Lochinvar warranty tiers vary significantly by product family. Unlike standard tank brands where a 6/9/12-year tier corresponds to a single number, Lochinvar combi boilers and commercial units have warranty conditional on annual professional service.
| Product | Heat Exchanger / Tank | Parts | Labor |
|---|---|---|---|
| NOBLE Combi (NKC) | 5 years | 1 year | 1 year |
| KNIGHT Combi (WHN) | 10 years | 1 year | 1 year |
| SQUIRE Glass-Lined (SIT) | 10 yr residential / 5 yr commercial | 1 year | 1 year |
| SQUIRE Stainless (SSU) | Lifetime residential / 10 yr commercial | 1 year | 1 year |
| AWHP Heat Pump | 10 years | 1 year | 1 year |
| EnergyRite Commercial | 5 years | 1 year | 1 year |
| ARMOR Commercial | 5 yr (10-yr extended available) | 1 year | 1 year |
Annual service requirement (critical)
NOBLE, KNIGHT, ARMOR, and the larger EnergyRite require annual professional service to keep warranty active. Skipping service voids the heat exchanger warranty — and the heat exchanger is the most expensive component. Budget $300-500/year. Service must include: heat exchanger inspection, condensate trap cleaning, combustion analysis with CO/O2 verification, and signed service record retained for warranty claims.
Registration
- Online at lochinvar.com within 60 days of install
- Contractor often handles this on the homeowner\'s behalf
- Without registration, warranty defaults to manufacture date
What voids the Lochinvar warranty
- No annual service on combi or commercial condensing — biggest cause of denial
- DIY install on combi boilers — must be installed by a licensed contractor in most jurisdictions
- Improper venting — wrong pipe diameter, exceeded equivalent length, condensate trap not primed
- Hard water on plate heat exchanger without water softening or annual descaling
- Aggressive water on glass-lined SIT — stainless SSU recommended for chloride/sulfate-aggressive wells
- Closed expansion loop without proper expansion tank sizing
How to register
lochinvar.com → "Warranty Registration" → enter serial number, install date, installer contact. Save the confirmation email.
Bottom line
Lochinvar warranty is contractor-channel — install, service, and claims all go through the contractor and Lochinvar tech support, not direct-to-consumer. Annual service contract is the single most important warranty action. SQUIRE Stainless residential lifetime is the strongest warranty in the lineup; NOBLE 5-year heat exchanger is the shortest among condensing combi brands.