Summary of Contents for Xylem CLEGHORN WARING CW385
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The supplier accepts no responsibility for use of the tank for any other purpose than those described in these instructions. Xylem Water Solutions UK Ltd • Bingley Road • Hoddesdon • Hertfordshire • EN11 0BU Telephone: +44 (0)1462 480380 Fax: +44 (0)1462 482422 mail@cleghorn.co.uk...
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Accumulator Tanks and Expansion Tanks - What’s the difference? There is no difference in construction. Cleghorn Waring’s tanks are suitable for either duty. They are cylindrical steel tanks with an internal rubber membrane. The tank is supplied charged with inert nitrogen gas, to prevent internal corrosion.
SECTION A - ACCUMULATOR TANKS Why do I need an accumulator tank? An accumulator tank is an important part of any pressurised water system that includes a pressure-controlled pump. (Some modern computer-controlled pumps may not require an accumulator tank, but see Section B - Expansion tanks.) Fitted close to the discharge port of the pressurised water pump, the accumulator tank acts as a pressure buffer, ensuring a smooth flow of water from the outlets.
2 - 3 psi below the cut-in pressure of the pump (refer to pump instructions for details). This pressure adjustment is best done before installation of the tank, using a car-type pressure gauge to determine when the required pressure is reached, as follows: Depress the central pin of the Schrader valve with your finger, to release Release gas a little at a time, until the pressure is correct iii.
SECTION B - EXPANSION TANKS Why do I need an expansion tank? Heated from 10 to 60ºC, water expands in volume by about 2%. The calorifier expands too, but not as much as the water. A litre or more of hot water may need to escape from your calorifier as it heats up.
STEP 1 From the table, find the volume factor appropriate to your system STEP 2 Divide the volume of your calorifier by the volume factor, to give the expansion tank volume you require EXAMPLE A 50 litre calorifer having a relief valve setting of 2.5 bar with a pump cut-out pressure of 1.4 bar (21psi).