Installation; Maintenance - Danfoss AKS 38 Installation Manual

ENGLISH
Refrigerants
Applicable to HCFC, non flammable HFC and
R717 (Ammonia).
Temperature range
–50°C/+65°C (–58°F/149°F)
Pressure range
AKS 38 is designed for a max. working
pressure of 28 bar g (406 psi g)
IMPORTANT
Should pressure testing in excess
of 28 bar g (406 psi g) be necessary
then the internal float assembly must
be removed, thus allowing a maximum test
pressure of 42 bar g (609 psi g)
Electrical data
- Change-over Micro (SPDT) switch
- 250 V a.c / 10 A
- 30 V d.c / 5 A
- DIN Plug
- DIN 43650 connection
- PG 11, 8-10 mm (0.31" - 0.39")
- Screw terminal 1.5 mm (16 AWG)
2
- 3+PE
Liquid level differential
Variable between 12.5 mm to 50 mm
(½" to 2") in 12.5 mm (½") increments. Required
differential setting should be made prior to

installation.

Factory set at 50 mm (2").
Enclosure
IP 65
Installation
IMPORTANT
AKS 38 must always be installed in
a vertical position (fig. 1 and 2).
AKS 38 is supplied complete with flanges (fig
2, pos. 14). The external surfaces of the flanges
must be prevented against corrosion with a
suitable protective coat after installation.
To avoid an oil seal forming which would affect
the movement of the internal float the bottom
connecting pipe must have an incline towards
the liquid separator.
Shut-off valves should be mounted as close as
possible to the float for service (fig. 1).
Switch point
The switch point is relative to the actual liquid
level marking on the AKS 38 housing. See fig 7.
The upper switch point is actually (D : 2) higher
than the actual liquid level marking.
The lower switch point is actually (D : 2) lower
than the actual liquid level marking.
Where D = differential.
Adjusting the liquid level differential switch
point (see fig. 9)
The float comes factory set with a differential
setting of 50 mm (2") with the lower locking ring
C in position b. To acheive smaller differential
settings reposition the lower locking ring C at
b = 37.5 mm (1½");
1
(b = 25 mm (1"); b = 12.5 mm (½").
2 3
© Danfoss A/S (MWA), 2015-02
The upper locking ring D in position a should
not be adjusted or repositioned.
IMPORTANT
The adjustment must be made
before AKS 38 is installed in the
refrigeration system. Use two thumbs for
repositioning the locking rings. Do not use
any tools.
Remove the AKS 38 switch box (fig. 3, pos. 2).
• Unfasten the M4 × 8 (fig. 3, pos. 3) pinol
tailstock screw with a Allen key.
• Remove the switch box by slowly easing
upwards.
Remove the AKS 38 housing top cover
(fig. 3, pos. 4).
• Unfasten the 4 × M12 × 35 stainless steel
bolts (fig. 3, pos. 5).
• Remove the complete top cover including
installed pressure tube (fig. 3, pos. 7).
Remove the complete float assembly
(fig.3, pos. 1 and fig. 4, pos. 1) from the
AKS 38 housing (fig. 3, pos. 6).
• Reposition the lower locking ring at the
required differential setting.
• See fig. 8 and fig. 9.
Reassembly
• Refit the float assembly back into the
AKS 38 housing (fig. 3, pos. 6).
• Reinstall the complete top cover
(fig. 3, pos. 4) and fasten the 4 × M12 × 35
bolts (fig. 3, pos. 5).
Max. tightening torque: 74 Nm (100 ft-lb).
• Reinstall the switch box (fig. 3, pos. 2) by
slowly forcing it down over the pressure
tube (fig. 3, pos. 7).
• Position the switch box (fig. 3, pos. 2) as
required and fasten the M4 × 8 pinol
tailstock screw (fig. 3, pos. 3) with a Allen
key.
Electrical installation
Make electrical connection to DIN plug using
cable with maximum 4 cores and wire in
accordance with wiring diagram (fig. 8).
1. Common
2. Normally Closed
3. Normally Open
Earth terminal

Maintenance

IMPORTANT
The AKS 38 must be evacuated
before opening to air.
Replacing the internal float assembly
(fig. 3, pos.1)
• Unscrew the stainless steel bolts
4 × M12×35 (fig. 3, pos. 5).
• Remove the top cover (fig. 3, pos. 4)
including installed pressure tube
(fig. 3, pos. 7) and switch box (fig. 3, pos. 2).
• Remove the internal float assembly
(fig 3, pos. 1).
• Install the new float assembly.
DKRCI.PI.GD0.A3.ML / 520H4521
Replacing the flange gaskets
(fig. 2, pos. 15)
• Unscrew the 4 × M12×35 stainless steel
bolts on the side flange (fig. 2, pos. 13).
• Unscrew the 4 × M12×35 stainless steel
bolts on the bottom flange (fig. 2, pos. 13).
• Remove both gaskets (fig. 2, pos. 14).
• Install the new gaskets.
• Fasten 4 × M12×35 stainless steel bolts in
each flange. Max. tightening torque: 74 Nm
(100 ft-lb).
Replacing the top cover gasket
(fig. 3, pos. 8)
• Unscrew the 4 × M12×x35 stainless steel
bolts (fig. 3, pos. 5).
• Remove the top cover (fig. 3, pos. 4)
including installed pressure tube (fig. 3,
pos. 7) and switch box (fig. 3, pos. 2).
• Remove the gasket (fig. 3, pos. 8).
• Install the new gasket.
• Fasten 4 × M12×35 stainless steel
bolts (fig. 3, pos. 5).
Max. tightening torque: 74 Nm (100 ft-lb).
Replacing the aluminium gasket
(fig. 3, pos. 11)
• Unscrew the M4 × 8 pinol tailstock screw
(fig. 3, pos. 3) with a Allen key.
• Remove the switch box (fig. 3, pos. 2) by
slowly easing upwards.
• Unscrew the pressure tube (fig. 3, pos. 7)
with a 32 mm wrench.
• Remove the aluminium gasket
(fig. 3, pos. 11).
• Install the new gasket.
• Reinstall the pressure tube.
• Reinstall the switch box.
Replacing the switchbox (fig. 3, pos 2)
• Remove the DIN-plug (fig. 6).
• Unscrew the M4 × 8 pinol tailstock screw
(fig. 3, pos. 3) with a Allen key.
• Remove the switch box (fig. 3, pos. 2) by
slowly easing upwards.
• Install the new switch box.
Replacing the O-ring at the pressure tube
(fig. 3, pos. 9)
• Unscrew the M4 × 8 pinol tailstock screw
(fig. 3, pos. 3) with a Allen key.
• Remove the switch box (fig. 3, pos. 2) by
slowly easing upwards.
• Remove the O-ring.
• Install the new O-ring.
• Reinstall the switch box.
5