Raypak MVB 504A Installation & Operating Manual

Raypak MVB 504A Installation & Operating Manual Manual pdf 35 page image

35The vent cap is not considered in the overall length ofthe venting system.Care must be taken during assembly that all joints aresealed properly.The vent must be installed to prevent the potential ac-cumulation of condensate in the vent pipes. It isrequired that:1. The vent must be installed with a slight upwardslope of not more than 1/4 inch per foot of hori-zontal run to the vent terminal.2. The entire vent must be double wall or insulatedthrough its length.TerminationThe vent cap MUST be mounted on the exterior of thebuilding. The vent cap cannot be installed in a well orbelow grade. The vent cap must be installed at least 1ft above ground level and above normal snow levels.The vent cap MUST NOT be installed with any com-bustion air inlet directly above a vent cap. This verticalspacing would allow the flue products from the ventcap to be pulled into the combustion air intake installedabove.This type of installation can cause non-warrantableproblems with components and poor operation of theheater due to the recirculation of flue products. Multi-ple vent caps installed in the same horizontal planemust have a 4 ft clearance from the side of one ventcap to the side of the adjacent vent cap(s).Combustion air supplied from outdoors must be free ofparticulate and chemical contaminants. To avoid ablocked flue condition, keep the vent cap clear ofsnow, ice, leaves, debris, etc.Outdoor InstallationUnits installed outdoors must be vented with listedCategory I (Type B double-wall or equivalent) ventmaterial per the following instructions and installedwith the factory-supplied outdoor vent kit. A specialvent cap and air intake elbow are provided in accor-dance with CSA requirements. These must beinstalled directly on the vent pipe as illustrated inFig. 36.Care must be taken when locating the heater out-doors, because the flue gases discharged from thevent cap can condense as they leave the cap.Improper location can result in damage to adjacentstructures or building finish. For maximum efficiencyand safety, the following precautions must beobserved:1. Outdoor models must be installed outdoors andmust use the outdoor vent cap and air intakeelbow available from the manufacturer (salesorder option D-11).2. Periodically check venting system. The heater’sventing areas must never be obstructed in anyway and minimum clearances must be observedto prevent restriction of combustion and ventilationair. Keep area clear and free of combustible andflammable materials.3. Do not locate adjacent to any window, door, walk-way, or gravity air intake. The vent must belocated a minimum of 4 ft horizontally from suchareas.4. Install above grade level and above normal snowlevels.5. Vent terminal must be at least 3 ft above anyforced air inlet located within 10 ft.Freeze ProtectionTo enable freeze protection, dip switch position 7 (onthe PIM™) must be turned on (UP position). This isthe default position.If the water temperature drops below 45˚F on theOutlet or Inlet sensors, the Boiler pump is enabled.The pump is turned off when both the Inlet and Outlettemperatures rise above 50˚F.WARNING: No substitutions of flue pipe or ventcap material are allowed. Such substitutions wouldjeopardize the safety and health of inhabitants.NOTE: The vent cap and air intake elbow must befurnished by the heater manufacturer in accordancewith its listing (sales order option D-11).CAUTION: A listed vent cap terminal adequatelysized, must be used to evacuate the flue productsfrom the building.