Burnham 4FHL-107A, Инструкция по установке и эксплуатации

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Exercise caution when handling phosphoric acid and
follow the instruction label on its container.
Faire preuve de prudence lors de la manipulation
d’acide phosphorique et suivre les directives qui se
trouvent sur l’étiquette du contenant.
8. Wire brushing of the probe is not
recommended.
9. Clean the pipe threads of the probe to remove
old, hardened pipe dope and other foreign
matter.
10. Apply a moderate amount of good quality pipe
dope to the pipe threads on the probe, leaving
the first two threads bare. Do not use PTFE
(Teflon) tape.
11. Screw the probe into the boiler tapping.
12. Mount the low water cutoff control on the
probe.
13. Reconnect the control to probe wiring.
14. Fill the boiler to its normal waterline.
15. Add boiler water treatment compound as
needed (see Section III Item 8).
16. Restore electric service to boiler.
17. Fire burner to raise water temperature to
above 180°F to drive off free oxygen.
BEFORE RETURNING BOILER TO SERVICE: Follow the
low water cutoff check out procedure in Section III Item
4 Part C.
AVANT DE RETOURNER LA CHAUDIÈRE POUR UN
ENTRETIEN : Suivre la procédure de vérification du
dispositif de coupure du combustible en cas de bas
niveau d’eau de la section III, article 4, partie C.
B. Float Type Low Water Cut-Off During the
heating season, if external low water cutoff is on
the boiler, the blow off valve should be opened
once a month (use greater frequency where
conditions warrant), to flush out the sediment
chamber so the device will be free to function
properly.
Low water cutoffs and water feeders should be
dismantled annually by qualified personnel, to the
extent necessary to insure freedom from obstructions
and proper functioning of the working parts. Inspect
connecting lines to boiler for accumulation of mud, scale,
etc., and clean as required. Examine all visible wiring
for brittle or worn insulation and make sure electrical
contacts are clean and that they function properly. Give
special attention to solder joints on bellows and float
when this type of control is used. Check the float for
evidence of collapse and check mercury bulb (where
applicable) for mercury separation or discoloration.
DO NOT ATTEMPT TO REPAIR MECHANISM IN THE
FIELD. Complete replacement mechanisms, including
necessary gaskets and installation instructions, are
available from the manufacturer.
6 SURFACE BLOWDOWN PROCEDURE
The purpose of the Surface Blowoff connection is to
provide a means to remove impurities that collect near
the surface of the water level on steam boilers, and to
bleed off a small portion of the boiler water to lower the
level of TDS (total dissolved solids). This will decrease
boiler foaming and improve steam quality.
The following Surface Blowoff connections are
provided as standard:
A. Series 4FH: Sizes 63 thru 345, (1) fitting left side
of boiler, sizes 360 thru 3075, (1) fitting right side
of boiler.
B. The amount and frequency of surface blowoff is
based on the amount of TDS you are targeting,
the amount of make-up water, and the amount
of TDS in the make-up water. The following is an
example for a 250hp steam boiler:
1. Approximate evaporating rate at full capacity:
250 bhp x 34.5 = 8625 lb/hr
2. Make-up water (i.e. 20%): 1725 lb/hr
3. TDS of make-up water (i.e.): 400 ppm
4. Max TDS recommended in the boiler water:
3500 ppm
5. Reduction factor: 3500/400 = 8.75
6. Surface blowoff rate: 1725 / 8.75 = 197 lb/hr x
hr/60 min x gal/8.34 lb = .4 gpm
In this example .4 gpm would be the continuous
blowdown rate to keep the boiler water TDS at 3500
ppm. This is a good starting point and may need fine
adjustment during actual operation.
7. CHECK BURNER AND CONTROLS at least
once a year. See Item 4 under Operating
Instructions for control checks. See Burner Manual for
burner tests and adjustments.
8. LUBRICATE BOILER COMPONENTS according
to manufacturer’s instructions. Generally, this
involves burner and circulator.
9. CHECK SAFETY VALVE at the start of each
heating season and once or twice during the season
to be sure it is in working condition. To do this, fasten
wire or cord to the lever of the valve and pull the lever
standing a safe distance away from the valve.