ENGLISH REMOTE AUXILIARY AIR CONDITIONING SYSTEM AND AIR DISTRIBUTION INSTALLATION GUIDELINES For Freightliner Cascadia ISO 9001:2000 L 2653 Rev. 20090130
WARNING: Only trained technicians should perform these checks and tests. These units contain voltage of 12VDC, 24VDC, 115VAC and/or 230VAC. Some of these voltages can be lethal. These units also contain refrigerant under high pressure. Refrigerant circuits should only be accessed by licensed technicians. COPYRIGHT 2009 Dometic Corporation, Environmental Division, All Rights Reserved. No part of this publication may be reproduced, translated, stored in a retrieval system, or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwise without prior written consent by Dometic Corporation, Environmental Division. Every precaution has been taken in the preparation of this manual to insure its accuracy. However, Dometic Corporation, Environmental Division assumes no responsibility for errors and omission. Neither is any liability assumed for damages resulting from the use of this product and information contained herein. 2 ENGLISH
CONTENTS INTRODUCTION 5 LOCATING THE COMPONENTS 6 INSTALLING THE CONTROL/DISPLAY PANEL 7 INSTALLING THE RETURN AIR VENT 8 INSTALLING THE SUPPLY AIR DISTRIBUTION 9 PREPARING THE CHEB FOR INSTALLATION 11 INSTALLING THE CHEB 12 INSTALLING THE CONDENSER 14 ROUTING THE REFRIGERANT LINES AND CONDENSER POWER CABLE 15 ENGLISH 3
4 ENGLISH
INTRODUCTION This document contains supplemental guidelines for installing the Qt-series control and air distribution for the Dometic auxiliary air conditioning system on a Freightliner Cascadia. It is intended to be used in conjunction with the standard installation manual, which covers all other aspects of installing, testing and operating this system. These guidelines that follow represent years of development of parts and procedures to not only make the system perform well, but to also look factoryinstalled. Please be creative in your installation, but keep functionality and safety in mind. Key issues are: evaporator discharge venting, evaporator return air and condenser air flow. Other issues include: controls accessibility, condensate removal or wire and hose chafe protection. Required Tools: Drill motor Hole saws: 1-5/8", 1-7/8", 2-1/2", 3-1/2" (for 10K unit) and 4" Drill bits: 1/8", 5/32", 9/32" Nut drivers: 1/4", 3/8", 15/16" Phillips head screwdriver Open-end wrenches: (2) 7/16", (1 each) 5/16", 13/16" and 3/4" Torque wrench may also be required Do not attempt to install any components until you read and understand the instruction in both manuals. ENGLISH 5
LOCATING THE COMPONENTS The Dometic remote auxiliary air conditioning system consists of two basic components: an outside condensing unit, which contains the condenser and an exhaust fan, and an inside unit, which contains the compressor, heater, evaporator and blower (CHEB). The two units are connected by precharged refrigerant lines with quick-connect fittings. Install the CHEB in the passenger's side luggage compartment of the truck, under the bunk. To make this work, you will have to remove the plastic divider and trim with a hacksaw or reciprocating saw for the ductwork. Use the CHEB template to determine the best place to mount the unit. The Dometic condenser installs either under or behind the sleeper. These installations (and the parts in the kit) are for an installation underneath of the sleeper. If you plan to mount the generator and/or generator radiator underneath the sleeper fairings, we recommend mounting the HVAC condenser on the rear of the sleeper. You will need kit 710035048 for a rear mount installation. Figure 2 Condensing unit mounted under truck IMPORTANT! Refer to the Dometic installation manual for details on installing and connecting the CHEB and condensing unit. Figure 3 Condensing unit mounted on back of sleeper Figure 1 CHEB installed in luggage compartment 6 ENGLISH
