9
DRISTEEM GTS HUMIDIFIER INSTALLATION AND OPERATION MANUAL
• When the specifi c gravity of the gas is other than 0.60 for natural gas or 1.53 for propane, refer to Table 9-1.
• Piping to GTS humidifi ers should conform with local and national requirements for type, volume, and gas handled
and for pressure drop allowed in the line. Refer to the tables on this page to determine the gas fl ow in m
3
/hr for the
type of gas and size of humidifi er to install. Using this value and the length of pipe necessary, determine the pipe
diameter.
Where several GTS humidifi ers are served by the same main, the total capacity, gas fl ow, and length of main must
be considered. Avoid pipe sizes smaller than DN15. Table 9-2 allows for the usual number of fi ttings with a 0.7
mbar pressure drop.
WARNING
Fire or explosion hazard:
Purge air before lighting humidifi er burners by disconnecting piping at gas control. In no case should line be
purged into heat exchanger. Failure to follow these instructions could cause a fi re or explosion, resulting in bodily
injury, death, or signifi cant property damage.
Gas pressure test gauge
Install a DN6 plugged tapping, accessible for test gauge connection, immediately upstream of the gas supply
connection to the appliance. Use this tap to check pressure with all burners running.
Leak testing
After installation, check fi eld piping and humidifi er gas train for gas leaks.
• Do not use soap solution or open fl ame on humidifi er gas train. A gas leak detector is recommended.
• When leak-testing the gas supply piping system, isolate the humidifi er from the gas supply piping system by closing
its fi eld-installed manual shutoff valve whenever pressure is greater than 60 mbar.
Table 9-2:
Gas pipe capacities for gas pressures of 3.45 kPa or less
Length of pipe
Gas fl ow in piping in m
3
/hr at pressure drop of 0.07 kPa
Specifi c gravity = 0.60
Nominal iron pipe diameter in inches (DN)
DN15
DN20
DN25
DN32
DN40
m
m
3
/hr
m
3
/hr
m
3
/hr
m
3
/hr
m
3
/hr
3
3.7
7.9
14.7
29.7
45.3
6
2.6
5.4
9.9
20.7
31.1
9
2.1
4.3
8.1
16.7
25.2
12
1.8
3.7
6.9
14.2
21.5
15
1.6
3.3
6.1
12.5
19.0
18
1.4
3.0
5.5
11.3
17.3
21
1.3
2.7
5.1
10.5
15.9
24
1.2
2.5
4.8
9.9
15.0
27
1.1
2.4
4.5
9.1
13.9
30
1.1
2.2
4.2
8.6
13.0
Table 9-1:
Specific gravity conversion factors
Natural gas
Specifi c gravity
Factor
0.55
1.04
0.60
1.00
0.65
0.962
Propane gas
Specifi c gravity
Factor
1.50
0.633
1.53
0.626
1.60
0.612
Note:
Use the above multiplying factor with
Table: 9-2 when the specifi c gravity of
gas is other than 0.60 (natural gas) or
1.53 (propane).
Gas piping