ACV HR s 1000, Installation Operation & Maintenance

Page: 21 / 36

Worked example of discharge pipe sizing
Figure on the left shows a G1/2 temperature relief valve with a discharge pipe (D2) having 4
No. elbows and length of 7m from the tundish to the point of discharge.
From Table:
Maximum resistance allowed for a straight length of 22mm copper discharge pipe (D2) from
a G1/2 temperature relief valve is 9.0m.
•
Subtract the resistance for 4 No. 22mm elbows at 0.8m each = 3.2m
•
Therefore the permitted length equates to: 5.8m
•
5.8m is less than the actual length of 7m therefore calculates the next largest size.
Maximum resistance allowed for a straight length of 28mm pipe (D2) from a G1/2 temperature
relief valves equates to 18m.
•
Subtract the resistance of 4 No. 28mm elbows at 1.0m each = 4.0m
• Therefore the maximum permitted length equates to: 14m
•
As the actual length is 7m, a 28mm (D2) copper pipe will be satisfactory.
Essential recommendations for safety
•
The temperature/pressure relief valve should only be replaced by a competent
person.
• No control or safety valves should be tampered with or used for any other
purpose.
• The discharge pipe should not be blocked or used for any other purpose.
• The tundish should not be located adjacent to any electrical components
UK
HR s & Jumbo : A1007851 - 661Y1200 • E
Installation
21
EN