INSTALLING THE CONTROL/DISPLAY PANEL Control/Display mounted Passenger's side Driver's side Figure 4 Control/Display mounted Mount the control in such a location as to give the driver good access. The suggested location would be near the current HVAC controls, however that may be very tough on this model. In this particular installation, we mounted the control on the driver s side cabinet. Route the CXP cable through the cabinet, behind the wall, and down into the bunk area, then to the rear center portion of the bunk for later connection. MOUNTING THE POWER LOGIC BOX The Power Logic Box (PLB) will be mounted under the rear, center portion of the bunk, toward the passenger s side of center. Use four #8 x 3/4" screws to mount the bracket to the bunk wall (Fig. 5). ROUTING CABLES The PLB box comes with several different types of cables: Figure 5 PLB mounting location The wires in orange split loom will go toward the CHEB unit. The flexible power cord(s) will go toward the power distribution panel or inverter. The phone cable mounted on the CHEB unit plugs into the hole marked TSEP. The phone cable from the Control/Display plugs into the hole marked Display. All cables should be neatly routed and clipped to prevent chaffing. IMPORTANT! Refer to the Dometic installation manual for details on routing and connecting cables from the Control/Display panel to the PLB and CHEB. Wires enclosed in split loom with large round plug Flexible power cables covered in orange loom Phone type cables ENGLISH 7
INSTALLING THE RETURN AIR VENT No return air vent is needed on this truck. Instead, drill at least 14 2-inch holes through the front bunk bulkhead into the passenger s side closet. This will provide sufficient space for air to flow back to the CHEB. Figure 6 Return air holes cut under passenger's side cabinet Remember, good air flow from the return air grill to the CHEB evaporator coil is critical for your air conditioning system to perform correctly. Do not allow anything to block this air flow. 8 ENGLISH
INSTALLING THE SUPPLY AIR DISTRIBUTION For this installation, we will direct a portion of the air through the factory ductwork. To make this work properly, we will install a flapper valve into the main duct. Cut a hole in the duct large enough for the flapper to operate, while small enough for all the fasteners to catch. Prepare the flapper valve by installing foam around the very edge of the flapper valve. Install the flapper valve into the duct while paying special attention to the direction of the flapper (refer to Figs. 7-10). Mount using the #8 x ½" screws that are included with the kit. Figure 9 Location of fit for flapper valve Figure 7 Main duct (view inside driver's side cabinet) Figure 10 Orientation of flapper valve Figure 8 Flapper valve For installing the supply air vents and ductwork we will use two (7-10k BTU) or three (14k BTU) 4" vents/ducts. One duct will supply the factory vents via the flapper valve (Figs. 7 and 11). One vent will supply the air at the bottom of the bunk (Fig. 12). A third cut routes through the passenger s side cabinet and discharges rearward high onto the bunk (Fig. 13). You can decide to use this as an option when only supplying two vents, when the CHEB does NOT supply heat (i.e., a diesel-fired heater is in use). ENGLISH 9
Figure 11 Ductwork to flapper valve Figure 12 Location of vent at bottom of bunk Figure 13 A discharge vent up running through the passenger's side cabinet 10 ENGLISH
PREPARING THE CHEB FOR INSTALLATION Before you install the CHEB into the truck, you need to make a couple of modifications. First, remove the oval duct connector from the side of the unit. Use a ¼ nut driver for this job. Next, you will need to find the VHR724 or VHR734 plastic plenum provided in the kit. One plenum has two oval duct attachments; the other has three oval duct attachments (Fig. 14). The kit will have only one or the other. Use the provided self-tapping screws to mount the plenum. NOTE: Before installing the CHEB, refer to the Vents and Ductwork section to cut your holes for the return air. Figure 14 Oval duct adapter removed for installation of plenum ENGLISH 11
INSTALLING THE CHEB Install the CHEB in the passenger s side luggage compartment of the truck, under the bunk (Fig. 15). To make this work, you will have to remove the plastic divider and trim out for the ductwork. Use a hacksaw or reciprocating saw for that job later. Locate the CHEB template. Place the template with the Evaporator Coil facing the driver s side of the truck. Leave at least 6 between the back of the CHEB and the rear wall of the bunk. Check location of the exhaust pipe below to make sure it does not interfere with the drain. DO NOT mark for the refrigerant lines to run down directly behind the CHEB (Fig. 16), as they will be on top of the exhaust pipe. Instead, route them over near the PLB and feed through the floor (Fig. 17). Drill through the rubber mat with a 2-½" holesaw (DO NOT DRILL THROUGH THE METAL). Then drill through the metal with a 1-7/8" hole saw. Figure 16 Routing refrigerant lines and cables from CHEB Drill the drain hole with a 1-5/8" hole saw. Install the 1-7/8" grommets (grey) into the two 1-7/8" holes. Push in until they lock in the hole. Use the edge of the unit line to situate one of the mounting brackets for hole marking. Be sure your bracket is located in an area noted by XXXXX, which gives locations available for mounting. Figure 17 Location of the refrigerant line exit Figure 15 Location of the CHEB 12 ENGLISH
