Viessmann Vitocrossal 200 CI2‑399 | 399,000 BTU Floor‑Standing Gas Condensing Boiler
Looking for big output in a compact footprint? The Vitocrossal 200 CI2‑399 is a floor‑standing, high‑efficiency gas condensing boiler that’s easy to live with and easy to service. It modulates from 50–399 MBH (≈8:1 turndown) to match real‑world loads, and its Inox‑Crossal stainless‑steel heat exchanger helps keep efficiency high year after year.
- Brand: Viessmann
- MPN: CI2399 (Vitocrossal 200, CI2‑399)
- Type: Floor‑Standing, Category IV Condensing Gas Boiler
- Fuel: Natural Gas (LP conversion kit available)
- Input Range: 50–399 MBH
- Thermal Output (Max): 391 MBH (up to ~98% thermal efficiency, system‑dependent)
- Net AHRI (Water): 340 MBH
- Turndown Ratio: ~8:1 (series capable up to 30:1)
- Max Operating Pressure: 80 psig
- Temperature Limits: 185°F auto‑reset (max 194°F)
- Altitude: Up to 10,000 ft (electronic setting)
- NOx Emissions: < 20 ppm @ 3% O2 (NG)
- Primary Flow (Typical): ~39 GPM @ 20°F ΔT (min ~8 GPM @ 100°F ΔT)
- Venting: Direct‑vent or room‑air (per code), Category IV
- Vent/Intake Size: 4" flue collar / 4" combustion air
- Approved Vent Materials: Polypropylene (PP(s)) or AL29‑4C stainless
- Water Connections: 2" NPT (supply/return) or 2" ANSI flanges
- Gas Connection: 1‑1/2" NPT
- Electrical: 120V, 60 Hz; ~352 W max (no pumps), 17 W standby
- Controls: Integrated 7" color touchscreen with communications
- Dimensions (W × D × H): ~35‑3/4" × 29‑1/2" × 64‑1/2" cabinet
- Clearances (Service): 27" sides, 31" back, 39" front (0" to combustibles)
- Certifications: ANSI/AHRI 1500; ANSI Z21.13/CSA 4.9; SCAQMD 1146.2; BAAQMD Reg 9 Rule 6
High Efficiency, Clean Combustion
The MatriX cylinder burner and Inox‑Crossal heat‑exchange surfaces support up to ~98% thermal efficiency (with cool return temps) and low NOx (< 20 ppm) for compliant, cost‑effective operation.
Right‑Sized Modulation For Real‑World Loads
With 50–399 MBH input (≈8:1 turndown), CI2‑399 can cruise on milder spring/fall days and ramp up for design conditions—reducing cycling, improving comfort, and helping save fuel.
Compact, Retrofit‑Friendly Design
A small footprint and service‑friendly layout fit tight mechanical rooms. The cabinet is designed to move through standard doorways, making replacements and modernizations simpler in multi‑family, schools, and custom homes.
Flexible Venting & Materials
Use direct‑vent sealed combustion or draw room air per code. The boiler accepts 4" PP(s) or AL29‑4C stainless systems certified for Category IV.
Simple, Smart Controls
An integrated 7" color touchscreen speeds commissioning and diagnostics. It supports outdoor reset, DHW with storage tanks, and integration into larger systems.
