Fox ESS products are designed for safe and reliable operation across a wide range of real-world installation environments. Published installation manuals provide recommended clearances and environmental conditions based on standardised testing and optimal performance scenarios.
Download a PDF copy of this statement.
We recognise that, due to the nature of UK properties and installation constraints, these recommendations cannot always be strictly achieved. This statement provides clarification on acceptable deviations.
General Principle
Where installation conditions differ from those stated in the product manual:
- Installations may deviate from recommended clearances, provided that:
- Adequate airflow and heat dissipation is maintained
- Equipment remains accessible for service and isolation
- Installation complies with BS 7671, MCS requirements, and all relevant local regulations
- The installing contractor retains responsibility for:
- Site-specific design decisions
- Ensuring thermal performance and safety are not compromised
- Documenting justification for any deviation
Deviation from recommended clearances does not automatically invalidate product warranty, provided the above conditions are satisfied.
Outdoor Installations
For outdoor installations:
- Fox ESS equipment is designed for external use in line with its IP rating (typically IP65/66)
- Reduced clearances are generally acceptable due to:
- Natural ventilation
- Lower risk of heat accumulation
Batteries:
- Reduced clearances may be applied on all sides where:
- There is no obstruction to natural airflow
- The installation does not create a confined or sealed space
Inverters:
- Side and lower clearances may be reduced where necessary
- A reasonable clearance above the inverter should be maintained to allow heat dissipation
- Installations must avoid enclosed or heat-trapping configurations
Indoor Installations
For indoor installations:
- Greater adherence to manual clearances is recommended due to reduced natural airflow
- Where significantly reduced clearances are proposed:
- These should be assessed case-by-case
- Consideration must be given to:
- Room volume and ventilation
- Ambient temperature
- Heat build-up over sustained operation
Where uncertainty exists, consultation with Fox ESS technical support is advised.
Installation Within Enclosures
Installation within enclosures or cupboards is acceptable where:
- The enclosure is not airtight and allows sufficient ventilation
- Heat build-up is mitigated through:
- Passive airflow (vents/louvres), or
- Active ventilation where required
- Safe access for operation, maintenance, and isolation is maintained
Installers must ensure that the enclosure design does not adversely affect thermal performance or safety.
Environmental Exposure
- Products rated for outdoor use (e.g. IP65) may be installed in exposed environments
- However, best practice is to:
- Avoid prolonged direct solar gain where possible
- Prevent standing water, snow accumulation, or debris build-up
- The use of a canopy or shading is not mandatory, provided the installation remains within operating temperature limits
Compliance & Warranty
- Installations must comply with:
- BS 7671 (IET Wiring Regulations)
- MCS requirements (where applicable)
- Any other relevant UK standards or DNO requirements
- Where deviations from manuals occur:
- Installers must record justification as part of system design and handover documentation
Fox ESS confirms that reasonable deviations from published clearances, when implemented in line with this guidance, do not in themselves invalidate product warranty.
Further Guidance
This statement is intended to support practical installation scenarios. Where installations fall significantly outside typical conditions, or where there is uncertainty, installers should seek project-specific guidance from Fox ESS technical support.
Note on Cabling
Cabling requirements (including CPC sizing and conductor types) are governed by applicable standards and should be assessed separately in accordance with BS 7671. Manufacturer recommendations should be followed unless an engineered alternative is justified and compliant.
