Goodman, Amana, Daikin GMVM96 error code b2
Blower horsepower mismatch
Goodman is the platform name, and your unit may not say it
Amana AMVM96 / ACVM96, Daikin GMVM96 platform are the same board with a different badge, so this page covers all of them. The fault, the checks and the parts are identical, which is why there is one page rather than one per brand.
Quick answer
On Goodman GMVM96 (2010s), b2 is a fault. It means blower horsepower mismatch. A first thing to check: Blower motor replaced with a different horsepower.
- Applies to
- Goodman GMVM96
- Goodman and Amana GMVM96, GMVM97, GCVM96 alphanumeric codes · Furnace · 2010s
- Type of code
- Fault
- Urgency: Needs attention soon
- First safe check
- Check the horsepower printed on the motor nameplate against what the model calls for.
What b2 means on this model
The control has an idea of what blower it is supposed to be talking to, and the motor on the unit does not match. In practice this is a setup problem rather than a hardware failure. It shows up after a motor swap, a control board swap, or an install mistake.
Symptoms you will notice
- Furnace runs but the blower seems to run at the wrong speed
- Code appears at start up or after a recent repair
- Blower is loud or performs poorly
Common causes
The code tells you what the control detected, not which part failed. These are the causes we see most often, roughly in order of likelihood:
- Blower motor replaced with a different horsepower
- Control board replaced and not configured to match the motor
- Motor wired incorrectly on install
- Wrong motor fitted at the factory, occasionally
What you can safely check
These are homeowner-level checks. None of them need you to open a live electrical compartment or work on gas.
- Check the horsepower printed on the motor nameplate against what the model calls for.
- If a repair was done recently, that is where to start.
Do not do these
- ×Do not change control board configuration settings without writing down what they were.
When to call a technician
Book a technician, do not keep resetting it
This fault will not clear on its own. Every power cycle gives the control one more failed attempt, and repeated attempts are what turn a cheap part replacement into a seized or contaminated system.
- This is a fuel-burning appliance, so treat anything involving a burner, gas valve or flue as technician work. If you smell gas at any point, leave the property and call the gas utility from outside rather than continuing to diagnose.
- If the appliance has stopped mid-cycle, is making a noise you have not heard before, or smells burnt, stop reading here and call. Those are symptoms of something the fault code does not describe well enough.
Reading the model spec and the motor label is fine. Board configuration and motor replacement are not.
What it costs to fix
Parts
Motor $250 to $500 if it needs replacing.
Labor
Under an hour to diagnose. Configuration is usually a matter of setting the board correctly.
DIY or technician
Reading the model spec and the motor label is fine. Board configuration and motor replacement are not.
Typical US part and labor ranges, 2026. They vary by region, model and contractor, so treat them as a planning figure, not a quote.
Scope of this code
- Code table
- Goodman and Amana GMVM96, GMVM97, GCVM96 alphanumeric codes
- Models in scope
- Goodman GMVM96, 2010s
- Checked
- Confirm on your own unit
- Find the model number on the data plate, then check this code in the service manual for that model. Manufacturers revise code tables between model years, and a revised board can renumber a fault.