Robur GAHP Line AR Series, Installation, Use And Maintenance Manual

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GAHP-AR – Installation, start-up, use and maintenance manual
42
Edition: 2014-08
SPECIFIC GRAVITY OF NATURAL GAS
BTU CONTENT PER CU.FT.
0,555
1014 2,77 IN. W.C.
Table 15 - Manifold pressure based on gas input (HHV) of 95,500 Btu/hr USING 0.21” orifice.
The conditions referred to by the table above are for the guidance of the installer and the
CSA design certification does not cover the conditions described therein.
Note: For Propane Gas Models, follow the same instructions as given for natural gas. The
manifold pressure for propane gas should be 5.1” W.C., manifold pressure at 95,500
Btu/hr. input using 0.14” orifice.
GAS TYPE NATURAL GAS LP GAS
MANIFOLD PRESSURE
2.8 WC INCHES 5.1 WC INCHES
NOZZLE DIAMETER
0.21” 0.14”
Table 16 - Manifold pressure and nozzle diameter.
Pressure adjustment procedure
You will need: the unit shut off; a manometer.
1. Turn main gas valve knob to the “OFF” position.
2. Remove the plug on Outlet end of gas valve and attach pressure tap and
manometer.
3. Turn power “ON,” and close control switch.
4. Wait for the burner to start up. Due to the presence of air inside the piping, it may be
that the burner does not start at the first three attempts and failing to do so the
ignition system is locked out. If this happens reset the ignition system (see dedicated
procedure, end of Appendix). Repeat until all the air is purged from the piping and
the burner ignites.
5. When the burner ignites read the manometer and compare to the required pressure
in Table 15 or Table 16.
6. If necessary change the manifold pressure using the gas valve regulator. The
regulator is built into the gas valve. Remove the seal screw and turn adjusting screw
clockwise to increase pressure or counter clockwise to reduce pressure. Replace
seal screw after adjustment.
7. Open control switch and make sure unit is off.
8. Remove manometer and pressure tap. Replace plug in gas valve.
9. Turn unit on by closing control switch. Check all gas connections with soap for leaks.