Appendix, Inside air contamination – Raypak 302B-902B User Manual

Page 53

APPENDIX

Inside Air Contamination

All heaters experience some condensation during

start-up. The condensate from flue gas is acidic.

Combustion air can be contaminated by certain vapors

in the air which raise the acidity of the condensate.

Higher acidity levels attack many materials including

stainless steel, which is commonly used in high effi-

ciency systems. The heater can be supplied with

corrosion-resistant, non-metallic intake air vent materi-

al. You may, however, choose to use outside

combustion air for one or more of these reasons:

1. Installation is in an area containing contaminants

listed below which will induce acidic condensation.

2. You want to reduce infiltration into your building

through openings around windows and doors.

3. You are using AL29-4C stainless steel vent pipe,

which is more corrosion-resistant than standard

metallic vent pipe. In extremely contaminated ar-

eas, this may also experience deterioration.

Products causing contaminated combustion air:

•

spray cans containing chloro/fluorocarbons

•

permanent wave solutions

•

chlorinated waxes/cleaners

•

chlorine-based swimming pool chemicals

•

calcium chloride used for thawing

•

sodium chloride used for water softening

•

refrigerant leaks

•

paint or varnish removers

•

hydrochloric acid/muriatic acid

•

cements and glues

•

antistatic fabric softeners used in clothes dryers

•

chloride-type bleaches, detergents, and cleaning

solvents found in household laundry rooms

•

adhesives used to fasten building products

•