District cooling and campus loops
When a campus bills buildings for cooling, the meter is the invoice. Verifying it independently is not an accusation, it is due diligence on a six-figure annual charge.
Verifying a thermal billing meter
Permanent BTU meters on a district cooling loop drift, and the two things that drift are the flow element and the temperature sensors. A clamp-on meter with its own temperature probes checks both at once, independently, without interrupting service to the building.
Install on the same line at a location with good straight run, log for a week alongside the permanent meter, and compare totalised energy. A consistent percentage offset points at the flow element. An offset that varies with load usually points at temperature measurement or a delta-T that has collapsed.
Capacity and expansion planning
Campus loops accumulate buildings over decades, and the loop that was sized for eight buildings now serves fourteen. Measuring actual flow and thermal load at the plant and at each branch tells you where the hydraulic headroom actually is, which is the input to any expansion decision.
Large-diameter measurement notes
- Flow profile matters more. On a 24 inch line, ten diameters is 20 feet. Where you cannot get it, the UF801-P's automatic Reynolds correction helps, but it does not substitute for straight pipe.
- Sensor spacing grows with diameter. On large pipe the transducers may sit several feet apart. Confirm you have accessible pipe over that whole span, not just at one point.
- Reflex versus diagonal mounting. On large diameters, diagonal (Z) mounting gives a stronger signal than reflex (V). Plan for access to both sides of the pipe.
- Buried and tunnelled mains. Campus loops often run in service tunnels, which is good access. Direct-buried sections need a chamber.