What Colorado's New Furnace Rules Mean for Your Home

---

Colorado changed its rules for gas furnaces starting January 1, 2026. If your furnace needs to be replaced, here is what you need to know.

What is NOx and why does it matter?

NOx stands for nitrogen oxides. These are gases that come out of your furnace when it burns natural gas. You cannot see them, but they contribute to smog and make the air harder to breathe -- especially along the Front Range.

A Low NOx furnace is simply a furnace that releases less of those gases. It burns cleaner. The air outside your home is better for it.

What changed?

Colorado now requires all new furnace installations to meet Low NOx standards. Standard 80% efficiency furnaces no longer qualify in most cases. Two options still pass:

1. A high-efficiency furnace rated 95% or higher -- this is the right choice for most homes
2. A specialty 80% furnace built with ultra-low NOx burners -- less common, not available from every brand

Most homeowners will go with option one. A 95%+ furnace is easy to find and can lower your gas bill too.

Do you have to switch to electric?

No. Gas furnaces are still allowed. The law does require that your new system be installed in a way that could support a possible future upgrade to electric heat -- like a heat pump -- if you ever want one. For most homes, this means nothing changes. Older homes may need a small electrical update, like a dedicated circuit or panel check. We will tell you upfront if yours does.

Sanchez Mechanical is fully compliant.

We have compliant Trane units available now, including:

• Trane L8V1 -- 80% AFUE, variable speed, ultra-low NOx certified
• Trane S9V2 -- 90% AFUE, high-efficiency, meets all new Colorado standards

You will not have to wait, and you will not be steered toward equipment that does not fit your home. We will walk you through your options and give you a straight answer on cost.

Download the Trane Ultra-Low NOx Furnace Spec Sheet (PDF)

What should you do next?

If your furnace is getting old or giving you trouble, do not wait until it quits in January. Call us now. We will walk you through your options and give you a straight answer on cost.

Contact Sanchez Mechanical Call 303-287-9084