Pressure relief valve discharges water frequently through the safety pipe

Safety first: Allow the system to cool before working on pressurized components.

• Check system pressure: If cold pressure is above the recommended level, drain some water from a drain cock until it is within range.
• Test expansion vessel: See expansion vessel fault steps; a failed vessel will cause pressure spikes.
• Inspect relief valve: If the valve continues to drip even at normal pressure, it may be fouled by debris and require replacement.
• Check discharge pipe: Ensure the discharge pipe is not blocked or frozen, which can prevent proper operation.

Warning: Never cap or block the pressure relief discharge pipe; it is a critical safety device.