BUNN making weak or slow coffee — the deliming spring

What this error means

Scale. BUNN's documented fix is wonderfully specific: remove the sprayhead, insert the deliming spring (it shipped with the machine — check the drawer nobody opens) fully into the sprayhead tube until no more than about 2 inches remains visible, and saw it back and forth five or six times. BUNN says hard-water areas may need this daily — it takes under a minute. Clogged sprayhead holes and the wrong grind/filter are the other documented culprits.

Symptoms

• Coffee progressively weaker over weeks
• Brew cycle slower than it used to be
• Sprayhead dribbling instead of spraying

Try this first (safe DIY steps)

1. Unscrew the sprayhead; clear each hole (toothpick) and wash it
2. Insert the deliming spring into the sprayhead tube, saw back and forth 5–6 times, remove
3. Run a water-only brew to flush loosened scale
4. Lost the spring? BUNN sells them for a few dollars — or order with the next supply run
5. Check grind and filter type match the brewer spec

Safety: power off before any physical intervention. Never bypass covers or interlocks — fuser areas run hot enough to burn.

When to call a technician

If deliming doesn't restore flow, tank-level scale needs a proper service or replacement decision.