Termet MiniTerm, Ecocondens Slim E9 Error: Low or High Pressure Fault, F37/F40 Codes

User question

E 9 hibakòd esetén mi a teendő?

Artificial Intelligence Response

Direct answer to the question

• On Termet MiniTerm and many other Termet boilers, error E9 (E09) means the sealed central‑heating circuit water pressure is out of range—most commonly too low; less often too high. Restore the cold-system pressure to about 1.2–1.5 bar, then reset the boiler. If pressure is high, bleed water until ≈1.5 bar. If the error recurs, check for leaks, the expansion vessel, or a faulty pressure sensor. (termet.com.pl)
• Note: On newer Termet controllers the same pressure condition may appear as F37 (too low) or F40/F39 (too high) instead of “E9.” (files.elektroda.pl)

Detailed problem analysis

• What E9/E09 indicates
  • The controller detects CH‑loop pressure below the minimum (typically ≲0.5–0.8 bar) or above the maximum (≈≥2.5–2.7 bar) and inhibits firing to protect the heat exchanger and pump. Most field cases are a pressure drop after air purging, minor weeps, or seasonal changes; high pressure is usually overfilling or a failed expansion vessel. (naprawa.pl)
• Why it often appears after a long shutdown
  • Trapped air purges when you restart, lowering system pressure; tiny leaks may also show up after standing. (elektroda.com)
• Model‑code differences
  • Legacy Termet models use “E9/E09” for out‑of‑range water pressure, whereas recent Ecocondens families signal “F37” (low) and “F40/F39” (high). The official Ecocondens Slim manual lists F37/F40 for pressure conditions, confirming the coding shift. (files.elektroda.pl)

Current information and trends

• Termet’s official FAQ explicitly associates the “E09” communication with instructions to fill or reduce system pressure and recommends keeping cold pressure around 1.0–1.5 bar—aligning with the guidance below. (termet.com.pl)
• Newer controllers and service literature increasingly separate “low” and “high” pressure into distinct F‑codes, enabling clearer diagnostics. (files.elektroda.pl)

Supporting explanations and details

• How to fix low pressure (most common)
  1. Switch the boiler off from heating demand (standby is fine).
  2. Find the filling valve:
     • Combi units: a small black/blue knob under the boiler.
     • System/regular boilers: two valves linked by a short hose (“filling loop”) on the CH pipework.
  3. Open the valve slowly and watch the boiler display or gauge.
  4. Stop at 1.2–1.5 bar (cold), then close the valve fully. Reset the boiler if needed. (termet.com.pl)
• How to correct high pressure
  • Gently bleed a radiator or use the drain cock until the gauge reads ≈1.5 bar (cold). Termet’s FAQ also describes safe pressure reduction steps. (termet.com.pl)
• If E9/E09 returns frequently
  • Inspect for leaks at radiators and visible joints; verify the expansion vessel pre‑charge (≈0.8–1.0 bar) with the system depressurized; compare the digital reading with an external gauge to rule out a drifted pressure transducer. Forum case histories and installer notes link recurrent E9 to vessel membrane loss or a failing transducer. (poszukaj.elektroda.pl)

Ethical and legal aspects

• Gas appliances: do not open the sealed combustion chamber, disturb gas components, or bypass safeties. Charging an expansion vessel or replacing sensors should be done by a licensed/heating professional per local code. (files.elektroda.pl)

Practical guidelines

• Best practices
  • Top up slowly to avoid overshooting; recheck pressure after bleeding radiators; log pressure cold vs. hot (normal rise ≈0.3–0.5 bar). Keep cold pressure near 1.2–1.5 bar unless your installer specifies otherwise. (termet.com.pl)
• Quick triage checklist
  • Gauge <0.8 bar cold: top up to 1.3 bar → reset.
  • Gauge >2.5 bar cold: bleed down to 1.5 bar → investigate overfill/stuck fill valve.
  • Big swings (e.g., <0.8 cold to >2.5 hot): check/charge the expansion vessel; replace if water comes out of the Schrader valve. (poszukaj.elektroda.pl)

Possible disclaimers or additional notes

• “E9” is not universal: in other brands or appliance types (e.g., cooktops, dishwashers) E9 can mean very different faults. If your unit is not a Termet boiler, provide the exact make/model for device‑specific guidance. (naprawa.pl)
• On some Termet models, pressure faults present as “F37/F40” rather than E9; the remedy is the same—correct system pressure. (files.elektroda.pl)

Suggestions for further research

• Check your exact model’s user or service manual for its error table (especially if you see F‑codes). The Ecocondens Slim manual is a good example of the current coding scheme. (files.elektroda.pl)
• Termet’s “Akademia Ciepła – Komunikat E09” materials in the official FAQ offer short how‑to videos for filling/bleeding. (termet.com.pl)

Brief summary

• For Termet MiniTerm/Termet boilers, E9/E09 means CH system pressure out of range. Set cold pressure to about 1.2–1.5 bar (top up if low; bleed if high), then reset. If the error persists, look for leaks, test/charge the expansion vessel, or have a technician assess the pressure sensor. On newer Termet models, the equivalent faults are shown as F37/F40. (termet.com.pl)

If you can share the exact model (e.g., MiniTerm GCO‑DP‑21‑13, Ecocondens Slim 25, etc.) and what the gauge reads cold/hot, I can tailor the step‑by‑step to your boiler.

Disclaimer: The responses provided by artificial intelligence (language model) may be inaccurate and misleading. Elektroda is not responsible for the accuracy, reliability, or completeness of the presented information. All responses should be verified by the user.