Radiant Floor Not Heating? Diagnosis Guide for Metro Vancouver
Radiant floor heating systems provide comfortable, energy-efficient heat, but when they stop working properly, diagnosis can be more challenging than with traditional radiators. In-floor heating systems have components that are often concealed beneath flooring or in access panels, making it harder to identify the source of the problem. CANRO Heating and Cooling has extensive experience diagnosing and repairing radiant floor heating systems in Metro Vancouver homes.
Common Causes of Radiant Floor Heating Failure
Radiant floor heating systems can fail for several reasons, and identifying the correct cause requires systematic investigation. The most common causes include a failed circulator pump, air locked loops, manifold valve issues, thermostat problems, and boiler-related faults if the radiant floor is part of a hydronic system. If the entire radiant floor system is cold, the issue is likely with the boiler, primary pump, or system controls. If only certain zones or loops are cold while others work, the problem is likely in the manifold, zone valve, or individual loop. A sudden complete failure often indicates a pump or electrical issue, while gradual loss of heat over time suggests sludge buildup or a developing pump problem.
Checking Your Radiant Floor System Controls
Start by verifying the basics. Ensure the thermostat controlling the radiant floor zone is set to heat mode with the temperature set above room temperature. Check whether the thermostat has power and the display is functional. If the thermostat uses batteries, replace them even if the display is working, as weak batteries can cause intermittent operation. Check the manifold station, usually located in a mechanical room or utility closet. Verify that the flow meters or indicator pins show water flowing through each loop. Look at the manifold pump to see if it is running. Listen for the sound of the pump operating and feel the pump body for vibration or heat, which indicates it is running. If the pump is warm but not running, it may have seized or failed.
Air Locks and System Pressurization
Air locks are a common problem in radiant floor systems, especially after the system has been serviced or if there has been a loss of system pressure. Air trapped in the loops prevents proper water circulation, causing cold spots or complete loss of heat in the affected zones. Air in radiant floor systems can be difficult to bleed because the loops are often long with multiple high points where air can accumulate. If you suspect an air lock, try running the system with the manifold air bleeder valves open to allow trapped air to escape. Check the system pressure gauge, it should typically read 12 to 15 psi when the system is cold. If the pressure is low, add water through the fill valve to bring it up to the correct range. If your system loses pressure repeatedly, there is likely a leak that needs to be located and repaired.
When CANRO Can Help with Radiant Floor Issues
CANRO Heating and Cooling provides comprehensive diagnostic and repair services for radiant floor heating systems throughout Metro Vancouver. Our technicians are experienced with all types of in-floor systems including staple-up, slab-on-grade, and above-floor installations. We carry replacement circulator pumps, manifold components, thermostats, and zone valves for most major systems. If your radiant floor system requires more extensive diagnosis, our technicians have thermal imaging cameras to identify cold loops, flow meters to measure circulation rates, and the expertise to perform power flushing if sludge buildup is restricting flow through the loops. Call (604) 559-1612 to schedule service.
Safety Reminder
If you smell gas, suspect carbon monoxide or believe there is an immediate danger, leave the property and contact emergency services or the appropriate gas emergency authority. Do not remain inside — exit the building immediately and call for help from outside.