A. O. Smith · Voltex MAX / Signature 900 Premium (HPTA, HPA10)
A. O. Smith Voltex MAX / Signature 900 Premium (HPTA, HPA10) error code 048
Battery low energy
What it means
Battery Low Energy.
How it shows: with an alert icon flashing (also flashing red LED)
What A. O. Smith says to do
1. Make sure the battery protective tab has been properly removed from the battery tray, located on the left side of the Control Assembly. 2. Locate the battery tray on the side of the Control Assembly. 3. Remove the Phillips head screw, slide the battery tray out from the Control Assembly. 4. Remove the old battery and replace with Panasonic BR2032 or Murata CR2032 battery only. Use of another battery may present a risk of fire or explosion. 5. Reinstall the battery tray with new battery and hand tighten the Phillips head screw. NOTICE: If the Control Assembly was not connected via Wi-Fi, Bluetooth, or powered by a power source, the time will need to be set.
The manual adds: "These instructions are brief and intended as guidance for a qualified person. If you lack the necessary skills to perform these procedures call the Technical Assistance Hotline which is listed on the water heater's warranty sheet for assistance." (Hybrid Electric Heat Pump Water Heater Installation Instructions and Use & Care Guide (Premium/Smart Valve), 100379654_2000812401, page 27)
Last checked 2026-10-03.
Safety first
- WARNING! Working near an energized circuit can result in severe injury or death from electrical shock. (p.28)
- WARNING! When you are finished, be sure all covers are secured to reduce the risk of fire and electric shock. (p.28)
From the manufacturer's manual for this series.
The same code on other models
Codes mean different things on different heaters. Match the series to the model number on your rating label.
- A. O. Smith Voltex AL Smart / Signature 900 Standard (HPTS, HPS10): 048
- A. O. Smith Voltex 120V plug-in (HPTV, HPV10): 048
Other Voltex MAX / Signature 900 Premium (HPTA, HPA10) codes
- 001 (Dry-fire)
- 003 (Upper thermistor sensor failure)
- 004 (Lower thermistor sensor failure)
- 006 (Internal Processor Error)
- 009 (Power supply voltage too low)
- 021 (Upper element circuit failure)
- 022 (Lower element circuit failure)
- 025 (Heat pump coil temperature sensor)
- 026 (Heat pump suction temperature sensor)
- 027 (Heat pump discharge temperature sensor)
- 028 (Ambient temperature sensor failure)
- 029 (Outlet temperature sensor failure)
- 031 (Water leak)
- 044 (SAC anode depleted)
- 046 (Shut-off valve)
- 047 (Smart Valve failure)
- 080 (Air filter dirty)
- 081 (Condensate management)
- 083 (Compressor suction pressure too low)
- 084 (Compressor not functioning)
- 085 (Compressor discharge temperature too high)
- 086 (Fan speed feedback)
- HPO (Heat pump out of operating range)
- ICE (Heat pump defrost)
- CLR (Error code cleared)