Bradford White RTG 199 MEN, Инструкция по установке и эксплуатации

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Installation instructions
RTG 199 ME – 6 720 811 615 (2015/04) 20
If an external condensate drain (installer supplied) must be installed
(chapter 4.3.2), the following is recommended:
• 1. Install condensate drain on a horizontal section of the exhaust pipe
as close to the heater as possible.
• 2. The condensate must be disposed of according to local codes.
• 3. To install condensate drain in vent system, use stainless steel
condensate drain tee. Refer to table 21 for approved condensate
drain parts numbers.
Fig. 22 External condensate drain installation (combustion air piping
not shown)
[1] Appliance
[2] Condensate drain trap
[3] Elbow
[4] Firestop support
[5] Rain cap
[6] Storm collar
[7] Flashing
[8] 4" minimum air space
[9] Condensate drain Tee
4.3.6 Freeze prevention
In cold climates, components of a tankless water heater can freeze and
burst from negative draft. A leading cause of negative draft is
combustion appliances in the building not being supplied with sufficient
combustion air. A wood stove or furnace can pull its combustion air from
the water heater‘s vent pipe, allowing the cold incoming air to freeze the
cold water in the heat exchanger. Supplying more combustion air for all
combustion appliances is the solution. A HVAC specialist should be
consulted to design solutions for providing more combustion air.
Listed below is an additional measure designed to further limit backdraft
in extreme conditions assuming all other possible causes have been
addressed.
Solution One
The Z-flex vent termination hood is the preferred option for limiting
backdraft under the following conditions (see fig. 23):
• The vent hood is only to be used in the exhaust vent piping.
• The vent hood can only be used for horizontal terminations.
• The vent hood is able to meet the required clearances outlined in the
venting section of the water heater‘s installation manual.
Fig. 23 Part nr. 2SVSHTD03 for 3" venting
Part nr. 2SVSHTD04 for 4" venting
Solution Two
If the required clearances of the Zflex termination hood cannot be met,
the Zflex damper is the preferred alternative (see fig. 24).
Fig. 24 Part nr. 2ZVBP03 for 3" venting
Part nr. 2ZVBP04 for 4" venting
Installation
For this solution to be effective, the internal flapper must be 100%
closed when the water heater is not running. Refer to Figures 25 and 26
for preferred installation positions in the vent system.
If using the Zflex damper:
• Ensure directional arrow on damper label faces in the same direction
as exhaust flow.
• If installed horizontally, the axis must be horizontal or slightly pitched
up towards termination to ensure damper closes 100% when heater
is not running.
• To allow accessibility, damper must not be installed in an enclosed
section of vent pipe.
Use materials approved by the authority having
jurisdiction. In the absence of other authority, PVC, and
CPVC pipe must comply with ASTM D1785, F441
orD2665. Cement and primer must comply with ASTM
D2564 or F493. For Canada, use CSA or ULC certified
PVC or CPVC pipe, fittings and cement, see table 5.
3" Venting Z-flex ProTech Heat Fab
90°
Condensate
Drain Tee 2SVEVWCF03 FST3 & FSDF3 93PPLSTEE
Horizontal
Condensate
Drain 2SVEDWCF03 FSHDT3 9321
Condensate
Drain Tube 2SVEDTK24 N/A 7000TUBE
Table 21 Approved Condensate Drain Part Numbers
6720608542-07.1V
6720608542-08.1V