Filling Valve with CA Device - Systems up to 45 KW
Part Number: CA297
Backflow Prevention Device primarily intended for filling and pressurising sealed house heating systems, or non-house systems, which have an output of less than 45 KW. A Type CA device – with suitable pressure regulation – can be permanently connected to a small heating system without the need for a removable filling loop. This enables the system to be filled and pressurised. Boilers with an output of 45 KW or greater (except in a house) are considered by the Water Supply Industry to be a Fluid Category 4 risk and a BA device can be used for filling and pressurising – see "Autofill".
The CA device affords permanent Fluid Category 3 protection. The relief port affords better protection than a double check valve (Type ED) and a CA device may be permanently connected – no removable filling loop required.
A discharge pipe should be connected to the integral tundish. Under normal operation the unit should not discharge. The valve will discharge a tiny quantity of water if the supply pressure falls below about 0.5 bar or 110% of downstream pressure. A continuous discharge could occur if debris becomes lodged in the relief valve or the second check valve during a backpressure condition.
• Expansion Vessel (EVCP)
Where indicated on the drawing, a filling valve assembly shall be installed – model CA297PRV - as manufactured and distributed by Arrow Valves Ltd – Tel 01442 823123 www.arrowvalves.co.uk. The assembly shall consist of a CA device, which is suitable for permanent fluid category 3 protection, inlet and outlet servicing valve and pressure reducing valve complete with gauge. A 21.5 mm “overflow” type pipe shall be connected to the tundish. Whilst there is no operational discharge, provision should be made for a small discharge. The assembly shall be fitted in place of a filling loop.
(Fluid Categories 1 – 3)
• Filling house heating systems (of any output power)
• Filling non-house heating systems (less than 45 KW)
• Other applications approved by the local water company
• Filling Heating Systems