
Avoid operation of heater near combustible fluids or in combustible vapor or gas laden atmosphere. 5. Provide adequate space at terminal end to permit withdrawal of the heater from chamber should servicing be required. 6. If two or more heaters are needed to provide the needed heating capacity, arrange them for series gas or vapor flow. EXPLOSION HAZARD. When heating in closed vessels, controls and back-up controls must be used to regulate build-up of temperature and/or pressure. 7. A pressure r