Generac — Check Battery Condition and Fluid Level
Maintenance · Battery System
From a Generac owner's manual — check it applies to your exact model before use.
Applies to: Generac 15 kW EcoGen, Generac GT-999 engine
Before you start
- Always disconnect negative battery cable first.
- Always connect positive battery cable first during installation.
- Sparks may cause battery explosion if positive contacts ground with negative installed.
Parts for this job
- 0H3421S Battery Amazon eBay $283.32
Part numbers from the service-parts list for Generac 15 kW EcoGen. Verify against your serial number before ordering; some links are affiliate links.
Procedure
- Verify battery condition by visual inspection.
- Clean battery and terminals if necessary.
- Check fluid level in unsealed batteries only.
- Fill with distilled water only if necessary. Do not use tap water.
- Check state of charge using digital multimeter.
- Recharge and retest if state of charge below manufacturer recommendations.
- Replace battery if unable to hold charge or if damaged.
Tools required
- Digital multimeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Battery type: Group 26R
- Battery voltage: 12 Volts
- Battery CCA minimum: 525 CCA
- Battery part number: 0H3421S Amazon eBay $283.32
- Check interval: 500 hours or 2 years
Full service-parts list: Generac 15 kW EcoGen →
Source: Generac owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.