IBC Technologies · Error codes
IBC VX “Summer” display message
Summer
The manual lists this warning when a thermostat call for space heating arrives but the outdoor temperature is above the Summer Shutdown temperature set for that load, so the boiler will not fire for heating. It applies to space-heating loads, not to domestic hot water.
Applies to
This warning message is shown by the V-10 touchscreen controller on VX Series residential boilers (VX 110, VX 150 and VX 199), as documented in IBC Installation & Operating Manual — VX 110 / VX 150 / VX 199, doc 120-347E6, sections 9.2–9.4.
Controller: V-10 touchscreen controller. Source manual: 120-347E6 (2026-08-07).
Why a code is not a diagnosis
The warning is a logic message, not a fault: the outdoor sensor says it is warm enough that heating should stay off. If rooms are actually cold while this shows, the outdoor sensor reading or its mounting (the manual specifies a north-facing position out of direct sunlight) may be wrong.
Safe things to observe
- Check the outdoor temperature the boiler is reading versus the real temperature outside.
- If you want heating in warm weather (for example to dry a basement), the Summer Shutdown setting can be adjusted by someone who knows the controller.
- If hot water is the issue, this warning does not apply to DHW calls.
Do not
- Do not move or shade the outdoor sensor yourself without knowing its purpose.
How professional service helps
- A technician verifies the outdoor sensor reading and mounting, and adjusts the Summer Shutdown temperature if the occupants want heating above it.
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.
Parts and service
Parts commonly involved
These parts appear in the documented text for this alert. A code reports a condition, not a failed part — a technician confirms the cause by testing before anything is replaced.
Room thermostat
The room thermostat is the switch that tells a heating zone to call for heat, and on a modern boiler it is also part of the control system's wiring.
What a technician checks →
Service for this alert
- Gas Boiler Repair
Licensed gas technicians from ROMA Heating & Cooling diagnose and repair residential and light-commercial gas boilers across…
Every boiler part explained — what it does, how it fails and what a technician checks.
Documented for IBC Technologies VX Series.
Frequently asked questions
Why won't my boiler heat when it says Summer?
Because the controller thinks it is warm enough outside that heating is not needed. Check the outdoor temperature reading; if it is wrong, the sensor needs attention.
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
- IBC Installation & Operating Manual — VX 110 / VX 150 / VX 199, doc 120-347E6, sections 9.2–9.4 · 120-347E6 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.