PIPING AND WIRING FOR INDOOR UNIT
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PIPING AND WIRING FOR INDOOR UNIT
Procedures about water piping and electric wiring at the indoor unit are described in this chapter.
Water piping and water circuit connection, water charging, pipe insulations will be shown for
water piping procedures. For wiring, terminal block connection, connecting with the outdoor
unit, electric heater wiring will be introduced. Accessories connection, such as sanitary water
tank, thermostat, 3way or 2way valves, etc will be dealt in separated chapter.
Water Piping and Water Circuit Connection
CAUTION
!
General Considerations
Followings are should be considered before beginning water circuit connection.
- Service space should be secured.
- Water pipes and connections should be cleaned using water.
- Space for installing external water pump should be provided if internal water pump capacity
is not enough for installation field.
- Never connect electric power while proceeding water charging.
Definition of terms are as follow :
- Water piping : Installing pipes where water is flowing inside the pipe.
- Water circuit connecting : Making connection between the product and water pipes or between
pipes and pipes. Connecting valves or elbows are, for example, in this category.
Configuration of water circuit is shown in Chapter 2. All connections should be complied with
presented diagram.
While installing water pipes, followings should be considered :
- While inserting or putting water pipes, close the end of the pipe with pipe cap to avoid dust
entering.
- When cutting or welding the pipe, always be careful that inner section of the pipe should not be
defective. For example, no weldments or no burrs are found inside the pipe.
- Drain piping should be provided in case of water discharge by the operation of the safety valve.
This situation can be happened when the internal pressure is over 3.0 bar and water inside the
indoor unit will be discharged to drain hose.
While connecting water pipes, followings should be considered.
- Pipe fittings (e.g. L-shape elbow, T-shape tee, diameter reducer, etc) should be tightened
strongly to be free from water leakage.
- Connected sections should be leakage-proof treatment by applying teflon tape, rubber bushing,
sealant solution, etc.
- Appropriate tools and tooling methods should be applied to prevent mechanical breakage of the
connections.
- Operation time of flow control valve(e.g. 3way valve or 2way valve) should be less than 90
seconds.
- Drain hose should be connected with drain piping.
- Maximum allowable Torque at the water piping connection is 50 N·m
- Connect the water for filling or refilling the heating system as specified by EN 1717/EN 61770 to
avoid contamination of drinking water by return flow.