About Lochinvar in Utah homes
Lochinvar has become the dominant condensing mod-con brand in our Park City, Heber, Cottonwood Heights, and Draper service areas over the past decade. There are a few reasons: strong reliability track record, competitive pricing on the Knight line, broad availability through Salt Lake distributors, and a product range that scales from small residential up through light commercial without forcing a brand switch.
For the kind of large custom homes that dominate Park City and the Wasatch Back — with multi-zone radiant, indirect hot water tanks, and often integrated snow-melt — the Lochinvar Knight + SquireXL indirect tank combination is the package we install most often. It's a well-engineered system that, when properly commissioned and maintained, runs 15-20 years without major issues.
Lochinvar models we service
Knight (KBN, KHN, KBH) — the workhorse mod-con
The Knight is Lochinvar's residential heat-only condensing boiler line. 95%+ AFUE. 5:1 modulation ratio. Stainless steel heat exchanger. The KBN was the original Knight; the KHN is the current residential generation with refined controls and a smaller footprint. The KBH is the heat-and-DHW variant designed for pairing with an indirect tank for DHW. We service all generations dating back to the early 2010s.
KHB — Knight combi
The combi version. Heat plus domestic hot water from a single wall-mounted unit. Same heat exchanger and control technology as the Knight, with the addition of a plate exchanger for instantaneous DHW. Good fit for smaller homes (under 2,800 sq ft) where the simultaneous hot water demand is manageable. Less common in Park City custom homes but common in Salt Lake townhouses and smaller new construction.
Crest — commercial-residential
The big brother of the Knight. Higher BTU output (up to 6,000,000 BTU on the largest models). We install Crest units in larger custom homes (5,500+ sq ft with extensive radiant and snow-melt loads) and in light commercial buildings — offices, multi-family, small commercial spaces. Same control logic as the Knight, scaled up.
SquireXL indirect water heater
Not a boiler, but worth covering since it's the most common DHW pairing with a Knight. The SquireXL is Lochinvar's stainless-steel indirect tank — heated by the boiler, dramatically faster recovery than a standalone water heater. Common in Park City homes where DHW demand is high (large families, multiple bathrooms).
Common Lochinvar issues we see in Utah
Flame rod fouling
The single most common Knight service call. The flame rod (which detects whether the burner is lit) fouls with combustion deposits over time. Symptoms: occasional ignition lockouts, eventually failure to light at all. Fix: clean the flame rod to manufacturer spec, verify gap and position. We do this on every annual maintenance to prevent it from ever becoming a no-heat call.
Altitude combustion drift
Park City and Heber Knight installations from the past 10 years — particularly those installed by generalist HVAC companies — were often never properly derated for altitude. The result is units running rich, fouling flame rods 3x faster than they should, producing measurable CO. We retune to Lochinvar's published altitude tables on first service. Often a single visit resolves multiple "weird issues" the owner has been living with.
Condensate freeze in cold-weather installs
Knight boilers produce a few gallons of acidic condensate per day at high load. In Park City installs where the condensate line runs outdoors or through unconditioned space, the line can freeze on cold nights, back the condensate up into the heat exchanger, and trigger a safety lockout. Fix: heat-traced condensate routing, or moving the discharge to an interior floor drain.
Lockout codes — diagnosing properly
Knight boilers display specific numeric fault codes that point to the failure. Common codes we see: 12 (ignition failure — usually flame rod), 16 (high limit — usually scale on HX), 78 (gas pressure — needs verification), and 105 (low water pressure — leak somewhere). The codes are diagnostic shortcuts; reading them properly saves significant time on every service call. Many generalist techs just clear the code and hope.
Scale buildup on heat exchanger
Stainless heat exchangers are less prone to scale than aluminum, but Utah's hard water still causes scale buildup over years. Symptoms: rising stack temperature on combustion analysis, declining heat output, eventual lockout on overheating. Periodic chemical clean (every 5-7 years on hard-water systems) addresses it. Magnetic dirt separator at the boiler helps significantly.
Control board firmware issues
Older Knight control boards (pre-2018) occasionally have firmware quirks that produce intermittent symptoms — unexplained shutdowns, sensor errors that come and go, modulation issues. Lochinvar publishes firmware updates and service bulletins; sometimes a control board upgrade resolves issues a parts-cannon approach wouldn't.
"If we had to install one mod-con line across Park City for 20 years, it would be the Knight. The combination of reliability, parts availability, and altitude tolerance is hard to beat at the price point."
When to repair vs replace
- Knight under 10 years old: Almost always worth repairing. Parts are current, the unit has years left.
- Knight 10-15 years old with normal wear items: Repair. Igniter, flame rod, gas valve, control board — all routine replacements.
- Knight 15+ years old with heat exchanger issues: Case-by-case. If under warranty (12 years on HX, sometimes longer with registration), HX may be covered. Outside warranty the math often favors replacement.
- KBN units (oldest Knight generation): Parts are getting scarcer. Repair is often still possible but the math sometimes favors a Knight KHN replacement.
- KHB combi: Same age math as Knight. Watch for scale on the plate exchanger — it's the most common KHB failure mode.
Service rates
Standard rates apply. See our boiler repair pricing for full ranges. Lochinvar-specific common items:
- Diagnostic + combustion analysis: $129–$189
- Flame rod cleaning + verification: $220–$320
- Igniter replacement: $260–$420
- Gas valve replacement: $620–$1,100
- Control board replacement: $720–$1,400
- Annual maintenance: $269–$349
- Altitude commissioning / re-tune (one-time): $189–$289
Where we service Lochinvar boilers
All 26 cities. Highest density in Park City, Heber Valley, Cottonwood Heights, Draper, and the foothill custom-home markets. Full service area list →