Keep PE-X a minimum of 500 mm from sources of high heat such as heating appliances, flues from heating appliances etc.
Keep PE-X 1500mm from slow combustion type stoves and flues used to heat hot water or cooking (wet back type).
Leave 300mm minimum space between PE-X pipe and recessed electric light fittings.
PE-X should not be positioned within 150mm of gas or central heating vents or flues.
In the case of uncontrolled heat sources, i.e. slow combution stoves, water heating coils, wet back boilers, solar or thew like, PE-X pipe should not be used. The primary flow and return on these types of heaters should not be installed in PE-X.
Secondary flow and returns must be controlled so that the temperature/pressure requirements are not exceeded. (See derating table.)
In the interest of safe temperature and to protect the user, tempering valves should be installed in accordance with A.S/NZS.3500 4.2.
When using solar systems, installers should consult with manufacturers to ensure that water leaving the storage facilities does not exceed the performance capabilities of the pipe. Primary flow and returns should not be installed in PE-X and secondary flow and returns must be controlled. (See derating table)
Consult with the manufacturer regarding direct sunlight applications.
Q: How much head loss (pressure drop) occurs in an Auspex 16 mm PE-X pipe carrying hot water at 70°C with a required flow rate of 0.1 Litres/Second?
A: Place a ruler on the 0.1 Litres/Second mark on the bottom of the chart and measure up to cross the sloping line for the 16mm pipe. From this point draw a horizontal line to the line left hand side of the chart. This gives a head loss of 0.8 KPa/metre of pipe length. Multiply this value by the length of the total pipe to give the total head loss in the pipeline in KPa. The velocity of flow in the pipe is approximately 0.9 metres/second.
The AUSPEX flow charts are calculated for water at 70°C temperature. Where the water is at a different temperature the values from the chart need to be adjusted. Multiply the head loss by the appropriate factor in the table.
AUSPEX pipes are made to A.S.2492 dimensions for PN16 pressure ratings. Tighter manufacturing specifications ensure that bore sizes on all pipes are always at the maximum allowable.
Temperature loss from PE-X is very low compared to metallic products. For more specific calculations, the formula for thermal conductivity is:
1.1 x 10-3 cal/sec/cm/°C
or 0.46 W/mK (Watts per metre Kelvin)
| Size | Mean OD | Min Wall | Max Mean ID |
|---|---|---|---|
| 16 | 16.0 | 2.0 | 12.3 |
| 20 | 20.0 | 2.3 | 15.7 |
| 25 | 25.0 | 2.8 | 19.7 |
| Water °C | 20 | 30 | 40 | 50 | 60 | 80 | 90 |
|---|---|---|---|---|---|---|---|
| Factor | 1.20 | 1.14 | 1.10 | 1.05 | 1.02 | 0.98 | 0.95 |
The noise emitted by the pipes through the wall was mainly evident in the mid to high frequencies of the A-weighted spectrum.
Noise emitted at frequencies below 250Hz was affected by the level of background noise in the room.
The change in radiated noise level was greater with the change in water flow compared with the change in water pressure.
In all cases the overall noise level emitted by the Auspex pipe was less than for the copper pipe. For the same flow conditions the differences in overall noise level between the pipes was between 14 and 17dB(A).
Measurements of noise emitted from nominal 15mm bore pipes attached to the other side of a concrete block wall with water flowing through them and a noise source in the pipe showed that the Auspex cross-linked polyethylene pipe was between 14 and 17dB(A) quieter than the standard copper pipe.
| Measured Noise dB(A) |
Level Difference dB(A) |
|||
|---|---|---|---|---|
| Waterflow L/min | Water Pressure kPa | Auspex | Copper | Copper - Auspex |
| 15 | 300 | 38 | 55 | 17 |
| 15 | 600 | 40 | 54 | 14 |
| 20 | 600 | 45 | 62 | 17 |
| 20 | 700 | 45 | 62 | 17 |
