Carrier 30HW018-040, 30HL050, 060 SERVICING COOLER 30HK,HL ONLY, Tightening Cooler Head Bolts

SERVICING COOLER (30HK,HL ONLY)

NOTE: The cooler on 30HW units is not serviceable.

When cooler heads and partition plates are removed, tube sheets are exposed showing tube ends as shown in Fig. 23.

Four tubes in the bundle are secured inside cooler at baffles and cannot be removed. These are identi®ed on the tube sheets by a drill mark horizontally adjacent to each of the 4 tubes. See Fig. 23. If leakage occurs in any of these tubes, plug as described in Tube Plugging section below.

Tube Plugging Ð Leaky tube(s) can be plugged until retubing can be done. The number of plugged tubes deter- mines how soon the cooler must be retubed. If several tubes require plugging, check with your local Carrier representa- tive to ®nd out how number and location will affect unit capacity.

Figure 24 shows an Elliott tube plug and a cross-sectional view of a plug in place. Table 13 lists the components for plugging.

Use extreme care when installing plugs to prevent dam- aging the tube sheet sections between holes.

Clean parts with Locquic ``N'' solution (or equivalent) and apply a few drops of Loctite No. 675 sealant (or equivalent) to obtain a tight seal without using too much force to set the pin.

Usually plugs can be removed by heating the projecting end of pin to approximately 1000 F (538 C) and chilling quickly with water. Apply heating ¯ame to side of the pin to prevent overheating tube sheet.

RETUBING (See Table 13) Ð When retubing is to be done, obtain the service of quali®ed personnel experienced in boiler maintenance and repair. Most standard procedures can be fol- lowed when retubing the 10HA coolers. A 6% crush is rec- ommended 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.-lb (780 to 815 N-m).

* *

* *

*Four ®xed tubes (cannot be removed) identi®ed by adjacent drill points.

Fig. 23 Ð Typical Tube Sheet

The following Elliott Co. tube rolling tools are required: B3400 Expander Assembly

B3401 Cage

B3405 Mandrel

B3408 Rolls

Place one drop of Loctite No. 675 sealant (or equivalent) on top of the tube prior to rolling.

Tube information:

		in.	mm
·	Tube sheet hole diameter	0.631	16.03
· Tube OD		0.625	15.87
·	Tube ID after rolling	0.581	14.76
	(includes expansion due	to	to
	to clearance)	0.588	14.94

IMPORTANT: Tubes next to gasket webs must be flush with tube sheet (both ends).

Tightening Cooler Head Bolts

GASKET PREPARATION Ð When reassembling, use new gaskets. Compressed non-asbestos/neoprene gaskets (Carrier Material Speci®cation ZA00-32) are to be momen- tarily dipped in compressor break-in oil prior to assembly. Do not soak gaskets in oil, as gasket deterioration results. Use dipped gaskets within 30 minutes to prevent deteriora- tion.

BOLT TORQUES Ð Apply the following torques during bolt tightening sequence described below:

5¤8-in. 16-mm) diameter ¯ange

bolts . . . . . . . . . . . . . 150 to 170 ft-lb (203 to 230 N-m)

1¤2-in. (13-mm) diameter center-stud

nuts . . . . . . . . . . . . . . . . 70 to 90 ft-lb (95 to 122 N-m)

Bolt Tightening Sequence (Fig. 25) Ð The recommended bolt tightening sequence is:

Step 1 Ð Tighten all 5¤8-in. (16-mm) ¯ange bolts and 1¤2-in. (13-mm) center nuts ®nger tight.

Step 2 Ð Following sequence shown in Fig. 25, tighten the bolts and nuts to approximately 50% of speci®ed torque.

Step 3 Ð Starting at top (12 o'clock) tighten ¯ange bolts to speci®ed torque (see Bolt Torques section on this page) con- secutively in a clockwise direction.

Step 4 Ð Tighten center nuts to speci®ed torque.

Step 5 Ð No less than one hour later, retighten center nuts.

Step 6 Ð After refrigerant is restored to cooler, check center studs and exposed gasket edges for refrigerant leaks with soap solution or a Halide device.

Table 13 Ð Plugs and Tubes

COMPONENTS FOR	PART NUMBER
PLUGGING
For Tubes
Brass Pin	853103-500*
Brass Ring	853002-570*
For Holes without Tubes
Brass Pin	853103-1*
Brass Ring	853002-631*
Loctite	No. 675²
Locquic	``N''²

*Order directly from Elliott Tube Co., Dayton, Ohio. ²Can be obtained locally.

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