16
Mild Steel
Copper
Elbows
Tees
90º Bends
up to 25
up to 28
0.5
0.5
0.3
32 top 40
35 to 42
1
1
0.3
50
54
1.5
1.5
0.5
80
76.1
2.5
2.5
1
Nominal size (mm)
Appropriate additional lenghts
to be allowed (m)
Mild Steel
Copper
Elbows
Tees
90º Bends
up to 1
up to 1
2
2
1
1 ¼ to 1 ½
1 ¼ to 1 ½
3
3
1
2
2
5
5
2
3
3
8
8
3
Nominal size (ins)
Appropriate additional lenghts
to be allowed (ft)
The effects of elbows, tees or bends inserted in a run of pipe (expressed as
the approximate additional lengths to be allowed)
To make use of the tables on pages 14 and 15 the run of gas pipework from the meter to
the water heater must first be decided. Then, the length of the run (or the longest run
when more than one water heater is installed) is measured together with the numbers of
elbows and/or bends and tees counted.
The gas flow requirements of the water heaters are taken from the table on page 6. The
pipe size of the run, or the main part of the run for several water heaters, is assessed from
the tables on pages 14 and 15.
The effect of the fittings is then taken, from that pipe size, out of the tables on page…
The whole run is the re-checked for this size to ensure the overall pressure drop from the
meter to the water heater is within the prescribed limit. If several water heaters are
involved, the prescribed limit is proportioned over the different lengths of pipe with
different flow rates.
If you have any queries concerning the gas pipe work,
call Atlantic 2000 on 0161 621 5960
PO Box 11 Ashton Under Lyne OL6 7TR
+44. (0) 161 621 5960 Fax +44. (0) 161 621 5966
www.atlanticboilers.com
