DC HVAC study plan

Explain the three heat transfer modes with one data hall example each for conduction, convection and radiation

Convert between kW, tons of refrigeration and BTU/h for five sample IT loads without a calculator error

Define sensible heat ratio and compute it for a mixed IT-plus-humidification load

Sketch the psychrometric chart axes and label dry bulb, wet bulb, dew point and enthalpy lines

Distinguish design conditions, part-load conditions and ASHRAE allowable envelopes for IT equipment intake

Decompose a data centre load into IT, lighting, UPS losses, fan energy, envelope and humidification components

Calculate PUE, pPUE and partial PUE for a worked example and explain which boundary each uses

Compute cooling capacity required for a stated IT load at a given redundancy level (N+1, 2N)

Explain how altitude, ambient design temperature and humidity setpoints shift available capacity

Interpret a simple annual load duration curve and estimate hours spent below 50 percent load

Describe chilled water, direct expansion, and air-cooled versus water-cooled condenser configurations with their trade-offs

Trace refrigerant flow through a vapour compression cycle and label each state point on a pressure-enthalpy sketch

Compare computer room air conditioner, in-row, in-rack and rear-door heat exchanger units by application

Explain economiser types (air-side, water-side, refrigerant-side) and the climate conditions each needs

Identify the role of pumps, valves, cooling towers, chillers and buffer tanks in a chilled water loop

Calculate required supply airflow from sensible load and a chosen temperature differential

Explain the difference between open aisle, hot aisle containment, cold aisle containment and full enclosure

Identify bypass airflow, recirculation and leakage paths on a given rack layout description

Apply the concept of air change rate and perforated tile free area to a raised floor design

Describe how rack inlet temperature varies across a row and why the hottest inlet governs

Compute return temperature index and bypass ratio from given supply, return and rack inlet temperatures

Evaluate the effect of blanking panels, brush strips and sealed cable entries on recirculation

Explain how containment changes economiser hours and PUE

Size a CRAC or CRAH unit count for a given load with redundancy, including airflow per unit

Describe commissioning tests for airflow: thermal imaging, CFD comparison and tracer methods

Build a preventive maintenance calendar covering filters, belts, coils, condensate drains, chillers and cooling towers

Explain water treatment risks in cooling towers and evaporative systems and the controls used

Compare setpoint strategies: supply air temperature reset, chilled water temperature reset and deadband control

Describe common failure modes such as loss of condenser water, refrigerant leak and fan failure, with detection methods

Outline a change management process for a setpoint change including risk review

Interpret trend data to spot simultaneous heating and cooling, valve hunting and sensor drift

Calculate energy savings from a supply air temperature reset using degree-hours or a simple bin method

Explain free cooling hours estimation and compare it against actual economiser runtime

Apply ASHRAE or equivalent energy audit levels to a data centre and list what each level requires

Draft a corrective action for a hall running at PUE 1.9 with a target of 1.4

Re-derive every formula from weeks 1 to 7 from memory and check against your formula sheet

Complete a timed mixed-topic practice set and log errors by domain

Re-teach the three weakest topics in writing without notes

Review flagged uncertain facts and confirm each against a reliable reference

Simulate explaining a full cooling design to a non-specialist in five minutes