Burnham V7 SERIES manual Float Type LOW Water CUT-OFF

d.Dismount the low water cutoff 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 (H2PO4).

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 cutoff 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 N.).

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 cutoff check out procedure in step L.4..

2.FLOAT TYPE LOW WATER CUT-OFF

During the heating season, if an 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 float for evidence of collapse and check mercury bulb (where applicable) for mercury separation or discoloration. Do not attempt to repair mechanisms in the field. Complete replacement mechanisms, including necessary gaskets and installation instructions are available from the manufacturer.

N.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 BLOWOFF connection, see Figure 4.

i. Drain boiler until 1” of water is visible in gauge glass. Run temporary 1½” pipe line from the surface blowoff 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.

NOTICE

Check with local authorities or consult local water treatment services for acceptable chemical cleaning compounds.

iii. Start burner and operate sufficiently to boil the water without producing steam pressure. Boil for about 5 hours. Open boiler feed pipe sufficiently to permit a steady trickle of water from the surface blowoff pipe.

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