Generac NP-30G / NP-40G — Drying the Generator
Maintenance · AC Generator Stator
For the Generac NP-30G / NP-40G, from the Generac service manual.
Applies to: Generac NP-30G, Generac GN-190 / GN-220 engine, Generac GN-190 or GN-220 (see NOTE 2) engine, Generac GN-220 engine
Procedure
- If insulation resistance is low, dry the winding before operating.
- Method A (heating units): enclose the generator in a covering and install heating units to raise temperature about 15-18 F (8-10 C) above ambient.
- Method B (forced air): use a portable forced air heater, directing heated air into the generator air intake openings; run the unit at no-load.
- Air temperature at point of entry into the generator should not exceed 150 F (66 C).
- Retest insulation resistance; replace the Stator if it still fails after cleaning and drying.
Tools required
- Heating units or portable forced air heater Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Heating units raise temperature about 15-18 F (8-10 C) above ambient
- Air at intake must not exceed 150 F (66 C)
Full service-parts list: Generac NP-30G →
Source: Generac service 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.