Energy Tech Laboratories CL Series ユーザーズマニュアル

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V.  Maintenance and Service Instructions
A
.  MAINTENANCE  OF  LOW  WATER  CUT-
OFF  DEVICES
WARNING
Probe  and  float  type  low  water  cut-off  devices 
require annual inspection and maintenance.
1.   Although these devices are solid state in their 
operation, the probe is exposed to possible 
contamination in the boiler water and subject to 
fouling.
2.  It is important to physically remove the probe from 
the boiler tapping annually and inspect that probe 
for accumulation of scale or sediment.
3.  Follow these steps to inspect, clean and/or replace 
the probe:
a.  Turn off electric service to the boiler.
b.  Drain boiler water to a level below the tapping 
for the probe.
DANGER
Assure that the boiler is at zero pressure before 
removing  the  LWCO  probe.    Do  not  rely  on  the 
pressure  gauge  to  indicate  that  the  boiler  is  at 
zero  pressure.    Open  the  safety  valve  to  relieve 
all  internal  pressure  prior  to  proceeding.    Safety 
valve  discharge  piping  must  be  piped  such  that 
the potential for burns is eliminated.
c.  Disconnect wiring connections between the low 
water cut-off control and the probe.
d.  Remove the low water cut-off control from the 
probe.
e.  Unscrew the probe from the boiler tapping.
f.  Inspect that portion of the probe that is exposed 
to the boiler water for a scale or sediment 
buildup.
g.  Light deposits may be removed by wiping the 
probe with a damp cloth. Wiping the probe with 
a cloth soaked in vinegar will remove more 
tenacious lime deposits. The most stubborn 
deposits may be removed from the probe by 
using a diluted amount, 3 parts of water to 1 part 
of phosphoric acid (H
2
PO
4
).
CAUTION
Exercise caution when handling phosphoric acid 
and follow the instruction label on its container.
h.  Clean the pipe threads of the probe to remove 
old, hardened pipe dope and other foreign matter.
i.  Apply a moderate amount of good quality pipe 
dope to the pipe threads on the probe, leaving the 
two end threads bare. Do not use PTFE (Teflon) 
tape.
j.  Screw the probe into the boiler tapping.
k.  Mount the low water cut-off control on the 
probe.
l.  Reconnect the control to probe wiring.
m. Fill the boiler to its normal waterline.
n.  Add boiler water treatment compound as needed 
(refer to Paragraph B.).
o.  Restore electric service to the boiler.
p.  Fire burner to bring the water in the boiler to a 
boil to drive off free oxygen.
q.  WARNING — BEFORE  RETURNING  
BOILER TO  SERVICE:  Follow the low water 
cut-off check out procedure in Section IV. 
Operating & Service Instructions.
B.
  BOILER AND SYSTEM CLEANING 
INSTRUCTIONS FOR TROUBLE FREE 
OPERATION.
1.  STEAM BOILERS:
a.  Oil, greases & sediments which accumulate in a 
new boiler and piping must be removed from the 
system in order to prevent an unsteady water line 
and carry over of the water into the supply main 
above boiler.
 
Operate the boiler with steam in the entire 
system for a few days allowing the condensate 
to return to the boiler. If the condensate can 
temporarily be wasted, operate boiler only for 
the length of time it takes for condensate to run 
clear. If the latter cannot be achieved or if the 
condensate is returned to the boiler, boil out 
the boiler using the  SURFACE  BLOW-OFF  
connection.
i
Drain boiler until 1” of water is visible in 
gauge glass. Run temporary 1½” NPT pipe 
line from the surface blow-off connection to 
an open drain or some other location where 
hot water may be discharged safely. Do not 
install valve in this line.
ii.  Drain about 5 gallons of hot water from 
boiler into a container and dissolve into it 
an appropriate amount of recommended boil 
out compound. Remove safety valve & add 
solution to boiler water thru exposed tapping 
using a funnel.