Mitsubishi H2i vs Bosch IDS Ultra vs Carrier 37MUH: Which Cold Climate Heat Pump?

All three work in Colorado winters. The right choice depends on your home:

• Mitsubishi H2i - Best for fully electric ducted homes up to roughly 2,500 sq ft
• Bosch IDS Ultra - Best all-arounder for ducted retrofits with flexible configuration options
• Carrier 37MUH - Solid mid-range option with proven cold-climate performance

We've installed over 4,600 of these three systems combined. Here's what we've learned about when each one makes sense.

The Mitsubishi H2i is what put cold-climate heat pumps on the map. We've installed over 4,000 of these systems in Colorado, and they have our lowest callback rate of any equipment we carry.

Why It Works

Mitsubishi pioneered flash injection compressor technology with the H2i line. This isn't marketing spin. It's a fundamentally different compressor design that maintains heating capacity when temperatures drop.

• 100% heating capacity down to 5 degrees F - Most "cold climate" units start losing capacity around 17 degrees F
• Continues operating to -24 degrees F - Even during our worst cold snaps, it keeps running
• Up to 30.5 SEER cooling efficiency - Outstanding summer performance too

Best Applications

• Your home is under roughly 2,500 sq ft and you want fully electric heating (no gas backup)
• You don't have existing ductwork and want to avoid the $10,000-$20,000 cost of adding it
• You want zoned comfort with different temperatures in different rooms
• You're adding heating/cooling to a basement, addition, or garage conversion

Configuration Options

• Wall-mounted units - Most common, visible but quiet
• Ceiling cassettes - Flush-mount in ceiling, more discreet
• Floor-mounted units - Good for rooms with limited wall space
• Ducted air handlers - Connects to existing or new ductwork

Typical Cost

A 4-zone Mitsubishi H2i system for a 2,400 sq ft home runs approximately $29,000-$32,000 before rebates. After Xcel Energy, state, and HEAR rebates (if eligible), out-of-pocket can drop to $10,000-$16,000.

The Bosch IDS Ultra is our go-to recommendation for homes with existing ductwork. We've installed over 600 of these systems, and the flexibility makes them ideal for retrofits.

Why It Works

Bosch engineered the IDS Ultra specifically for cold climates with an Enhanced Vapor Injection (EVI) compressor. The variable-speed inverter modulates in 1% increments, meaning it precisely matches your heating needs rather than cycling on and off.

• 100% heating capacity at 5 degrees F - Holds strong through most Colorado winter nights
• Continues operating to -13 degrees F - Covers our coldest temperatures
• R-454B refrigerant - Already compliant with 2026 regulations, future-proofed

Configuration Flexibility

This is where Bosch really differentiates. The IDS Ultra works with:

• Air handler configuration - Heat pump outdoor unit + electric air handler. Fully electric, no gas needed.
• Furnace + coil configuration - Heat pump outdoor unit + your existing or new gas furnace + evaporator coil. Dual-fuel setup for extreme cold backup.
• Coil-only configuration - Heat pump outdoor unit + evaporator coil only. Works with existing compatible air handlers.

Typical Cost

A Bosch IDS Ultra system for dual-fuel (heat pump + furnace) runs approximately $25,000-$28,000 before rebates. After rebates, out-of-pocket can drop to $8,000-$16,000 depending on your rebate eligibility.

The Carrier 37MUH is a crossover cold-climate heat pump used for ducted systems, delivering solid performance at a more accessible price point. We've installed about 80 of these systems with good results.

Why It Works

The 37MUH is manufactured by Midea, one of the world's largest HVAC manufacturers, and sold under the Carrier name. Some customers ask about this. Here's our take: it performs great. The track record speaks for itself. Carrier has a strict quality control process for the 37MUH, and it has a good track record in Colorado.

• Operates down to -22 degrees F - Solid cold-climate capability
• Up to 22 SEER cooling - Efficient summer performance
• Variable-speed inverter compressor - Quiet, efficient operation

Compared to Mitsubishi H2i

Bottom line: If budget allows, Mitsubishi H2i is the superior ductless option. For ducted systems, if you need to balance cost and performance, the 37MUH delivers.

Answer a few questions to see which system fits your situation best:

We focus on these three because they're the cold-climate heat pumps we trust in Colorado winters. We've tested other brands and found issues:

• Daikin - Capacity issues and reliability problems in our climate
• Lennox - Frequent compressor failures
• Trane (new R454B models) - Too new, early experience not promising
• MrCool - DIY units not designed for real cold-climate performance
• Rheem - Breaks often, can't keep up in our climate
• Fujitsu multi-zone - Single-zone OK, multi-zone struggles

All three systems qualify for the same rebates:

Not sure which system fits your home? Here's what happens when you contact us:

1. We assess your home - Square footage, existing HVAC, ductwork condition, electrical capacity
2. We recommend options - Usually 2-3 system configurations with pros/cons for your situation
3. We show you real numbers - Equipment cost, installation cost, all applicable rebates calculated
4. You decide - No pressure, take your time

We've installed over 12,000 heat pumps across the Denver metro. We'll tell you which system makes sense, even if that means recommending something we don't install.