HVACopediaGlow Brand · Boiler
tESt System test active
What the display is showing
The installer system test is running; the small digits alternate between tESt and the active test (FAN, Lo, Ign, Hi, REg, Stb, LCO1). The boiler is locked in CH mode and needs a heat load.
Applies to: B85, B120, B160 (NG and LP)
Settings for these units
Maintenance intervals · Glow B85/B120/B160
| Item | When |
|---|---|
| Annual inspection by a technician | Every year (warranty) |
| Relief valve try-lever test | Annually |
| LWCO test | Annually |
| Condensate trap clean | Annually (14.3) |
| Heat exchanger combustion-side wash | Annually or when combustion drifts (14.4) |
| Burner door silicone gasket | Replace if damaged or after 2 years |
| Service reminder | 2.203 on, interval 2.204 (default 1000 days) |
Operating pressure should sit 5 psi under the relief valve rating (max 25 psig on a 30 psi valve); water never above 180 F.
Models that show this code
3 models in Glow B85/B120/B160
Other codes on the same units
- Loc 4 Blocking error lasted over 20 hours
- Loc 5 Fan not running for more than 60 seconds
- Loc 6 Fan running too slow for more than 60 seconds
- Loc 7 Fan running too fast for more than 60 seconds
- Loc 8 Internal software fault
- Loc 9 EEPROM contents out of date
- dAir De-air sequence running
- init Display starting up
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Source: Glow Brand B85/B120/B160 Installation & Operation Manual V20231025, 11.10 p.60. Summarized in our own words; check the original manual for your model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.