Insert the CHEB unit into the truck. Make sure that the drain fitting lines up with the hole. Install the brackets by using one ¼"-20, 2-½" bolt (provided) and one small washer from the top. Secure underneath the truck with one large washer and one nylok nut. Snug all bolts to the point where the bracket just starts to bend, then stop. Prior to installing the refrigerant lines though the grommets or installing the CHEB, you may want to run both the power cord and condenser power cable through the holes. Then insert the refrigerant lines into their respective grommets. Lightly lubricate one side of each coupling with light oil or refrigerant oil. Be sure to get the face and the threads. Hand tighten the quick-connect fittings, making sure they thread up correctly. Tighten with the correct wrenches (13/16", 3/4" and 15/16") to 10-12 ft/lbs. If any hissing is heard during the tightening process, DO NOT STOP TIGHTENING. It is because the fittings are not quite in-line correctly. Keep tightening and the hissing will stop. When complete, fill grommet with silicone or one-part foam to provide a water and airtight seal. Figure 19 Installing the P-trap Install the drain fitting into the bottom of the CHEB from the underside of the truck, finger tighten. Place the hose clamp over the end of the P-trap. Push the end of the P-trap over the drain fitting and tighten the clamp (Fig. 19). Figure 18 Installed CHEB, PLB and refrigerant lines Connect the TSEP (temperature sensor cable) located on CHEB to the PLB. Connect the electrical connectors between the CHEB and PLB (one in the orange split loom). Route and clip to prevent chafing (Fig. 18). ENGLISH 13
INSTALLING THE CONDENSER The Dometic condenser installs either under or behind the sleeper. These installations (and the parts in the kit) are for an installation underneath of the sleeper. If you plan to mount the generator and/or generator radiator underneath the sleeper fairings, we recommend mounting the HVAC condenser on the rear of the sleeper. You will need kit 710035048 for a rear mount installation. Additional instructions are included for a rear-mount installation. The condenser mounts midline of the truck, just behind the transmission (Fig. 20). The condenser adaptor provides for ease of mounting the condenser. First, mount the condenser to the adaptor. Make sure that the refrigerant connections are facing toward the end with four holes in it, which in turn will face toward the rear of the truck. Find the hardware you will need to mount the adaptor: two #10 x 1" self-tappers and four ¼"-20, 1" bolts with washers and nuts. Figure 21 Hooking the adaptor plate over the Z-channel Use the hooks provided on the adaptor to hook over the cab support Z-channel (Fig. 21). At the other end of the adaptor there are two small holes. Use the #10 x 1" self-tappers to drill through these holes for the initial mounting of the adaptor. Once they are secure, use a ¼" drill bit to drill for the four ¼" bolts (Fig. 22). Figure 22 Condenser adapter fastener detail Figure 20 Mounting the condenser adaptor You can also mount this unit on the rear of the cab (Fig. 23). Here is one possible solution. Use of rear cab mount kit 710035048 is recommended. You will normally need a longer refrigerant lineset for this option than what comes in the kit. Figure 23 Condenser mounted on rear of cab 14 ENGLISH
ROUTING THE REFRIGERANT LINES AND CONDENSER POWER CABLE The refrigerant lines will pass over the Z-channels and then back around to the quick-connect. Connect the quick-connects in the manner described previously. With the cushion clamps, secure the refrigerant lines as shown directly to the Z-channel. Use cable ties to secure the refrigerant lines to each other and to the condenser power cable. After connecting the condenser power cable, secure the power cord in such a manner that the connections pull in a linear fashion, not to the side. ENGLISH 15
Dometic Corporation, Environmental Division P.O. Box 15299 I Richmond, VA 23227 USA 804-746-1313 I Fax 804-746-7248 www.dometictruck.com I sales@dometictruck.com UNITED STATES & CANADA SERVICE ONLY Weekdays 8:00 am to 5:00 pm (Eastern Time) 804-746-1313 All other times 888-440-4494 ISO 9001:2000 L 2653 Rev. 20090130 For all other areas visit our website to find your nearest distributor.