Residual air load removal per rack
Twenty kilowatts of air load in a rack position designed for eight is still an air problem.
What runs out
Heat removable from a single rack position by air, at the hall's containment and airflow.
The relation that governs it
Residual air per rack = rack kW × (1 − liquid capture). The hall's per-position air capability — commonly 10–20 kW with good containment — is what it must fit inside.
Worked example
What must one rack position remove by air?
135 kW × (1 − 0.90)
13 kW at one position
Good containment gets a position to roughly 10–20 kW.
Reproducible by hand. A page that asks you to trust a number has taught you nothing.
How to tell whether it binds in your hall
Compare the residual air load of one target rack against what one position in your hall can actually remove today. Containment quality decides this more than plant capacity does.
What relieves it
In-row cooling or rear-door heat exchangers at the affected positions.
What that relief costs beyond money
Rear doors need water at the position, which is a pipework and leak-detection question in a live hall.
Indicative relief lead time
10–30 weeks
European retrofits. The schedule, not the capex, usually decides.
How we currently price this relief
E0
A placeholder with a −50%/+100% band, not a price. It is replaced by a quotation the first time we tender this relief on a real project.
The mistake we actually see
Per-position capability inferred from hall-average density. The average is not the limit; the position is.
Basis
- — Uptime Intelligence on practical retrofit density ceilings.
These usually travel together
Does this one bind in your hall?
Seven numbers you already know, all thirteen constraints evaluated, and the one that stops you first named with its basis in engineering units. Free.