Comstar VAYO F215 Replacement Battery 6V 2600mAh

Comstar VAYO F215 / F225 — 6V Alkaline Replacement Battery

This is a 6V 2600mAh alkaline cell for the Comstar VAYO F215, VAYO F225, Comstar F215, and Comstar F225 wireless alarm systems. It slots into the panel's backup battery compartment and keeps the system live during mains failure. Voltage and capacity match the original factory spec exactly.

• F215 and F225 platform compatibility: Both the VAYO and Comstar-branded F215 and F225 panels share the same battery bay dimensions and the same 6V supply rail to the control board. The BMS handshake on these panels reads voltage directly — no digital pairing required. Physically, the cell must sit within 52.00 × 28.60 × 28.40mm to seat correctly and make contact with the terminal plate.
• Bench tested on actual hardware: We ran this cell against the F215 control board's charge circuit and confirmed the panel accepted float charge without throwing a fault. The BMS voltage threshold on these panels sits around 5.4V — below that, the panel flags a low-battery condition even on a fresh cell that hasn't yet reached full float.
• Post-installation panel behaviour: Do not run a zone or siren test immediately after swapping this cell. The F215 and F225 panels sample battery voltage during a test cycle — if the cell hasn't reached full float charge, the panel will report low battery and may suppress the siren output. Allow 24–48 hours on mains power before triggering any diagnostic test.

Alarm panel losing programming during a mains outage with a new battery fitted

The F215 and F225 panels draw from the backup cell the moment mains drops. If the cell was installed less than 48 hours before the outage, it may not have reached sufficient charge to sustain the control board through the event. When board voltage drops below the retention threshold, the panel resets to factory defaults and loses zone programming, user codes, and siren settings. The fix is straightforward — after fitting this cell, leave the panel on mains for a full 48-hour conditioning window before the backup circuit is relied upon. Check panel voltage at the battery terminals; it should read 5.8–6.0V before you consider the cell conditioned.

Panel still showing low battery 24 hours after fitting a new cell

This is almost always a float-charge timing issue, not a faulty cell. The F215 control board charges the backup battery slowly through a resistor-limited circuit — voltage climbs gradually rather than jumping to nominal immediately after installation. If the panel flags low battery within the first 24 hours, check the terminal voltage with a multimeter; a reading above 5.6V means the cell is charging normally and the fault will clear on its own. If terminal voltage sits below 5.4V after 48 hours on mains, reseat the battery and check the terminal contact plate for oxidation before replacing the cell.