1 3
TNR-I&S-02
WARNING
DO NOT
attempt to start this water heater until vent pipe solvent
fumes completely clear from the room and inside the vent piping.
VENT PIPE PREPARATION
INITIAL PREPARATION
1. Make sure the solvent cement you are planning to use is designed for
the specific application you are attempting.
2. Know the physical and chemical characteristics and limitations of the
PVC, PVC cellular core or CPVC piping materials that you are
about to use.
3. Know the reputation of your pipe and cement manufacturer and their
products.
4. Know your own qualifications or those of your contractor. The solvent
welding technique of joining PVC, PVC cellular core or CPVC pipe is a
specialized skill just as any other pipe fitting technique.
5. Closely supervise the installation and inspect the finished job before
start-up.
6. Contact the manufacturer, supplier, or competent consulting agency if
you have any questions about the application or installation of PVC,
PVC cellular core or CPVC pipe.
7. Take the time and effort to do a professional job. Shortcuts will only
cause you problems and delays in start-up. The majority of failures in
these systems are the result of shortcuts and/or improper joining
techniques.
SELECTION OF MATERIALS
PRIMER
– It is recommended that Tetrahydrofuran (THF) be used to
prepare the surfaces of pipe and fittings for solvent welding.
DO NOT
use
water, rags, gasoline or any other substitutes for cleaning PVC cellular core
or CPVC surfaces. A chemical cleaner such as MEK may be used.
CEMENT
– The cement should be a bodied cement of approximately 500
to 1600 centipoises viscosity containing 10-20% (by weight) virgin PVC
material solvated with tetrahydrofuran (THF). Small quantities of
dimethylformamide (DMF) may be included to act as a retarding agent to
extend curing time. Select the proper cement; Schedule 40 cement should
be used for Schedule 40 pipe. Never use all-purpose cements or commercial
glues and adhesives to join PVC or CPVC pipe and fittings.
SAFETY PRECAUTION:
PRIMERS AND CEMENTS ARE EXTREMELY
FLAMMABLE AND MUST NOT BE STORED OR USED NEAR HEAT OR OPEN
FLAME. ALSO, USE ONLY IN A WELL VENTILATED AREA.
Figure 21 Concentric Vent Side Wall Attachment
