valve test, expansion tank check, anode inspection where applicable, written service log.
No-heat emergency diagnostic
Same-day priority dispatch in Bonner County. Diagnostic fee disclosed before dispatch and credited if you proceed with the repair.
Mod-con boiler replacement (residential)
Includes heat-loss calculation, new venting, condensate handling, zoning rework if required, and full commissioning report.
Indirect-fired tank install (paired with existing boiler)
Stainless tank, priority zone tie-in, mixing valve, and recirculation logic where applicable.
Radiant floor — staple-up retrofit
Per-zone install: PEX, fasteners, reflective insulation, manifold, mixing valve, controls. Insulation extra if needed.
Radiant floor — slab-on-grade (new build)
Tubing tied to rebar before pour, manifold, controls. Most cost-effective install method when integrated with the slab pour.
Snow-melt slab (driveway / walkway)
Glycol-and-PEX in slab, snow/temp sensor controls, dedicated boiler if heat load exceeds main boiler capacity.
Zone valve / circulator pump replacement
Most done same-trip on truck-stocked parts (Taco, Grundfos).

We pull permits, register manufacturer warranties, and provide a written labor warranty on every install. Annual maintenance contracts available for residential and commercial accounts. All quotes are in writing before any work begins.

Our Process

Three steps. Zero surprises.

1

Heat-loss calculation + system audit

We measure your home's actual heat loss room by room, audit the existing distribution (radiators, baseboards, manifold), and identify any installed-wrong items the previous installer missed.

2

Written design + quote

Boiler model, BTU sizing rationale, zoning layout, circulator selection, controls strategy, and the all-in price. Multiple options where they make sense (e.g., mod-con vs. cast-iron). No verbal quotes.

3

Install, commission, document

Pull permit. Install to spec. Commission with combustion analysis report and printed startup log. Register manufacturer warranties. Train you on the controls. Hand you a written labor warranty and the service log.

Boilers & Hydronic SystemsFAQ

My boiler is not heating — can you come today?+
Yes. No-heat diagnostics are priority dispatch in winter. We carry common Triangle Tube, Lochinvar, Weil-McLain, and Burnham parts (circulators, zone valves, ignitors, sensors, condensate traps) for first-trip repair when possible.
What does an annual boiler service include?+
Combustion analysis report, condensate trap and neutralizer clean, pressure relief valve test, expansion tank pressure check, circulator pump inspection, zone valve operation test, anode rod check (where applicable), venting and draft check, and a written service log that lives with the system. About 90 minutes for a residential mod-con.
Do you design and install full hydronic systems?+
Yes — boiler selection, sizing, zoning layout, manifold design, radiant floor install, indirect tank, snow-melt, and commissioning. Whether it is a remodel adding one zone or a new build with five zones plus a snowmelt slab, we design and install from scratch.
Can radiant floor heating be retrofitted into an existing home?+
Yes, two ways: staple-up under the existing subfloor (works if you can access the joist bays from below — basement ceiling, crawlspace) or above-grade overlay panels like Warmboard (raises the finished floor 5/8–7/8 inch). We assess the access on-site before quoting either method.
Is radiant floor heating worth the upfront cost?+
If you are doing new construction or a major remodel where the floor is already coming up, yes — the labor incremental is small and you get a generation of comfort upgrade. As a pure retrofit it is more nuanced; we look at the existing heating system, the heat loss, and the floor finishes you already have before recommending it.
What kind of boiler should I install in North Idaho?+
For most residential, a mod-con condensing boiler — Triangle Tube Prestige, Lochinvar Knight, or Weil-McLain Evergreen. They run at 92–96% efficiency, modulate to match heat load, and pair perfectly with low-temperature radiant. Cast-iron is still appropriate for some older homes with high-mass radiators or no easy venting path.
How long does a boiler last?+
Mod-con: 15–20 years with annual service. Cast iron: 30+ years. Both depend heavily on water quality (a system filled with un-conditioned water scales the heat exchanger fast) and on regular maintenance. A neglected mod-con can die in 8 years; a maintained one runs to 20+.
Why does my boiler short-cycle?+
Most common: it is oversized for the heat load. Other causes: scaled heat exchanger, failed temperature sensor, undersized expansion tank, or zone configuration that pulls too little flow at low demand. Short-cycling kills boilers — annual service catches it.
Do you do snow-melt driveways?+
Yes. We design and install snow-melt slabs from 100 sq ft walkways up to full circular driveways. The system is glycol-and-PEX in the slab, tied to a dedicated boiler or a heat exchanger off the home boiler, automated by a snow-and-temp sensor.
What is the difference between hydronic heat and forced-air?+
Forced-air heats air and blows it through ducts; hydronic heats water and circulates it through pipes (to baseboards, radiators, or radiant floors). Hydronic is quieter, has even temperatures floor to ceiling, no dust circulation, and works at low water temperatures that pair with mod-con efficiency. Forced-air is cheaper to install and integrates with central AC. North Idaho's deep cold and dry winters make hydronic the better long-term choice for most.
Can I add air conditioning to a hydronic-heated home?+
Yes — the most common path is a separate ductless mini-split AC system (Mitsubishi, Daikin) for cooling, leaving the hydronic in place for heat. We do not install AC ourselves, but we coordinate with HVAC partners on full-stack designs.
Do you service older boilers, or only install new ones?+
Both. We service every brand we install plus older units (Burnham, Weil-McLain, New Yorker, Slant/Fin, Buderus). About a third of our boiler work is service on existing systems, including diagnostic-and-repair on the no-heat calls every winter.

Boilers & Hydronic Systems across North Idaho

We service every city below. Click your town for the local details, or just call us — we'll confirm coverage in 30 seconds.

Other Services

We do four other things, too

Boilers and hydronic are where the second-opinion calls come from. If your heat is not working right, call us — we have probably seen the failure mode, and we have the parts on the truck more often than not.

Call (208) 304-7247 for service, no-heat emergencies, or to schedule a hydronic system design consult. Same-day priority dispatch for active no-heat calls.

Need boilers & hydronic systems? Call us. We're a real family business.

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