RKI Instruments Digester Gas Monitor - Manual (Page 35)

Digester Gas Monitor Operator’s Manual Making Fitting Connections • 29
Compressed Air Inlet Fitting and Compressed Air Filter/Water Trap
1. A filter/water trap must be installed in the compressed air inlet line as close to the
Digester Gas Monitor as possible. The filter/water trap has compression fittings for
connection. The filter/water trap is not factory installed and must be field installed. It is
shipped separately from the Digester Gas Monitor. Rigid metal tubing is
recommended for compressed air inlet fitting connections.
2. If the filter/water trap will be installed where it’s unlikely to be bumped, the metal
tubing is strong enough to support the filter/water trap. If it’s likely that the filter/water
trap will be bumped, it should be mounted to a wall as close to the Digester Gas
Monitor as possible using screws and the filter/water trap’s bracket.
3. Install a short length of 1/4 inch OD rigid metal tubing that will connect the
compressed air inlet fitting to the filter/water trap into the tube nut and ferrules of the
compressed air inlet fitting on the Digester Gas Monitor.
Figure 17: Compressed Air Inlet Fitting Connection
Compressed Air
Inlet Determine
length based
on installation
1/4 inch OD tubing rated for pressure
supplied
Stainless steel,
copper, or
aluminum
* It is not necessary to route the dryer exhaust away from the digester, but it may be done if desired.
Table 4: Compression Fitting Maximum Tubing Lengths
Fitting
Maximum
Tubing Length
(ft.)
Recommended Tubing Size
Recommended
Tubing Material
Hold Still (5/8 inch)
Ferrule
Compressed Air Fitting
1/4 inch OD
rigid metal
tubing
Nut (9/16 inch)