Viessmann CU3A-160 Vitocrossal 300 CU3A 160,000 BTU Gas Condensing Boiler
by Viessmann
HardwarePlumbingPlumbing Fittings & Supports
| Manufacturer part number | CU3A-160 |
|---|---|
| Plumbing Deals SKU | VIESCU3A160 |
| Availability | In stock at Plumbing Deals, as of 18 Oct 2026 |
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Description
From Plumbing Deals' product listing.
Right-Size Your Heat With Viessmann CU3A-160 Vitocrossal 300 160 MBH Floor-Standing Condensing Boiler Need steady, high-temperature comfort without the fuel waste? The Vitocrossal 300 CU3A-160 is a floor-standing gas-fired condensing boiler that combines a high-mass stainless Inox-Crossal heat exchanger with a modulating MatriX dome burner for quiet, even heat and 95% AFUE—ideal for cast-iron radiator retrofits and multi-zone fin-tube systems. Brand: Viessmann MPN: CU3A-160 Type: Floor-Standing Gas-Fired Condensing (Heat-Only) Hydronic Boiler Size/Capacity: 43–160 MBH input; Net AHRI 129 MBH; 95% AFUE Material/Finish: Stainless-steel Inox-Crossal heat exchanger; MatriX modulating dome burner Performance: Sound 53 dB (max) / 33 dB (min); condensate up to ~1.6 USG/h; boiler water content 18.8 USG; altitude operation to 10,000 ft (de-rate applies) Connections/Fit: Heating supply/return 1¼" NPTM; PRV ¾" NPTF; boiler drain 1" NPTM; gas ¾" NPTF; direct-vent; 4" flue / 3" combustion air; allowable vent lengths up to ~198 ft (layout-dependent) Dimensions: 61.5"–67" H × 26" W × 31.5" D Included: Vitotronic 200 outdoor-reset control with outdoor sensor; installation fittings with 30 psig PRV; T&P gauge (field-installed on supply); pre-wired and internally piped; NG factory-set with LP conversion labels in literature set Certifications: ENERGY STAR (95% AFUE); ANSI Z21.13/CSA 4.9; ASME Section IV / CSA B51; zero-clearance to combustibles when installed per instructions Warranty: Limited lifetime heat-exchanger warranty (residential); parts coverage up to 5 years with registration—see Viessmann warranty Save Fuel With High Efficiency At 95% AFUE—and up to 98% efficiency at low return temps—the CU3A-160 squeezes more heat out of every therm, reducing monthly fuel spend while keeping comfort high. Everyday Performance You Can Feel A 43–160 MBH input range and high-mass water volume minimize short-cycling, delivering smooth, quiet heat across changing loads—great for older radiators and mixed high-temp zones. Built To Last The Inox-Crossal stainless heat exchanger and MatriX burner are engineered for clean combustion and self-shedding condensate, helping maintain efficiency and resist corrosion over years of service. Installer-Friendly Flexibility Choose coaxial or two-pipe direct venting with long allowable runs (up to ~198 ft, layout-dependent). Standard 1¼" supply/return and ¾" gas connections simplify piping and commissioning. Smart Controls & Compatibility On-board Vitotronic outdoor-reset control supports multi-circuit designs and easy setup, so systems start quickly and run efficiently in day-to-day operation. Fits Your Space Compact footprint and a listing for zero-clearance to combustibles enable closet or alcove installs while keeping full front/rear service access.