Description
AVG Expansion Control Valve 20mm 700KPA
ECV Function
The Expansion Control Valve (ECV) is designed to relieve the increase in pressure caused by the water expansion during the normal heating cycle. It is recommended that an ECV be fitted to the cold water supply line. This will relieve cold water, not hot water, during the heating cycle saving energy and increasing the life of the Pressure Temperature Relief valve (PTR). Some local governments make it mandatory to install an ECV in the cold water line. PTR and ECV valves are safety valves and should be replaced every 4 years.
Inlet Pressure Control
High pressure may cause excessive discharge and possible premature failure of the operating relief valve (see table). The maximum water pressure usually occurs during the night, at the time of lowest water usage. In any mains pressure water heater installation if the water pressure exceeds 80% of the nominal set pressure of the operating relief valve, a Pressure Limiting Valve must be fitted to the cold inlet. If a cold water expansion control valve is fitted it will have a lower set pressure than the PTR valve and therefore will be the main operating relief valve.
The tempering valve may be installed at the point of use, but there must be a minimum 1 metre pipe run between the valve and the outlet tap. Caution: Water escaping from the drain line may be hot and could cause scalding. This valve is a Safety Valve. Excessive discharge from the drain line or operation of the small auxiliary relief valve opposite the drain can mean a malfunction within the system. Switch off the energy source and call a plumber or service person.
In addition to these instructions, ECV Valves must be installed in accordance with AS/NZS3500 National Plumbing and Drainage Code. All local government requirements must be met and the PTR must be installed in line with the water heater manufacturer’s instructions. The ECV to be fitted must have a set pressure lower than that of the pressure temperature relief valve (see “Set Pressures for Water Heater valves” Table above.)
- Australian Valve Group (AVG) Expansion Control Valve should be installed by a licensed plumber in accordance with AS/NZS3500.
- Clean out any foreign matter from the valve before fitting a valve
- Flush the plumbing lines before connection. Deposits left in the line can lodge under the valve seat causing the valve to leak.
- Apply thread seal tape to the thread. Be sure not to use excessive amounts of thread seal that could hang over the thread, break off and lodge under the valve seat, causing it to leak.
- Install the expansion control valve between the non-return isolating valve and the heater inlet
- Do not use a wrench on the valve body. Use the spanner flats provided.
- No valve, taps, or other isolating valves are to be fitted between the ECV and the water heater.
- If a drain line is fitted it must be of the same nominal pipe size as the valve, in accordance with AS/NZS3500.4. The drain line must have a continuous fall.
- Test the manual relief by lifting the lever. Water should flow out of the relief. It is recommended that the manual relief be operated every 6 months, so as to flush out any deposits that may accumulate under the seal.
