Carrier 30HL - Cooler Servicing and Repair; Tube Plugging Procedure; Cooler Retubing Process

6. ANY SAFETY DEVICE TRIPS.
if device is low-pressure switch, reset is automatic
and unit restart is thru normal timer cycle. In the
case of low, or lost, refrigerant charge, charge
must be increased to normal level before restart.
If device is one of the following, high-pressure
switch, overtemperature switch or oil pressure
safety switch, press control circuit ON-OFF
switch to OFF, then to ON. Restart occurs thru
normal timer cycle.
If chilled water flow has stopped, locate and
correct cause, restart water flow. Unit will restart
automatically thru normal timer cycle.
Refer also to Troubleshooting section for addi¬
tional information on unit malfunctions.
SERVICING COOLER
When cooler heads and partition plates are
removed, tube sheets are exposed showing tube
ends shown in Fig. 9.
*Four fixed tubes (cannot be removed) identified by adjacent drill
points.
Fig. 9 — Typical Tube Sheet
Tube Plugging — Leaky tube(s) can be plugged
until retubing can be done. The number of plugged
tubes determines how soon cooler must be retubed.
If several tubes require plugging, check with your
local Carrier representative to find out how number
and location will affect unit capacity.
Figure 10 shows an Elliott tube plug and a cross-
sectional view of a plug in place. Table 8 lists the
components for plugging.
CAL I ION: Use extreme care when insiaOmg
plugs to prevent damaging the tube sheet sec¬
tions between holes.
Clean parts with Loequie '‘N” and apply a few
drops of Loctite #75 to obtain a tight seal without
using too much force to set pin.
Usually plugs can be removed by heating pro¬
jecting end of pin to approximately 1000 F and
chilling quickly with water. Apply heating flame to
side of the pin to prevent overheating tube sheet.
^ Table 8 — Plugs and Tubes
UNIT 30HK,HL
015.020 025.030
COMPONENTS FOR j
PART NUMBER
PLuGGINCj
For Tubes I
Brass Pin
853103500*
Brass Ring
853002-570*
For Holes without Tubes i
Brass Pin
1 853103-r
Brass Ring
853002 631*
Loctite (
No, 75t
Loequie 1 ; -'N'-t
*Order directly from Elliott Tube Co.
Dayton, Ohio.
tCan be obtained locally.
Re tubing (See Table 8) — When relubing is to be
done, obtain service of qualified personnel exper¬
ienced in boiler maintenance and repair. Most
standard procedures can be followed when retubing
the lOHA coolers. A 6% crush is recommended
when rolling replacement tubes into the tube sheet.
A 6% crush can be achieved by setting the torque on
the gun at 48 to 50 in. lbs.
The following Elliott Co. tube rolling tools are
required:
B34()() Expander Assembly
B340] Cage
B3405 Mandrel
B3408 Rolls
Place one drop of Loctite No. 67541, or
equivalent, on top of tube prior to rolling.
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