Figure 5-20.Operating controls and component indentification of Clayton steam generator, Model RO-33-PL, rear view.
burner causes reduced burner efficiency. The
frequency of cleaning depends on the amount of
dirt or lint in the air at the installation.
Check the operation of the thermostat control
every 100 operating hours. Consult the
manufacturer's instructions for test procedures.
When a water pump is noisy, the trouble is
sometimes due to a restricted heating coil that
causes excessive feed pressure. The feed
pressure should be checked for coil restriction.
When checking for coil restriction, compare the
reading on the feed pressure gauge with that on
the steam pressure gauge. Normal feed pressure
may vary slightly with each installation.
Carefully note the pressure right after the steam
generator is installed, so an accurate check of
coil restriction can be made for the unit. The coil
is restricted if feed pressure is 30 pounds or more
above the normal feed pressure noted
immediately after installation or when the coil
was completely clean.
The steps of the procedure used to blowdown the
system are as follows:
1. With the plant operating at normal steam
pressure, close the circulating feed valve (E) and
open the coil drain valve (J). Start a time check.
After 30 seconds, shut off the burner and close
the steam discharge valve (B).
If the burner is shut down by the thermostat
c o n t r o l d u r i n g t h e t i m e c h e c k ,
immediately open the burner control valve
(K); then close the steam discharge valve.