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Slant/Fin · Error codes

Slant/Fin Lockout 85 — Inlet/outlet Inversion Limit

Lockout 85

LockoutSlant/Fin CHS condensing fire-tube boilers (lockout/hold/alert codes)

Inlet/Outlet Inversion Limit. Possible cause: pump flowing in the wrong direction. Corrective action: ensure water circulation through the boiler is in the correct direction, see Figure 10-1. The table classifies it as Lockout.

Applies to

This fault code is displayed by the CHS control (Sola) on CHS models (CHS-85 through CHS-399), as documented in Slant/Fin CHS 85-399 Installation and Operation Manual, 84703 (V.2018-07-11) (84703). Codes can differ between controller generations, so always check the manual that matches your unit.

Controller: CHS control (Sola). Source manual: 84703.

Why a code is not a diagnosis

The code reports the condition the control detected; the underlying cause must be confirmed on site by a licensed technician using the manufacturer's procedure.

Safe things to observe

  • Note the exact code, when it appears and what the appliance was doing.
  • If the appliance has stopped, call a technician rather than repeatedly restarting it.
  • If you smell gas, stop, go outside and call your gas utility's emergency line or 911 before anything else.

Do not

  • Do not ignore a code that returns after a reset.

How professional service helps

  1. A licensed technician diagnoses the cause with the manufacturer's test procedure.
  2. Combustion and safety devices are verified with an analyser and the manufacturer's procedure after any repair.

Where ROMA provides on-site service

On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.

See all service areas

Frequently asked questions

Can I clear this code myself?

Clearing a code without fixing its cause usually just brings it back. Note the code, check the safe items on this page, then call a licensed technician. If your appliance manual describes a user reset for this exact code and it stays away, no call may be needed.

Boiler locked out? Call with the alert text ready.

The brand, model and this alert are passed along when you request service online, so the technician arrives prepared.

On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.

Sources and verification

Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.

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