Installation

Overview

The adhesive oven utilizes waste heat from the engine via heater hose connections to the engine cooling system. The oven may be installed anywhere it is convenient to access for the installer. In order to obtain the full benefit of its capabilities, it must be mounted in the supplied cooler or a similar enclosure, which retains heat and allows for preheating of adhesive stored in the cooler. This results in warm up times as short as 30 minutes after being transferred into the Hydrotherm oven heating tubes. Also, the cooler will maintain adhesive at application temperature for approximately 25 minutes after engine shut off and makes a convenient hot box for warming up trim prior to installation.

Operation

WARNING! The Hydrotherm oven is in operation any time the engine is running. This oven circulates hot coolant under pressure from the engine and operates at approximately 200o F. When opening the lid of the cooler, the operator MUST NOT put his/her hands or face over the cooler. Always wear gloves!

Adhesive should be loaded into the oven tubes with the nozzle end up. The cooler is tall enough to allow partially used cartridges of adhesive to be returned to the oven with nozzles attached for use on the next job. Additional adhesive should be placed in the cooler adjacent to the Hydrotherm oven for preheating. When a cartridge of adhesive is moved into the Hydrotherm oven, the remaining ones in the cooler should be moved closer to the oven and new (cold) adhesive cartridges placed into the cooler near the outside walls to start their preheat.

At the end of the workday, it is recommended that the lid of the cooler be opened to allow the adhesive to cool as rapidly as possible. In this manner, unused adhesive will not exceed its pot life as quickly.

Maintenance

Periodically, examine the system to be sure there are no coolant leaks from the hoses or connections. Check all hose clamps to be sure that they are tight.

If the oven is equipped with a thermostat housing attached by a large hose clamp, the thermostat is field replaceable. Complete procedures are supplied with the replacement thermostat. Contact Pragmatech, Inc. at (877) 244-3961 for replacement parts.

Important! The service life of the thermostat and rubber in the field replaceable housing is three years. It must be replaced after being in use for this length of time.

Installation Overview

The oven has a definite inlet and outlet and must be properly connected to the cab interior heater supply and return hoses. The outlet is labeled and is the fitting on the large thermostat housing which projects from the side of the oven. There is a bleeder screw located on the top of the oven for the purpose of removing air from the unit after installation. See Figure 3 for an overview of the oven connections to the engine cooling system.

Find a location for the oven and cooler where it will be readily accessible to the installer and also allow access from below the vehicle for the heater hoses. Drill 9/64" pilot holes and place two screws with washers through the bottom of the cooler and floor of the service vehicle to hold it in place.
Locate and drill two 7/8” holes below the oven inlet and outlet fittings through the bottom of the cooler and vehicle floor for the heater hoses to connect to the oven. (See Figure 3)
Cut two short pieces of heater hose and place them on the straight end of the through-floor pipes. Insert the pipes through the holes in the cooler bottom with the hose sections inside the cooler. Place the Hydrotherm oven in the cooler above the hose couplings and anchor it to the vehicle using self-tapping screws through the base. Connect the hoses to the oven inlet & outlet fittings and secure the connections with hose clamps.
Run the heater hoses from the engine compartment to the through-floor tubes under the vehicle. Take care to insulate the supply hose and to support and protect the hoses along the undercarriage. Be sure to protect the hoses from the heat of the engine and exhaust system.
Drain the antifreeze from the engine or pinch off the heater supply and return hoses on the engine. Cut the hoses and install the Y fittings. Orient the Y fittings with the coolant flow as shown in Figure 2. Fill the adhesive oven with 50/50 antifreeze mix using a funnel placed into the return hose until antifreeze runs out of the supply hose. Connect the supply and return hoses to the appropriate Y fittings. Check that all hose clamps are tight, run the engine, bleed air from the oven, and check for leaks.

