
PRV misuses cause avoidable breakdowns
Published: 02-11-2018
- A Pressure Relief Valve (PRV) can last the lifetime of a boiler as it isn’t a wearable part.
- If a PRV is used incorrectly however, it can quickly become irreparably damaged and lead to a breakdown.
- It is important to never use the PRV to drain a heating system down or it will eventually need to be replaced.
Boiler breakdowns caused by the incorrect use of the Pressure Relief Valve (PRV) component to drain a heating system down, could be avoided indefinitely, according to Martyn Bridges, our Director of Technical Communication and Product Management.
“It’s not unusual for PRVs to last the lifetime of a boiler if used correctly, as a PRV isn’t a wearable part”, comments Martyn. “If a PRV is used incorrectly though, it can quickly become irreparably damaged and lead to a breakdown.”
Martyn explains: “This isn’t what PRVs are designed for and can cause complications, yet due to PRVs being situated at the bottom of a boiler, in addition to being attached to a permanent pipe, it can be tempting to drain a system this way.”
“If a PRV is used to drain a system, any contaminants in the heating system are drained through the valve itself and end up on the seating of the valve where the valve should re-seal and shut off again.”
Martyn, continues: “An obvious symptom of this is water dripping periodically from the valve outside once the heating system is put back into operation. For the homeowner, this means they must re-pressurise the heating system from time-to-time, but ultimately, the PRV needs to be replaced.”
“The only places that a system should really be drained from are drain-off valves located at all low points in the system or drops to radiators from above.”
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