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Heat pumps · Error codes · Cool Energy
Er14Cool Energy

Er14 on a Cool Energy heat pump: Water tank temperature sensor fault

Short answer

On a Cool Energy heat pump, Er14 means: Water tank temperature sensor fault. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.

Reviewed 23 September 2026 · 2 sources

What it means

On the ecoTech DC Inverter (R32 EVI)

The manual says: Water tank temperature sensor fault.

On the Inverter range CE-iH (R410A, c.2020)

The manual says: Water flow protection.

Is it safe?

Does the heat pump stop?Yes
Engineer needed?Yes

The heat pump stops until the fault clears or is reset.

What you can check

On the ecoTech DC Inverter (R32 EVI)

  • Read and note the code shown on the controller display, then contact your installer or service engineer.

On the Inverter range CE-iH (R410A, c.2020)

  • Read and note the code shown on the controller display, then contact your installer or service engineer.
  • Check the heating system pressure gauge reading against the value in your handover documents (manufacturer commissioning values: typically 1-2 bar) and that the filling loop is closed.

What the engineer will check

On the ecoTech DC Inverter (R32 EVI)

  • Check the named sensor/probe connection at the PCB (loose/oxidised plug).
  • Measure sensor resistance against the manufacturer table and replace if faulty.
  • Check controller/PCB if sensor is good.

Who to ask for: heat pump controls / electrical.

Certification: Electrical competence.

On the Inverter range CE-iH (R410A, c.2020)

  • Check water flow rate/flow switch and wiring.
  • Check strainer/magnetic filter for blockage.
  • Vent air from the system.
  • Check circulating pump operation and pipe sizing.
  • Check valves/zone valves are open.

Who to ask for: heating / plumbing heat pump installer.

Certification: None specific (unvented/G3 if cylinder work).

What you might notice

Sources

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 23 September 2026