Burnham K50 Boiler User Manual


  Open as PDF
of 116
 
81
b. Probe Type Low Water Cut-off
It is important to physically remove the probe from
the boiler tapping annually and inspect that probe
for accumulation of scale or sediment. Follow these
steps to inspect, clean, and/or replace the probe:
1. Turn off electric service to the boiler.
2. Turn off gas supply to the boiler.
3. Drain boiler water to a level below the tapping
for the probe.
DANGER

        
        
     
 
   

4. Disconnect wiring connections between the low
water cut-off control and the probe.
5.
Dismount the low water cut-off control from the
probe.
6.Unscrewtheprobefromtheboilertapping.
7.Inspectthatportionoftheprobethatisexposed
to the boiler water for a scale or sediment
buildup.
8. 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
).
9. Wire brushing of the probe is not recommended
as the soft, platinum guard ring sandwiched
between ceramic insulators may be damaged.
Care must be taken not to damage this ring in
any way or the useful life of the probe may be
shortened.
IMPORTANT











10.Cleanthepipethreadsoftheprobetoremove
old, hardened pipe dope and other foreign matter.
11. Apply a moderate amount of good quality pipe
dope to the pipe threads on the probe, leaving the
two end threads bare.
12. Screw the probe into the boiler tapping.
13.
Mount the low water cut-off control on the
probe.
14. Reconnect the control to probe wiring.
15. Fill the boiler to its normal waterline.
16.Restoregassupplytotheboiler.
17. Remove the front door of the boiler and follow
the lighting instructions posted on the vestibule
panel.
WARNING

      

- Set thermostat to the highest setting.
- While boiler is operating, open drain valve
and slowly drain down boiler water.
CAUTION

- Main burners should turn off when water
level drops below low water cut-of. At this
point the water level in gauge glass will just
be visible.
-
Be sure that it is the low water cut-off
control and not the room thermostat,
pressure cut-out or other control that has
shut off the burners.
- Relltheboilertothenormalwaterlevel.
- Main burners should reignite.
- Clean out the boiler according to the
instructions for steam boilers on page 43.
- Reset controls for normal operation.
 previous next