Pressure testing of water supply networks is carried out in order to test their functionality and identify weaknesses. By eliminating all the problems in a timely manner, you will ensure the operability of the pipeline and avoid serious damage.
The need for hydraulic testing
The operation is performed on a small segment of the line, which is isolated from the main line and is subjected to a high pressure test, bordering on the critical. A large volume of compressed air is pumped into the branch or a water flow is started under pressure. If the branch withstands this test and remains leakproof, it is deemed suitable for further use. A break will be indicated by a pressure drop on the pressure gauge.
The following shall be subjected to hydraulic tests:
- newly created highways;
- repaired networks;
- plastic piping after cleaning;
- pipe sections after replacing a damaged section or installing a coupling, tee;
- water pipes in the apartment after connecting water meters;
- heating systems before the heating season.
Pressure testing of wells is carried out in order to check the absence of contact of the transported liquid with the upper layers of water in the mine. This is necessary to accurately determine the depth of water intake.
Preparation for the procedure
Before testing, it is necessary to inspect the pipes for obvious defects and to eliminate them. You will also need to remove the coolant from the heating systems.
Further actions are as follows:
- Flushing the line to eliminate scale, corrosive and organic growths.
- Assessment of the condition of the inner surface of the pipes.
- Installation of a non-return valve and pressure gauge, if they are supplied with pressure equipment.
A non-return valve is required to hold the medium in the network.
In preparation for the procedure, it is also important to choose the right pump. Low pressure equipment will increase test time, which can lead to distorted results.
Units are manual and electric. A suitable one must be selected based on the volumes of the tested highways.
To pressure test the water supply system in a small private house or apartment, a supercharger pumping a couple of liters per minute through itself will be enough. Work on centralized water pipelines and heating mains involves the use of powerful circulation pumps. For air pressure testing, you can use a car compressor.
The order of work
Pressure testing of home water can be done independently.
- Seal the tested section of the trunk. To do this, close the stop valves at the end and beginning of the section.
- Disconnect elements of the system that are not designed for test pressure - safety valves and other fittings, boiler, boiler, expansion tanks.
- Connect pressure equipment. The pump is connected to the nozzle of a hot or cold water tap. In heating networks - to the radiator faucet.
- Pump water or air through the check valve.
- Monitor the pressure with a pressure gauge. For cast iron pipes, it should be 1.5 atmospheres, for non-pressure plastic products - 1.5–2, for pressure pipes - 10–15. When checking heating networks in private homes, 2 atmospheres is enough.
- Turn off the crimp and fix the primary value on the measuring device and leave the system for 6-8 hours.
After the control time, it is necessary to compare the initial indicator with the current result. If the first is lower, there are problems in the water supply system.
If the line is tested by water flow, leakage is not difficult to detect. During air pressure testing with soapy water, all the connecting nodes are smeared. Bubbles appear at the leak. After troubleshooting, testing is performed again.
SNiP and security measures
Pressure testing of the pipeline with water or air is regulated by building regulations:
- SNiP 3.05.01-85 is dedicated to communication networks;
- SNiP 3.05.04-85 - to the external highways;
- SNiP 41-01-2003 - the work of heating and ventilation systems.
In these documents, the procedure for conducting hydraulic testing is indicated, the technological schemes of this process and safety rules are prescribed.
The most important thing is to control the pressure indicators during testing. With their excess value, destruction of the main parts is possible. To insure against this, it is worth using a crimper with a special limiter.
Almost any intervention in the water supply and heating systems implies that after that a pressure test will be carried out. It will help to identify all weaknesses that cannot be visually found.
