U.S. Boiler Company MPO - IQ, Инструкция по эксплуатации

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A. EVALUATE THE ExISTING WATER
SYSTEM.
Design a piping system and install boiler which will prevent
oxygen contamination of boiler water and frequent water
additions.
1. There are many possible causes of oxygen contamination
such as:
a. Addition of excessive make-up water as a result of
system leaks.
b. Absorption through open tanks and fittings.
c. Oxygen permeable materials in the distribution
system.
2. In order to insure long product life, oxygen sources must
be eliminated. This can be accomplished by taking the
following measures:
a. Repairing system leaks to eliminate the need for
addition of make-up water.
b. Eliminating open tanks from the system.
c. Eliminating and/or repairing fittings which allow
oxygen absorption.
d. Use of non-permeable materials in the distribution
system.
e. Isolating the boiler from the system water by installing
a heat exchanger.
WARNING
System supply and return piping must be
connected to correct boiler piping.
U.S. Boiler Company recommends sizing the
system circulator to supply sufficient flow (GPM)
to allow a 20°F temperature differential in the
system. When sizing the system circulator, the
most restrictive single zone should be used to
determine maximum pressure drop.
CAUTION
Maintain minimum ½ inch clearance from hot water
piping to combustible materials.
3. In order to insure long product life, operate boiler at
appropriate flow rate to minimize areas of overheating
.
a. Design system to ensure that the flow is above the
limit called for in Table 4.
b. Maintain a constant boiler pressure of 12 PSI.
IV. WATER BOILER PIPING
NOTICE
Failure to pipe boiler as specified in this manual may result in excessive system noise.
Boiler Model No. Flow Rate (Gal / Min)
MPO-IQ84 4.5
MPO-IQ115 6.0
MPO-IQ147 8.0
MPO-IQ189 10.0
MPO-IQ231 12.0
TABLE 4: MINIMUM FLOW RATE
WARNING
Do not operate boiler below minimum volumetric
flow rates.
B. CONNECT SYSTEM SUPPLY AND RETURN
PIPING TO BOILER. See Figures 13A and 13B. Also,
consult Residential Hydronic Heating Installation and Design
I=B=R Guide.
1. If this boiler is used in connection with refrigeration
systems, the boiler must be installed so that the chilled
medium is piped in parallel with the heating boiler using
appropriate valves to prevent the chilled medium from
entering the boiler. Also, consult Residential Hydronic
Heating Installation and Design I=B=R Guide.
2. If this boiler is connected to heating coils located in air
handling units where they may be exposed to refrigerated
air, the boiler piping must be equipped with flow control
valves to prevent gravity circulation of boiler water during
the operation of the cooling system.
3. If an indirect water heater is used, priority zoning can be
used. Do not use priority zoning for Hydro-Air Systems.
Refer to the Indirect Water Heater Installation, Operating,
and Service Instructions for additional information.
4. The MPO-IQ is designed to withstand thermal shock from
return water temperatures as low as 100°F, but prolonged
return temperatures of below 135°F can cause excessive
flue gas condensation and damage the boiler and/or venting
system.
Use a boiler bypass if the boiler is to be operated in a
system which has a large volume or excessive radiation
where low boiler water temperatures may be encountered
(i.e. converted gravity circulation system, etc.) The bypass
should be the same size as the supply and return lines with
valves located in the bypass and return line as illustrated
in Figures 13A and 13B in order to regulate water flow
for maintenance of higher boiler water temperature.