Materials Required

Qty.	Item
1*	Adhesive Oven
1*	Cooler (approx. 30 qt.) to serve as Adhesive Oven housing.
12*	Hose clamps
20’ (approx.)	5/8” Heater hose
2*	Heater Hose Y fittings.
4*	2” Galvanized self threading screws
2*	Fender washers
2 Pcs*	5/8” OD through-floor connection tubes
9’*	Foam pipe insulation for supply heater hose
1	2’ x 3” Galvanized vent pipe ( optional, see text )
1 gal. (approx.)	50/50 ethylene glycol antifreeze mixture
Misc.	Cable ties*, Plumber hanger strap metal, self tapping screws

(*Denotes items supplied with the Hydrotherm oven )

Detailed Installation Procedures

The following step-by-step procedures describe the installation of the Hydrotherm oven. To achieve the full performance benefit of the oven as well as minimum heating time, the adhesive oven must be mounted in the cooler provided. If space absolutely does not permit the use of a cooler, the oven may be installed without one, however the adhesive will cool more quickly after the engine is shut off. Please refer to Figure 1 for a cross section of a typical installation.

Find a convenient location for the supplied cooler in the service vehicle with access to the hose connection points from underneath the truck. The Hydrotherm oven may be positioned anywhere within the cooler. Be sure to position the cooler so that the lid will open fully and stay open by itself. In most van installations, the cooler is located just to the left of the side door, in front of the RR wheel well. It may be located anywhere in the service vehicle that is convenient for the installer.
Position and anchor the cooler to the floor of the van with two of the provided screws and fender washers located such that they will not interfere with the heater hose holes to be drilled. Be sure to drill 9/64" pilot holes and put the large, fender washers under the heads of the screws so they don’t pull through the bottom of the cooler. OPTIONAL: Place a bead of sealant on the outside of the cooler around the perimeter of the bottom. In the event of a coolant leak or when removing the oven to transfer it to another vehicle, this sealant will keep the coolant from running out onto the floor of the service vehicle and it will flow out of the vehicle onto the ground through the two holes drilled for the through floor copper connectors. Any available sealant should suffice for this purpose. It could be a bead of urethane glass adhesive, silicone rubber, or household exterior caulking compound.
Position the Hydrotherm oven in the cooler and mark the hose locations on the bottom of the cooler as shown in Figure 3. Use a 7/8” hole saw to bore holes completely through the cooler and floor of the van. Spray the metal edges of the holes in the van floor with undercoating to retard rusting. Remove any plastic caps from the oven inlet/outlet fittings.
Cut two pieces of 5/8” heater hose, 2.75 and 5.5 inches long. Push 1 inch of each hose onto the long leg of the through-floor copper connector pipes and fasten each one with a hose clamp. Insert the two through-floor copper pipes into the holes in the bottom of the cooler so that the short pieces of heater hose are resting on the bottom of the cooler. The pipe with the short hose should be under the oven outlet fitting. Slide an additional clamp over each hose.
Put the adhesive oven in the cooler with the inlet and outlet tubes above the hoses. Lubricate the hoses with soapy water or antifreeze mixture then pull the hoses up 1 inch onto the oven inlet & outlet fittings. Rotate the through-floor pipes so that they are pointing in the correct direction underneath the vehicle then tighten the loose hose clamps on the oven. Drill 9/64" pilot holes and anchor the oven to the van floor with self-threading screws through the holes in the oven flanges.
Install heater hose from the engine compartment to the through-floor connector tubes below the vehicle and connect them with hose clamps. The supply hose should be insulated with the foam pipe insulation provided. Every effort should be made to keep the hoses above the bottom of the vehicle frame rails for protection. Be sure the hose is adequately supported so that it won’t sag when hot. If the hose must run close to the exhaust system, wrap it with multiple layers of heavy duty aluminum foil or protect it with a galvanized metal heat shield. (Tip: Where the hoses must run for a length along the frame, or close to the exhaust system, they are easily supported and protected by enclosing them in a length of 3” galvanized vent pipe of the type used for residential water heaters.)
Locate the cab heater supply and return hoses in the engine compartment and determine where the Y fittings will be spliced into the existing lines. Refer to the procedure at the end of this manual to determine which is the heater supply hose from the engine. IMPORTANT: Check the hoses for the existence of a control valve. If a valve exists, be certain to install the Y fitting on the engine side of the control valve so that flow through the adhesive oven will be continuous at all times.
Drain the engine coolant into a pan from the lower radiator petcock or use two locking, needle nose pliers to pinch off the heater hose on either side of the place where it will be cut. Cut the engine heater hoses where the Y fittings will be placed and install the Y fittings in the existing hoses. IMPORTANT:On both lines, the exposed leg of the Y should point away from the engine as shown in Figure 2. Tighten the clamps on the engine heater hoses.
Remove the bleeder screw from the oven. Insert a funnel into either the oven supply or return hose in the engine compartment and pour in the proper mixture of antifreeze/water (as recommended by the vehicle manufacturer) until it runs out the bleeder screw hole. Reinstall the screw, then add more coolant until it runs out the other hose.
Connect the oven hoses to the proper Y fittings in the heater hoses and tighten the clamps.
Start the engine. Wait for the engine to warm up and check for leaks. CAUTION: Wear gloves and be careful not to allow any skin to contact the oven or hot antifreeze.
For the first few days after installation, recheck all hose clamps for tightness and loosen the bleeder screw again to be sure that no air remains in the oven. CAUTION: Perform this check when the system is cold before starting the vehicle in the morning.

