Cooling & Heating Water

Liquid-Cooled Server Room (IRHX)

Liquid removes heat in row and returns cooled air to the aisle.

Measures: Coolant flow · Supply and return temperature · Differential pressure · Fan and pump status

Used in:Data Centres

Diagram of the measuring points in a liquid-cooled server room (irhx)

1 2 3 4 5 6 7 8

Click a number to jump to that measuring point. Conceptual view, not for installation design.

Facility Water Flow & Energy

Meters chilled facility water delivered to the in-row heat exchangers so cooling energy per rack row is tracked.

Dwyer IEFB Insertion Thermal Energy Meter; Adj. 4"-36" PipesCurrent-Voltage-Pulse Outputs, Alarms; Optional BACnet & Modbus; 10', 20', 50' Sensor Leads

Dwyer Series-PFT Paddlewheel Flowmeters for Liquid Monitoring, Brass/316 SS, 4-20 mA OutputDwyer PFT paddlewheel flow sensor for water-based liquids in 1-1/2 to 40 in pipes: one adjustable insertion sensor, pulse or 4-20 mA output, brass or 316 SS.

Fixed MinisonicFaure Herman single-chord clamp-on transit-time ultrasonic flowmeter for liquids, with OLED display, 4-20 mA output, two contact outputs and a 1.8 GB data logger.

Uf821 Ultrasonic Fixed FlowmeterFaure Herman fixed clamp-on ultrasonic flowmeter for liquids: up to 4 measuring points per unit, accuracy to 0.5% of reading, on steel, PVC, cast iron or stainless pipes.

Facility Water Pressure & Differential Pressure

Watches supply and return pressure across the facility loop to confirm pumps hold head and coils stay unblocked.

Dwyer 626/628 SS316L Industrial Pressure TransmittersDwyer 626/628 industrial pressure transmitters with 316L stainless wetted parts: 626 ±0.25% or 628 ±1% full scale, 4-20 mA or voltage output, NEMA 4X.

Dwyer Series DX Wet to Wet Differential Pressure Switch; Use in most Gas/Water Based SolutionsSPDT Snap Switch; Contact Rating 5A @ 125/250 VAC, 5A Resistive @ 30 VDC; NEMAA 4X (IP65) Rated

Pump & Flow Verification

Confirms coolant distribution pumps are running and secondary loop flow is proven before IT load is applied.

Dwyer Series TDFS2 Thermal Dispersion Flow Switch (Non-Mechanical, Low Pressure Drop, Large Pipes)Measure Flow Above or Below User Set Flow Rate; Normally-Open & Normally-Closed NPN Outputs; LED Indication

Coolant Reservoir Level & Isolation

Detects low coolant in the CDU reservoir and provides isolation for service without draining the loop.

Dwyer F6/F7 Horizontal Mount Level Switch, Multi-MaterialOpen/Closed circuits; Water, oils & chemicals compatible; Through wall mounting

Dwyer Series 2000VA-3000WA High-Flow Control Valves – 50:1 Rangeability – Brass, Iron, SSHigh‑Flow Control Valve; Balanced Cage for Precise Control

In-Row Heat Exchanger Pressure Monitoring

Transmitters and gauges monitor coolant line pressure to ensure consistent flow through the heat exchanger. This data prevents pump cavitation and identifies system blockages to maintain thermal stability for liquid-cooled server racks.

Dwyer Series SGZ 2.5" Pressure Gage (0-160 psi, 316 SS, 1/4" NPT)Dwyer SGZ 2.5 in industrial pressure gauge, 316 SS wetted parts and 304 SS case: dual psi/bar scale, ±1.5% full scale, glycerin fill option.

In-Row Heat Exchanger Flow Sensing

Paddlewheel flowmeters monitor coolant velocity to ensure the heat exchanger receives sufficient volume for thermal transfer. Tracking flow rates allows for pump optimization and provides immediate notification of system blockages or pump failures that could lead to server overheating.