Rules for the use and installation of above-ground tanks

Installation must be carried out by qualified persons, in compliance with the regulations in force, including Romanian occupational-safety rules, and with these instructions.

The tank installation area must be large enough to allow installation, handling and maintenance. The surface on which it is installed must be firm and even, able to support the weight of the full tank. We recommend installing the tanks in technical rooms with low humidity, not exposed to UV radiation or frost.

When installed in high-humidity spaces there is a risk of condensation; in such cases, the tank must be insulated.

Before installing the tank and its associated system, check the following:

• The tank surface must be free of defects visible to the naked eye or of deformations that could affect functionality (inclusions, scratches, cracks or peeling layers).
• The tank must be empty, clean and watertight (no visible signs of transport damage).

If the tank is used as a buffer tank, it is mandatory to:

• install the tank only in a technical room that is mandatorily fitted with a floor drain;
• fit an overflow on the tank, connected to the sewer, to prevent — in the event of a feed shut-off failure — the tank being subjected to pressure above the normal operating pressure;
• fit the air vent valve on the lid.

To connect the tank to installations you can use the internally-threaded brass inserts pre-mounted on the tank (data available in the StockKIT catalogue and in the tanks’ technical specifications), or fit a nipple–nut kit on a flat area of the tank (the kit is supplied on request).

Using the brass inserts provided on the tank

Drilling the metal insert pre-mounted on the tank must be done only with suitable cutters/hole saws. While drilling, the cutter must not touch the thread.

Connecting the tank through this metal insert must be done ONLY with a flexible pipe/hose, to avoid stressing the tank walls during liquid filling/emptying.

The threaded joint must be sealed ONLY with Teflon® (PTFE) tape. Do NOT use hemp packing or sealing liquid/paste.

Installing the nipple–nut kit

The nipple–nut kit is installed only on perfectly flat areas of the tanks. Sealing between the kit and the tank walls is achieved with gaskets.

Available sizes for the nipple–nut kit:

Gaskets for installing the kit:

• gaskets for the FE connector — 2 gaskets required for installation; they seal inside and outside against the tank wall;
• gasket for the FI plug — 1 gasket required for installation, when the plug is used to close off the connector.

The order of the parts at installation is as shown in the diagram.

For installing the kit you need: a marker pencil, a tape measure, a power drill with a cutter and a cutter knife. The correspondence between cutter sizes and kit sizes is as follows:

Kit — d [″]	Cutter — D [mm]
1″	33
1″ 1/4	43
1″ 1/2	48
2″	59
2″ 1/2	75

Kit installation steps

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Connecting the tank via the nipple–nut kit to a polyethylene-pipe installation

For the connection you need: Teflon tape, an FE compression fitting matching the kit size, and a polyethylene pipe of the matching size.

Make the connection following these steps:

• Prepare the nipple, wrapped with Teflon tape.
• Fit the compression fitting onto the prepared nipple and connect the polyethylene pipe, following the installation instructions for compression fittings (the ones found at VALWater), as follows:

• unscrew the blue nut on the fitting by 3–4 turns;
• measure and mark how far the pipe must enter the fitting, so that it passes the O-ring and reaches the inner shoulder;
• insert the pipe into the fitting up to the mark; note: the pipe must have clean, straight edges, preferably chamfered, so it does not catch the gasket;
• tighten the nut depending on the size: by hand (OD 20, 25, 32) or with the compression-fitting wrench (40, 50, 63, 75).

Installing the air vent valve

The air valve for water tanks allows air to enter or escape in order to maintain atmospheric pressure, regardless of the fluctuations in the liquid level inside the tank. For installation you need: a power drill with a D32 cutter and a cutter knife. The valve is installed on the tank lid, following the steps in the images:

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Commissioning

Before use, polyethylene tanks must be ventilated for 24 hours and then washed with water and detergent.

Maintenance: check the tank periodically and, in case of deposits, wash it with a pressurized water jet and/or with water and dish detergent, using a soft sponge.

Spare parts for above-ground tanks

Lids and gaskets can be supplied on request. Lid dimensions are specified in the Valrom documentation and in the tanks’ technical specifications.