Frese OPTIMA Compact Veriflow 53-5362 Manual, Specifications and Replacement Options

The Frese OPTIMA Compact Veriflow 53-5362 is a DN15 pressure independent balancing and control valve with a Low 2.5 mm stroke, covering flows from 30 to 200 l/h. It combines automatic balancing, differential pressure control and modulating control in one body, and is used on fan coil units, chilled beams and other terminal units in heating and cooling systems. Controls Traders sells it as the Siemens Veriflow Combi 15mm 0.056L/s (200l/h), and the full Frese datasheet is below.

Download the 53-5362 Manual

Download the Frese OPTIMA Compact Veriflow-series datasheet (PDF, 10 pages)

This is the Frese product datasheet for the whole OPTIMA Compact Veriflow-series, DN10 to DN50, English edition dated July 2024. The 53-5362 is listed in the Product Programme table on page 7. The datasheet also covers dimensions, actuator options, flow setting tables and the P/T plug measurement procedure. If you need background on how these valves work, read our guide What Is a Pressure Independent Control Valve?

53-5362 Specifications

The valve needs no straight pipe lengths before or after it, has a rangeability above 100:1, and accepts glycol mixtures up to 50% (ethylene or propylene).

Setup and Commissioning Notes

The datasheet does not list fault or error codes. These are the setup and commissioning steps it gives.

Set the flow before fitting the actuator

The presetting scale is not accessible once the actuator is mounted, so set the flow first. The dial is stepless, and the valve can be flushed and commissioned before the actuator goes on. For the Low 2.5 mm valve, these are the settings from the datasheet:

Measure flow with the P/T plugs

Insert a 4 mm hex key in the blue P/T plug and turn it clockwise until the indicator reaches the end stop marked Q. Place the manometer needles in the red and blue plugs to read the differential pressure P1-P2 across the presetting, then calculate flow as Q (l/h) = KV-signal x 100 x √Δp (kPa), using the KV-signal for your preset. Accuracy is ±5% of actual flow, and below 200 l/h it is ±10 l/h. Needles must be no more than 3.2 mm in diameter and 25 to 40 mm long.

Verify minimum differential pressure and set the pump

Turn the blue P/T plug anticlockwise to the end stop marked P and measure P1-P3 across the whole valve. Compare the reading with the minimum Δp for your preset (14 to 16 kPa on this valve). Frese recommends checking the differential pressure at the index valve so the pump can run at its minimum speed.

Choose a matching actuator

For the 2.5 mm stroke, the datasheet lists Frese thermic actuators 48-5525 (On/Off, 24 V AC/DC), 48-5526 (On/Off, 230 V AC), 48-5529 (0-10 V, 24 V AC) and 48-5529-1 (0-10 V, 24 V DC), and motoric actuators 53-1181 (3-pos or On/Off, 24 V AC), 53-1182 (3-pos or On/Off, 230 V AC) and 53-1184 (0-10 V or 4-20 mA, 24 V AC/DC). Motoric actuators 53-1180 and 53-1183 are listed for 5.0 and 5.5 mm strokes only.

Installation conditions

Ventilate the pipe system properly to avoid air pockets, and treat the water to VDI 2035. Below 0°C a stem heater must be fitted to stop ice forming on the spindle: Frese 58-8956 (24 V AC/DC, 10 W) suits DN10 to DN32 valves. With the isolation cap fitted, the valve can isolate to 10 bar.

Buy the 53-5362

Siemens Veriflow Combi 15mm 0.056L/s (200l/h), SKU 53-5362. This is the exact DN15 Low 2.5 mm F/F valve covered by the datasheet above.

If your terminal unit needs a different flow range, we also stock these sizes from the same OPTIMA Compact Veriflow-series:

• Siemens Veriflow Combi 15mm 0.160L/s (575l/h) (SKU 53-5364): Same DN15 F/F body in the High 2.5 mm version, 100 to 575 l/h, if the 200 l/h ceiling is too low.
• Siemens Veriflow Combi 20mm 0.369L/s (1330l/h) (SKU 53-5368): DN20 High 5.0 mm, 220 to 1,330 l/h, for larger fan coils.
• Siemens Veriflow Combi 25mm 1800lh (SKU 53-5339): DN25 Low 5.5 mm, 280 to 1,800 l/h.
• Siemens Veriflow Combi 25mm 3600lh (SKU 53-5373): DN25L High 5.5 mm, 600 to 3,609 l/h.
• Siemens Veriflow Combi 32mm 4000lh (SKU 53-5374): DN32, 550 to 4,001 l/h.

See the full range in pressure independent control valves, or use our PICV sizing and selection guide to match a valve to your design flow.