Burn
Mailing pressure score. Sends accumulate it; clicks, opens, and time drain it. No ceiling.
Burn measures how much send pressure a contact is currently under. It has no upper cap — a contact on a daily acquisition list can legitimately read 200+.
Formula
burn = MAX(0,
(sends_last_30 × sendWeight)
− (clicks_last_30 × clickWeight)
− (opens_last_30 × openWeight)
− (daysSinceLastSend × burnDecayRate)
)All four weights are configurable in the Config tab. Defaults: sendWeight: 3, clickWeight: 10, openWeight: 5, burnDecayRate: 0.5.
Suppression thresholds
When burn crosses suppressBurnT1 (default 40), Hearth flags the contact ▲ NON-CRIT — suppress from non-critical sends only.
When burn crosses suppressBurnT2 (default 70), the flag becomes ▲▲ ALL SENDS — suppress from everything.
Both thresholds are configurable. Set them to match your organization’s acceptable send frequency before running scores.
What drives it up
- High
sends_last_30with no corresponding engagement - Short time since last send (low decay relief)
What drives it down
- Clicks and opens (the contact is engaged — pressure is warranted)
- Time passing without sends (decay drains it automatically)
- Explicit suppression, which stops new sends from accumulating
Reading the output
A contact with Burn = 0 has either been inactive long enough for full decay, or their engagement has kept pace with volume. Neither is inherently good — context from Recovery and Heat matters.