CALEFFI iStop frost protection valve Operating temperature up to 90 °C

• To prevent frost damage to outdoor units of Monoblock heat pumps
• Drains the heating water if there is a risk of frost due to a power failure, defective Circulation pumps or similar
• Installation required outdoors in the supply and return flow pipe
• Installation in vertical pipework
• Opens at a medium temperature of +3°C, closes at a medium temperature of +4°C

Technical data:
• Ambient air temperature: -30°C to 60°C
• Media: water, water/glycol mixture up to 30%
• Housing material: brass
• Discharge capacity:
- 0.5 l/h (at -5°C and 3 bar)
- 1 l/h (at -20°C and 3 bar)

• For heating operation up to 90°C
• Without ambient air sensor
• Operating pressure: max. 10 bar
• Operating temperature range: 0°C to 90°C