Eternal GU145 Series, Installation And Operation Manual

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Common Vent Installation
Systems
In MCU with common vent systems, GU195M models are used and being a condensing water heater, combustion
gases are discharged at a very low temperature. It is therefore necessary for the vent system to be perfectly
impermeable to combustion condensate and to be made of corrosion resistant materials. The various funnel joints
must be well sealed in order to avoid any condensate drain and leakage of flue gas.
The power vent system is for a multi control of units installed in a sufficient vented room with sufficient supply of
combustion air. Air intake comes from a well ventilated, heated room with clean air supply. Use an air filter if necessary.
Power Vent
For direct vent system we can use the same materials for the air intake system as used for the power vent system.
The connection for the flue gas and air intake system can be positioned on the right as well as on the left side of
multi control units.
Direct Vent(Sealed Vent)
Multi Units With Common Vent
POWER VENTED
Dimensions Of Installation
DIRECT VENTED
The maximum length is the sum of the equivalent straight of horizontal runs, vertical runs and elbows of common vent pipe.
One 90
º elbow is equivalent of 5 feet.
Example: when installing 2 units on 4 ” common vent, the maximum vent length is 50 ’ and if 3 elbows are used
then the run cannot be more than 35 ’ .
Horizontal runs shall be slopping upwards not less than 1/4 inch per foot to the vent termination.
Number of units Common vent size (inches) Maximum length of vent (L) Allowed number of 90 º elbow
2 4 inches 50 ft 3
3 5 inches 55 ft 4
4 6 inches 60 ft 5
Number of units Common vent size (inches) Maximum length of vent and
air intake (ft) Allowed number of 90 º elbow
2 4 inches 20 ft 3
3 5 inches 25 ft 3
4 6 inches 30 ft 4
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Applicable Model
GU195 (M) / 508 (11,12,21,22)1195 (M)