Carel heaterSteam UR Series, User Manual

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14
ENG
“heaterSteam” +0300075EN - rel. 1.2 - 29.09.2015
2.1 Supply water
The supply water for the electric resistance humidifi er must not be
corrosive, must not emit bad odours, and must not contain too much
lime to avoid excessive deposits. The water, supplied from mains
of drinking water or demineralised water, must have the following
characteristics:
LIMIT VALUES FOR THE RESISTANCE HUMIDIFIERS WATERS
Resistances
Non-coated
Covered
with anti-ad-
hesive fi lm
Min Max Min Max
Specifi c conductivity at 20°C
/68°fH
σ20 - μS/cm 20 1500 1 1500
Total dissolved solids TDS – mg/l (1) (1) (1) (1)
Fixed residual at 180°C/ 356°fH TDS – mg/l (1) (1) (1) (1)
Hydrogen ion activity pH 6.5 8 6 8.5
Total hardness
TH– mg/l
CaCO3
0 (2) 400 0 400
Temporary hardness mg/l CaCO3 0 (3) 30 0 300
Chlorides ppm Cl = 20 = 50(4)
Iron + Manganese mg/l Fe+Mn = 0.2 = 0.2
Silica mg/l SIO2 = 20 = 20
Residual Chlorine mg/l Cl- = 0.2 = 0.2
Calcium sulphate mg/l CaSO4 = 100 = 100
Metallic impurities mg/l 0 0 0 0
Solvents, diluents, detergents,
lubricants
mg/l 0 0 0 0
Tab. 2.a
(1) Values depending on the specifi c conductivity; in general: TDS ≈0,93 * σR, 20
°C; R180 ≈0,65 * σR , 20 °C;
(2) Not lower than 200% the content of chloride in mg/l Cl- ;
(3) Not lower than 300% the content of chloride in mg/l Cl- ;
(4) It could be necessary to intervene on the drain rate to avoid a concentration
in the boiling water higher than 300 mg/l Cl-.
Attention: treating the water with water softeners or
polyphosphates dispensers is not allowed; it allows for reduced
maintenance but favors the concentration of dissolved salts in the
water in the cylinder, leading to potential corrosion to the heating
elements and possible operation irregularities due to the formation of
foam. Should this be impossible to avoid, it requires dilution with
ordinary mains water in such a quantity as to guarantee at least 60% of
its initial hardness value, and not less than 5°f. Water treatment with
reverse osmosis demineralisers is allowed.
Not recommended:
1. the use of well water, industrial water or water from cooling circuits
and, in general, water which may be chemically or bacteriologically
contaminated;
2. the addition to the water of disinfectants or anticorrosion
compounds, as these may cause irritation.
Note :
no relationship can be proven between water hardness
and conductivity; nonetheless, as an indication only, water with a
hardness of 40°f should have a conductivity of approximately 900-1000
mS/cm a 20 °C.
2.2 Drain water
•
contains the same substances dissolved in the supply water, but in
larger amounts;
•
it can reach a temperature of 100 °C (212° F);
•
it is not toxic and can be drained in the white waters collection
system.
•
for drain tempering versions, water temperature will be 60 °C (140 deg
F), so long as the temperature of the feed water is equal to or less than
25 °C (77 deg F) guaranteed.
Attention: completely demineralised water is aggressive. For
connection to a water system with fully demineralized water use
only installation items made of plastic resistant to chemicals (eg.
Polypropylene) or stainless steel.