58 Boiler Fault Code: What It Means on Every Brand

The 58 fault code appears on 2 brands — Nibe and Viessmann — and it does not mean the same thing on each. The same two or three characters can signal a pressure problem on one boiler and an ignition fault on another, so identify your brand first and use the table below to jump to the right page.

Up to: Lockout — engineer likely 2 brands use this code Meaning differs by brand

Which brand is your boiler?

The brand is printed on the front casing. Tap your brand for the full causes, fixes and repair costs.

Brand	What 58 means	Severity	DIY?
NNibe	Fault code 58 on Nibe heat pumps indicates that a pressure switch has tripped — either on the high-pressure or low-pressure side of the refrigerant circuit. Full guide →	Lockout — engineer likely	Some checks
VViessmann	Fault code 58 on a Viessmann boiler indicates that the control unit has detected an open-circuit or complete loss of signal from the domestic hot water (DHW) temperature sensor. Full guide →	Engineer may be needed	No

58 brand by brand

Nibe 58

Fault code 58 on Nibe heat pumps indicates that a pressure switch has tripped — either on the high-pressure or low-pressure side of the refrigerant circuit. When this alarm triggers, the compressor is immediately blocked and the heat pump stops producing heat or hot water. On most Nibe models the system will not restart automatically; the alarm must be manually cleared via the controller display once the underlying issue has been addressed. Repeatedly resetting without investigating the root cause risks damaging the compressor.

Causes, fixes & costs for Nibe 58 → · All Nibe codes

Viessmann 58

Fault code 58 on a Viessmann boiler indicates that the control unit has detected an open-circuit or complete loss of signal from the domestic hot water (DHW) temperature sensor. In practical terms, the boiler's electronics can no longer read a valid temperature from the DHW circuit, so as a precaution the boiler stops producing hot water — though space heating typically continues to work normally. The fault points specifically to an interruption (open circuit) in the sensor circuit, distinguishing it from related codes: code 50 signals a short circuit on the DHW cylinder sensor, code 51 a short circuit on a related sensor, and code 59 an interruption on the ACM outlet sensor. If your display shows 58, the open-circuit fault is specifically on the DHW temperature sensor itself or its wiring. Codes 50, 51, 58, and 59 are among the more frequently seen Viessmann error codes and all share the same headline symptom — no hot water but central heating still operating.

Causes, fixes & costs for Viessmann 58 → · All Viessmann codes

Frequently asked questions

Is the 58 fault code the same on every boiler?

No. 58 means different things on different brands — see the table above. Always identify your boiler's brand (it is printed on the front casing) before acting on any advice about the code.

Can I fix a 58 fault myself?

On some brands there are safe homeowner checks first — typically system pressure, the condensate pipe in cold weather, and a single reset. Where the code is a simple pressure or reset condition, that may be all it needs. Never open the boiler casing yourself.

Who should I call about a 58 fault?

For gas boilers, a Gas Safe registered engineer — it is a legal requirement for any work on the appliance. For heat pumps, an MCS or F-Gas qualified heat pump engineer. If you smell gas at any point, leave the property and call the National Gas Emergency line on 0800 111 999.

General guidance only — not a substitute for professional advice, and not certified by a registered engineer. Any work on a gas appliance must be carried out by a Gas Safe registered engineer. If you smell gas, call 0800 111 999.