Setting The Regulation And Safety Devices; Setting The Pressostatic Valve (Optional On Chilled Water Cooled Models Only); Setting The Air Flow Sensor - Trane MERCURY EDAB 1105A Technical Manual

Setting the regulation and safety devices

After starting up the unit, set the following set points (see
the microprocessor control manual):
• Room temperature (cooling and heating set point);
• Re l a t i ve ro o m h u m i d i t y ( h u m i d i f i c a t i o n a n d
dehumidification set point);
• Dirty filter differential pressure switch: see paragraph
«Setting the dirty filter sensor».
The settings of the safety devices must not be modified.
R410A
Code Description
AP1-AP2 High pressure switch
First emergency
TSR
safety thermostat
Second emergency
TSRA
safety thermostat
VS Safety valve
Maximum and minimum water temperatures
The maximum and minimum water temperatures for chilled
water circuits and for hot water re-heat circuits are: 5°C ÷
90°C.
The accepted maximum amount of ethylene glycol is
50%.
Setting the pressostatic valve (optional on
chilled water cooled models only)
The pressostatic valve, by controlling the water flow, prevents
the condensing pressure falling too low and at the same
time minimises water consumption. When necessary, set
the pressostatic valve by turning the regulation knob (the
pressure increases when turning it clockwise) until the
condensation pressure stabilizes to recommended* checking
the pressure with a gauge fitted to the pressure tapping of
the compressor discharge valve.
* R410A : pressure 26 bar = temperature 45°C
34
Opening Model Re-set
40,5 bar Manual
All
(opening) Reset
310 °C Manual
All
(opening) Reset
328 °C Manual
All
(opening) Reset
45 bar All -

Setting the air flow sensor

The FS differential pressure switch intervenes if the fan (or
one of the fans) stops working.
The factory set point of the FS differential pressure switch is
at 0.8 mbar (= 80 Pa).
As the difference in pressure between the suction and
discharge of the fans depends on the air flow, it may be
necessary to calibrate the instruments after installation,
checking that the contact closes when the fans are in
operation.
To set the FS pressure switch, carry out the following
procedure:
• simulate a fan fault by stopping a fan; check that the
pressure switch intervenes;
• if the pressure switch does not intervene, gradually
increase the setting until the pressure switch switches
off:
- using an adjustment screw, set the differential pressure
switch on a scale (from 0.8 to 4.0 mbar - from 80 to
400 Pa).
PKG-SVX19B-E4