THERMEx THW100, Руководство по эксплуатации продукта

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Heat Pump Manual
33
CONTROL
On a water to water unit the controller is monitoring the evaporator water. There is an
evaporator water set point and if the evaporator water drops below this then the controller will
open the solenoid valve to prevent freezing of the evaporator. This is typically set at 5C
High Pressure Protection
This setting will open the hot gas valve if this pressure is breached
– it is not designed to stop
the unit from cutting out in the event of a high pressure problem but to prevent nuisance trips.
Putting the unit in standby mode
Using the key pad the unit
can be put into standby
mode if there is a reason to
shut the unit down for a
short amount of time.
·
Scroll through the menu to find
“KEYPAD STANDBY”
·
Press
“OK” and then “OK TO CONFIRM” The unit will stop
running
·
The screen will be showing
“OK TO RE-START” and
“KEYPAD STANDBY MODE” will be flashing
·
Press
“OK” and the heat pump will go through its normal
start up procedure
THIS DOES NOT TURN THE UNIT OFF AND THE ELECTRICAL
CIRCUITRY INSIDE THE ELECTRICAL BOX WILL STILL BE LIVE
High Water Temperature Units – Water Temperature Supply Above 60°C
If the heat pump is to operate about supply water temperatures then the unit needs to be
configured to operate at these temperatures.
The variances to the standard configuration are the unit will be supplied with a plate heat
exchanger condenser and rather than a flow switch the unit will be supplied with a flow meter.
The flow meter is installed to ensure that adequate flow is supplied to the unit across the
condenser.
With heat pumps running at higher temperatures discharge gas temperature and pressure
need to be kept within the performance envelope of the compressor. Therefore to remove the
heat and keep these temperatures down the unit needs higher than normal water flow
through the condenser. To ensure this flow is adequate then the controller will monitor the
flow and shut the unit down if it is not sufficient.
There is a chart earlier on in this document showing the required flows and when
commissioning the unit the flow through the unit can be found by scrolling through the main
menu until
“VIEW FLOWS” is found. If sufficient flow through the unit is not maintained it may
void the warranty on the compressor.
Water to Water Units
The hot water side of a water to water unit operates the same as an air to water unit.
However the heat load provided for the evaporator is a via a water source. This is typically
from the on-site chiller. The chiller is typically providing 7C water for the air conditioning
system and that water is returning to the chiller at 12C and has therefore picked up heat. This
heat is transferred by the heat pump into the hot water system.
It has the added benefit of imparting a cooling load onto the system and reduce the load on
the chillers. However as the evaporator is doing cooling there is a risk of freezing and splitting
the evaporator. This can occur when the heat load drops off suddenly, ice or debris builds up
in the evaporator or the evaporator pump fails.