Alternate Heating WOOD GUN Super E210, Инструкция по установке и эксплуатации

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B low a pH of 5.0 th wat r is acidic nough to
dissolv th st l boil r plat s. Und r th s
conditions th st l gradually b com s thinn r and
thinn r until it is d stroy d. At a pH b tw n 5.0 and
9.0 pittaing of st l plat s is lik ly to occur at a rat
d p nd nt upon th amount of dissolv d oxyg n in
th boil r.
Dissolved Oxygen
A ration of city wat r supply is fr qu ntly us d to
r mov noxious gas s, how v r, a ration r sults in
saturation of th wat r with oxyg n. A majority of
corrosion probl ms ar dir ctly r lat d to th
quantity of dissolv d oxyg n in th boil r wat r.
Elimination of th corrosiv ff ct of dissolv d
oxyg n can b accomplish d ith r dir ctly or
ch mically.
Dir ct or m chanical r moval of dissolv d oxyg n
is don through th us of a d -a rator. Ch mical d -
a ration is don through th introduction of sp cifiec
ch micals in th boil r to r act with th oxyg n. The
dissolv d oxyg n cont nt should b maintain d at a
minimum but at no tim should it xc d 0.007 mg/l.
Sodium sulfiet is commonly us d for th ch mical
r moval of dissolv d oxyg n within th boil r wat r.
To assur th rapid and compl t r moval of th
oxyg n nt ring th boil r f d wat r syst m th
conc ntration of sulfiet in th boil r should b
maintain d at a minimum of 120 ppm.
Solids (Primarily for Steam Boilers)
High boil r solids will l ad to foaming, priming,
surging, carry ov r or boil r sludg in st am boil rs.
Occasional blow downs of th boil r may r m dy
th s conditions. W r comm nd you utiliz th
s rvic s of a local prof ssional plumbing s rvic for
this boil r maint nanc task.
Solids can b cat goriz d as ith r susp nd d or
dissolv d. Susp nd d solids ar thos that can b
r mov d by fieltration whil dissolv d solids ar in
solution with th wat r.
The b st way to d t rmin th dissolv d solid
cont nt of boil r wat r is a conductanc t st. The
conductanc of boil r wat r vari s proportionat ly
with th amount of various ioniz d solids pr s nt.
Anoth r way to d t rmin th dissolv d solids
cont nt is to m asur th chlorid s pr s nt in th
boil r wat r. The chlorid t st is l ss s nsitiv than
th conductanc t st for m asuring small
conc ntrations of dissolv d solids. The r sults of both
t sts should b av rag d for accuracy.
Alkalinity
The alkalinity of boil r wat r should b
sufficci ntly high to prot ct boil r st l against acidic
corrosion, but not so high as to caus carryov r
(basic) corrosion. A minimum valu for alkalinity for
ad quat prot ction is 200 ppm CaCO3.
High boil r alkalinity (in xc ss of 700 ppm
CaCO3) should b avoid d. Valu s high r than this
can caus th st l to b com brittal .
Phosphates
Phosphat s ar us d to count ract hardn ss in th
boil r wat r. It is important to maintain a pH of at
l ast 9.5 to not hind r th r action of th phosphat s
with calcium hardn ss. Try to k p th conc ntration
of phosphat s in th wat r to 30-50 ppm to nabl
compl t r action.
Hardness
The hardn ss of wat r is caus d by calcium and
magn sium ions. Wat r hardn ss will vary gr atly
throughout th country d p nding on th sourc of
th wat r. In boil rs, hard wat r can caus th
formation of scal and sludg or mud. Total hardn ss
should not xc d 50 ppm.
Oils
Ev ry ff ort should b mad to pr v nt oils from
g ttaing into th boil r wat r. Oil caus s foaming or
combin s with susp nd d solids to form a sludg ,
which can caus th ov rh ating of boil r plat s. If
oil do s g t into th boil r, th boil r should
imm diat ly b tak n out of s rvic and thoroughly
cl an d.
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