Platform & Control Notes
HTP uses two schemes: wall-hung Elite FT / EFTC show 'Fxx' plus a text label; UFT/UFTC combi show 'Er:xx'. Confirm which family your unit is.
Model Families & Platforms
- Elite FT & EFTC (Wall-hung fire-tube condensing)
- UFT & UFTC (Universal fire-tube combi)
Diagnostic Characteristics & Common Service Topics
HTP boilers utilize specific display codes and safety lockouts to protect the heat exchanger, combustion system, and hydronic loop. Everyday issues like pressure loss, flame sensing errors, or circulator faults trigger specific responses depending on the controller generation.
| Code | Meaning | Action Required |
|---|---|---|
| Er:11 / F09 (No flame on ignition) | Ignition failure — failed to light after the max tries (5 on UFT, 4 on Elite FT) and locked out. | Verify the gas valve is open; one reset is OK. Don't keep resetting — a tech should check gas pressure, clean/re-gap the electrode, and inspect venting. |
| Er:10 / F10 (Flame loss) | Flame loss — boiler lit, then lost flame repeatedly during firing. | Confirm gas is on and try one reset. If it returns, stop and call a pro to check gas pressure, the flame sensor, and the flue/condensate line. |
| F11 (False flame signal) | Elite FT: control detects flame when the boiler isn't supposed to be firing. | Call a pro immediately. Gas-safety fault — a leaking gas valve must be diagnosed and replaced by a qualified technician. |
| F00 (Water high temp) | Elite FT: boiler water overheated; hard safety lockout. Pump runs to cool down. | Safety lockout — call a pro to find why it overheated (flow, pump, sensor). Don't bypass the high-limit. |
| F01 (Flue temp / water level) | Elite FT: flue temperature limit tripped OR low water level (if a low-water cutoff is installed). Hard lockout. | Flue/combustion and low-water safeties = call a pro to clear the fault and correct the root cause before resetting. |
| Er:16 (Overheat) | UFT/UFTC: operating sensor detects water above 203°F (95°C). | Self-clears as water cools (pump runs to cool the boiler). If it recurs, call a pro to check flow and sensors. |
| F02 / F03 (Supply / return sensor) | Elite FT: supply (F02) or return (F03) temperature sensor failed; lockout. | Sensor replacement is a tech task. Boiler won't restart until the sensor is replaced and RESET is pressed. |
| Er:20 (Condensate) | UFT/UFTC: condensate trap/switch open (should be closed). | Check the condensate hose is connected and not clogged/frozen. If clearing the line doesn't fix it, call a pro (vent/condensate blockage can be a flue-safety issue). |
Complete Error Code Library
For the complete searchable error-code lookup table for HTP equipment (including all 10 codes, exact lockout causes, and technician actions), visit the Phillips Hydronics Error Code Library.
Related Symptom & Diagnostic Guides
Sources & Documentation
- error-codes.json — https://www.manualslib.com/manual/1475860/Htp-Elite-Ft-Eft-285.html?page=58