Monessen Hearth HBDV300 User Manual

26 

Flex vent pipe spacers: Refer to manufacturer’s 
specifi cations for correct positioning of the spacer springs to 
maintain proper distance between inside and outside pipe.

NO

TE

UL1777

Flex vent

Securing screws 

(3 places 

equidistant just 

above gear 

clamp) 

Gear clamps

DVFA/8 

inner adapter
outer adapter

Appliance starting 

collar

1¾ in. fl exible pipe 

and adapter outer 

collar overlap

UL1777

Flex vent

5" radius

Figure 1 —

Typical appliance connection

Figure 2 —

Minimum radius for fl ex vent section

1.  Flexible UL1777 listed venting may be used in any venting 

application where rigid direct vent components can be used. 
All restrictions, clearances and allowances that pertain to 
the rigid piping apply to the fl exible venting. Flex kits may 
not be modifi ed. Flex kits may be added to the end of a vent 
run made of rigid vent sections using pipe manufacturer’s 
approved fl ex to pipe adapters. This may occur only if doing 
so does not violate any of the venting length, height, 
routing, horizontal to vertical ratio requirements or 
clearance considerations detailed in this manual.

2.   The fl ex adapter starter kit (DVFA/8) is used to attach fl ex 

venting to the appliance starting collar. It includes 4" inner 
and 7" outer adapter rings (refer to Figure 1). 

 •  The inner and outer adaptor rings are required to start  

 

all fl ex runs.

 •  Never install damaged or torn fl exible venting.
 •  Over tightening clamps may rip, tear, or otherwise  

 

damage fl exible venting.

 •  The adaptor kit does not include individual pipe    

 

sections which may be purchased separately. (UL1777    

 

listed type fl ex venting only.)

 

A.  Installing the inner fl ex adaptor and pipe (see Figure 1).

 

 

1.  Insert the long side of the 4" inner ring inte exhaust

 

 

pipe, gently tap to seat into place, and secure with  

  screws.

 

 

2.  Slide the small gear clamp over the inner fl exible vent pipe, and push out of the way.

 

 

3.  Pull and extend the inner fl exible vent.

 

 

4.  Slide the inner vent onto the adapter collar, for a minimum 1¾" overlap.  

 

 

5.  Locate the clamp at approximately ¾" from the fl ex end and tighten.

 

 

6.  Secure the clamped inner section with three self tapping screws, drilled equidistance, just above the clamp  

 

  perimeter.

 

B.  Installing the outer fl ex pipe (refer to Figure 1). 

 

 

1.  Firmly insert the outer adapter ring into the outer appliance starting collar and secure with screws.

 

 

2.  Slide the large gear clamp over the outer fl exible vent pipe, and push out of the way.

 

 

3.  Pull and extend the outer fl exible vent.

 

 

4.  Slide the outer vent onto the appliance collar outer adapter for a minimum 1¾" overlap.

 

 

5.  Locate the clamp at approximately ¾" from the fl ex end and tighten.

 

 

6.  Secure the clamped outer section with three self tapping screws, drilled  

 

 

equidistant, just above the clamp perimeter.

 C. 

Routing 

UL1777 

fl ex pipe.

 

 

1.  Always maintain the required clearance when routing the fl ex vent assembly. 

  2. 

Install 

fi restop spacers (see Figure 3) when penetrating ceilings, 

 

 

attic spaces, or walls.