OPTIONAL EQUIPMENT FOR CHROMALOX STEAM BOILERS (cont’d.)
The Sequence Reverser accomplishes its tasks and shows the rela- tive use of each of ten beat stages during the first four days of the cycle. This is how the work load would be distributed on a boiler with- out Sequence Reverser. It can be seen the early stages are ON most of the time and the later stages are OFF most of the time, since they are used only during heat load peaks. (This analysis assumes hours of use directly affecting component life. Frequency of on/off operations has been ignored because of the limited
It is clear, without sequence reversing, the early stages would tend to fail long before the later stages. The sequence reverser essentially equalizes the relative usages of heating stages. It can be seen, without the sequence reverser the first heat stage is used approximately twice as much as it is with the sequence reverser. This means the boiler will be likely to have its first element failure in half the time without
Solid State Progressive Sequencer (See Figure 22)
The solid state progressive sequencer provides accurate electronic control of
PROGRESSIVE SEQUENCING
The solid state sequencer operates on 120 V AC/60 Hz and each output is relay switched with a load rating of 125 VA at 120 VAC.
Figure 21 – Five Step Sequence Reverser
sequence reverser as compared to the boiler with sequence reverser. In addition. boilers without sequence reverser will have many failures spread over a long time while boilers with sequence reversing will require element changes at roughly the same time. (See wiring dia- gram on Page 4).
Figure 22 – Solid State Sequencer
MAINTENANCE
CAUTION: Hazard of electric shock. Disconnect all power before working on boiler.
Chromalox Electric Steam Boilers are designed for years of trou-
1.The use of specific boiler cleaning compounds cannot be recom- mended. We do recommend that a reputable firm of water treat- ment engineers be consulted regarding conditioning boiler water. Proper selection must be made of a compound to prevent damage to copper sheath heating elements.
2.The sight glass should be checked daily to ensure the boiler has adequate water.
3.A monthly inspection should be made of the internal wiring. All electrical connections should be checked for lightness.
4.A check for water or steam leaks should also be made and any loose fittings immediately tightened.
5.If boiler is equipped with a Solid State Auxiliary Low Water Cutoff, every four months the probe should be checked for deposits and cleaned, if necessary. This is accomplished by remov- ing the inspection plate, removing the probe (with a standard sparkplug wrench) cleaning and replacing.
Note: The system will not operate if the boiler is using distilled, demineralized or deionized water.
At the same time, one of the bottom heating elements should be removed. If scale has begun to form, all elements should be cleaned and boiler drained and flushed.
6.IMPORTANT: The Manufacturers' Data Report enclosed within the instruction sheet is very important and must be put in a safe place. You may be called upon to produce it by a State agency.
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