11
6. Thermistor setting work
Caution:
The heating water tempe rature monitoring T hermistor (T H1H) must make ve ry good contact with either the water piping or
the cylinder containing the wate r to be heated. The insulation pro vided should be used to ensure that the thermistor
reads the correct temperatu re w ithout any heat loss.
6.1. Hot water thermistor TH1H
Locate the thermistor on the water pipe or water cylinder at the point at which the water temperature is to be monitored. Turn the lead wire of the thermistor
downward, and wind the adhesive insulation provided around the thermistor.
Tighten the thermistor in position using the supplied tie band. Fold the lead wire of the thermistor at the bottom, and fix it with the insulation
material using the tie band as shown in figure
[Fig. 6.0.1] (P.2)
6.1.1 Heat Pump system with Under Floor Heating and DX Fan Coil Cooling
•
The outlet water temperature supplied from the unit to the under floor heating will be 45
o
C degrees. The water temperature thermistor should be
located on the return water pipe to the unit.
•
Setting the desired return water temperature is performed on commissioning and is explained in section 7.3.
•
When the under floor heating requires heating, a volt free contact (closed / short circuit) is required on Terminal Block A1 and A2 on the PQFY
Control Panel. This is the same control as a 3 wire adaptor.
•
The TH1H sensor should be attached to the return water pipe on the PQFY to avoid cycling the unit on and off unnecessarily.
•
The design flow temperature of the PQFY is 45
o
C degrees; the return temperature will be designed depending on the flow rate of the water
typically 30 to 35
o
C degrees.
•
On commissioning, the desired water return flow temperature should be set on the controller. Please see section 7.3, commissioning for details
setting the desired water set point.
[Fig. 6.1.1] (P.3)
Note:
THE ROOM TEMPERATURE MUST BE THERMOSTATICALLY CONTROLLED BY THE UNDER FLOOR SYSTEM. THE PQFY WILL PROVIDE
HOT WATER AT 45 DEGREES UNTIL SIGNALED TO DO OTHERWISE.
THERE IS NO ROOM TEMPERATURE CONTROL ON THE PQFY.
Note: Water pumps are not supplied by Mitsubishi Electric
.
6.1.2 Heat Pump system with Domestic Hot Water
The system should be set up as shown in Figure 6.1.2 with the TH1H strapped to the cylinder or inserted into a pocket in the water cylinder. The
desired temperature normally the hottest, 45 Degrees equals 28 degrees on the PAR 21 remote controller.
•
The Par 21 should be set to Heating 28 Degrees to achieve a hot water temperature of 45 degrees.
•
For further control of Immersion heaters please see the product ACH1.
NOTE , Stagnant hot water should not be stored at 45degrees due to risk of Legionella,
NOTE If a direct cylinder is used in conjunction with a Plate heat exchanger with brass pump, the TH1H water temperature thermistor should be
strapped to the cylinder water pipe connecting to the inlet to the plate heat exchanger.
6.1.3 Heat Pump system with a Swimming Pool
•
The outlet water temperature supplied to the swimming pool from the unit will be 45
o
C degrees. The TH1 water temperature thermistor should be
located on the return water pipe from the swimming pool i.e. the actual swimming pool water temperature.
•
Setting the desired return water temperature is performed on commissioning and is explained in section 10.
•
When the swimming pool requires heating, a volt free contact (Closed / Short Circuit) is required on Terminal Block A1 and A2 on the PQFY
Control Panel. This is the same control as a 3 wire adaptor.
•
The TH1H sensor should be attached to the return water pipe from the swimming pool to avoid cycling the unit on and off unnecessarily.
•
The PQFY will heat up the pool until the set temperature, typically until 30
o
C is reached.
•
On commissioning, the controller should be set to heating and the corresponding controller temperature to the desired water temperature. See
section 7.3
for the corresponding controller temperature.
[Fig. 6.1.3] (P.4)