This completes the Hydrotherm oven installation.

Troubleshooting

If the oven fails to become hot after the engine has run for a while, perform the following checks to ensure proper operation.

Check for air trapped in the system. Open the oven bleeder screw to vent any remaining air. Check the high spots in the hose, especially at the Y connectors or where the original hoses attach to the vehicle cab heater. Loosen the hose clamps and partially disconnect the hose from the fitting to bleed any air at these points.
Be sure the engine is running at the proper temperature. If the engine thermostat has failed and the engine doesn't thoroughly warm up, then the oven will not achieve proper temperature.
Be sure that the Y connectors are located on the engine side of any factory shut off valve that may be located in the original heater hose.
Be sure that the pipe insulation has been placed on the oven supply hose.

Appendix A. -- Locating heater supply hose from the engine

The following methods can be used to identify the supply (discharge) heater hose on the engine.

If at all possible, CHEAT! Find a service manual for the vehicle. The heater hose locations and identification as to supply and return are usually given in the manual. The manual will also identify the location of a control valve in the supply hose, if one exists.
If no manual is available, trace the heater hoses back to the engine and observe where they are attached. The supply hose is usually connected to the top of the engine, often near the point where the upper radiator hose is connected. The return hose is usually connected toward the bottom of the engine, often directly into the coolant pump. On some vans, the return hose is connected directly to a fitting on the radiator.
Another method of hose identification is to start the engine cold with the heater blower on high speed and the temperature lever set to maximum. As the engine starts to warm up, hold onto each hose with a bare hand. The warmest hose is the supply.
This last method will require an assistant. With a cold engine, cut one of the hoses and hold both ends over a small pan. Have the assistant crank the engine over and shut it off the instant it starts. Observe from which hose end the coolant is pumping out. If it came from the hose segment that is attached to the engine, the hose that was cut is the supply hose. If it came from the hose segment that is attached to the heater, it is the return hose.

Appendix B. -- Transferring the Hydrotherm oven to another vehicle

The Hydrotherm oven will outlast most service vehicles and may be easily transferred to a new one. The easiest method of removing the Hydrotherm oven from a vehicle is to disconnect the oven and leave the supply and return hoses in place. This is done with the following procedure:

Obtain two 5/8” hose plugs or make them out of two short pieces of 5/8” OD (1/2” trade size) copper or CPVC pipe with caps on the ends.
Underneath the vehicle, near the location where the hoses are attached to the through-floor pipes, pinch the hoses with locking pliers or C-clamps. Disconnect the hoses from the through-floor connector pipes, insert the plugs and secure them with hose clamps. Then remove the oven, secure the plugged ends of the hoses, and leave the old supply/return hoses in place.
If the oven is equipped with a thermostat housing attached to the oven body with a hose clamp, the thermostat and rubber coupling or thermostat boot must be replaced. Replacement parts are available from Pragmatech, Inc. If the oven is equipped with a metal thermostat housing, it should be returned to Pragmatech, Inc. to have the thermostat replaced.
Install the Hydrotherm oven in the new vehicle according to the procedure detailed previously.

NOTE: A vehicle transfer kit, available from Pragmatech, contains all the materials required for a transfer installation. Call toll free (877) 244-3961 for more information.

Questions or Problems? Call toll free: (877) 244-3961