CareHomeDeskCareHomeDeskTMVs must be maintained and tested annually -- or more frequently where manufacturer guidance or the water risk assessment specifies. The test must confirm the valve is blending correctly and the temperature at the outlet does not exceed 44C for care home use.
Thermostatic mixing valves blend hot water stored at 60C or above -- the temperature needed to control Legionella -- with cold water to deliver a safe temperature at the outlet, protecting residents from scalding. Many care home residents have reduced mobility, sensation or cognitive awareness and cannot react quickly to water that is too hot, which is why TMVs (often to the TMV3 healthcare specification) are fitted at baths, showers and basins used by residents.
TMVs must be serviced and tested at least annually, in line with manufacturer guidance and the site's water risk assessment, though some manufacturers or higher-risk situations call for more frequent checks such as every six months. The annual test must confirm the valve is blending correctly across its operating range and that the temperature delivered at the outlet does not exceed the maximum set for care home use, commonly 44C, and does not fail in a way that could deliver unmixed hot water.
A compliant TMV record shows the outlet identified, the date of test, the measured outlet temperature, confirmation the valve was dismantled, cleaned and inspected internally where the servicing regime requires it, and the name of the competent person who carried out the work. A record that only states "TMV checked, pass" without a temperature figure does not meet the standard expected and would not withstand scrutiny during an inspection.
A TMV that has drifted out of calibration or failed creates two risks simultaneously rather than a single issue: if it fails toward delivering hotter water, residents are exposed to scalding risk; if it fails toward delivering cooler water, or if cold-side temperatures have risen due to a system fault, conditions become more favourable for Legionella growth at the outlet. This dual exposure is why TMV maintenance sits at the intersection of water hygiene and general health and safety compliance.
CQC inspection reports have increasingly flagged TMV maintenance as a specific area of concern, typically where annual servicing has lapsed, where records exist but show no temperature readings, or where a valve identified as due for service has continued in use past its due date without any documented risk assessment justifying the delay. Building a fixed annual servicing contract with a competent engineer, rather than relying on ad hoc call-outs, is the most reliable way to avoid these findings.
CareHomeDesk gives you compliance checklists, maintenance logs, and contractor management tools built around exactly this kind of knowledge.