SolarpunkHomes
Sign inCall us · +44 7510 081687
Solar
Solar · Error codes · SolaX Power
BMS_TemLowSolaX Power

BMS_TemLow on a SolaX Power battery: Low temperature of BMS. Solution: Warm up BMS and restart; contact after-sales

Short answer

On a SolaX Power battery, BMS_TemLow means: Low temperature of BMS. Solution: Warm up BMS and restart; contact after-sales. The battery stops until the fault clears or is reset. The wording differs by model range — each is shown below.

Reviewed 24 September 2026 · 2 sources

What it means

On the Triple Power T Bat Hv S

The manual says: Low temperature of BMS. Solution: Warm up BMS and restart; contact after-sales.

Part involved: T-BAT SYS-HV BMS.

On the SolaX X1-Hybrid G3

The manual says: Battery Fault - under-temperature fault.

Part involved: Battery voltage / state of charge.

Likely causes:

  • As described in manual.

Is it safe?

On the Triple Power T Bat Hv S

Does the battery stop?Yes
SeverityFault — clears by itself when the condition goes

The battery stops until the fault clears or is reset.

Resetting itself: after temperature normalises and restart.

Manual reset: Restart BMS (installer-guided).

On the SolaX X1-Hybrid G3

Does the battery stop?Partly
SeverityWarning

The battery keeps running with some functions stopped.

Resetting itself: usually - clears once the battery recharges from PV or grid.

Manual reset: sometimes (battery activation/force charge).

What you can check

On the Triple Power T Bat Hv S

  • Read and note the exact code or light pattern and the time (photo or app screenshot).
  • Look (without opening anything) that nothing is blocking the unit's vents, it is not in direct sun and the space around it is not unusually hot or cold.
  • Wait for the battery to return to normal temperature - it can then restart.
  • Check the battery/inverter AC isolator and the consumer-unit breaker are ON. Do not keep resetting a breaker that trips again straight away.
  • Never open the battery, inverter or gateway casing and never touch DC cables, connectors or battery terminals.
  • If the code stays or keeps coming back, contact your installer (quote the code) - do not keep power-cycling.

On the SolaX X1-Hybrid G3

  • Read and note the exact code and time from the inverter display or app (screenshot).
  • Check the battery is switched on and not paused in the app.
  • Check reserve/charge settings in the app; in cold weather charging may pause below 0 C.
  • Where the SolaX manual says 'press the ESC key to restart the inverter', a homeowner can do that on the display. Steps that say 'disconnect PV+/PV-/battery' are for the installer only.

What the engineer will check

On the Triple Power T Bat Hv S

  • Restart BMS via POWER button/switch sequence; check BMS-inverter CAN cable and series box; check module firmware/type match; contact SolaX after-sales.

Who to ask for: battery storage installer.

Certification: SolaX-trained installer ('skilled worker' per manual); MCS battery certification.

On the SolaX X1-Hybrid G3

  • Measure battery voltage.
  • Force-charge / battery activation per manual.
  • Check BMS alarms and cell imbalance.
  • Check DC breaker and polarity.

Who to ask for: Battery installer.

Certification: Electrician competent in electrical energy storage (BS 7671 Chapter 57; IET Code of Practice for Electrical Energy Storage Systems), ideally the MCS battery installer (MIS 3012); brand-approved installer to keep warranty.

What you might notice

Sources

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 24 September 2026