This document is a user manual for testo 312-4 · Pressure measuring instrument
This manual provides instructions for using the Testo 312-4 pressure measuring instrument, designed for heating system installations. It covers safety guidelines, technical specifications, product description, setup, measurement procedures, and maintenance. The device supports gas and water pipe testing, data transfer via IR printer or PC software, and includes various probes and accessories for extended functionality.
The manual also includes troubleshooting tips and lists compatible accessories with article numbers for easy ordering.
| Measuring ranges and accuracies | 0 to 3 hPa: ±0.03 hPa; 3 to 40 hPa: ±1.5 % of m.v.; 41 to 200 hPa: ±2 hPa |
|---|---|
| Intrinsic leakage | 0.3 % pressure drop from test pressure over a period of 1 minute |
| Permissible media | Air, non-aggressive gases |
| Voltage supply | 9 V monobloc (6LR61), alkaline manganese or 12 V DC mains unit |
| Measurement data memory | approx. 25000 readings |
| Battery running time | 30 h with alkali manganese at 25 °C / 77 °F |
| Storage/transport temperature | -20 to 70 °C/-4 to 158 °F |
| Operating temperature | 0 to 50 °C/32 to 122 °F |
| Weight (incl. TopSafe and battery) | approx. 600 g/1 lb 5 oz |
| Housing material | ABS |
| Dimensions (L x W x H) | 219 x 68 x 50 mm/8.5" x 2.5" x 2" |
| Measuring rate | Auto: 1 sec to 24 h, quick: 0.04 sec |
| Adaption time | 10 min |
| Refresh rate of display | 2/sec, with rapid measurement: 4/sec |
Battery voltage too low. > Replace battery.
There is a differential pressure outside of the range permissible for zeroing. > Reduce the differential pressure to a permissible value.
A factory reset was performed or the instrument was de-energized for a long period. > No remedy possible! Regularly save the readings (PC software, printout).