Navien NHB-055 Service Manual page 52

Item
(F) Space Heating
Max Heat Capacity
(G) Pump Freeze
Protection
Temperature
Setting
(H) Anti Fast
Cycling Time
(I) CH Pump Over-
run Time
(J) Domestic Hot
water(DHW) Max
Heat Capacity
52 NHB Service Manual
This menu is used to configure the desired space heating capacity. When the
boiler operates in the Normal mode, the space heating capacity is limited to
the set value (%)
Setting range
( [heating min. heat capacity + 20%] ~ 100% )
This menu is used to configure the circulation pump freeze protection
temperature.
When the space heating supply temperature stays below the set value for
longer than 10 seconds, the boiler runs the circulation pump to prevent freeze
damage (the pump runs for 10 minutes, then stops for 1 minute).
Setting range
43 ~ 50°F(6 ~ 10°C)
The anti-fast cycling time is the duration that the boiler stops its space
heating operation when the space heating supply or return temperatures
reach the set values for boiler operation stop temperatures. The boiler will
not resume space heating until the duration elapses, even when the space
heating supply or return temperatures return to within the set ranges.
Setting range
0-20 minutes
The pump overrun time is the duration that the circulation pump will
continue to run when the space heating supply or return temperatures reach
the set values for boiler operation stop temperatures and the burner turns off.
If the space heating supply or return temperature remains out of the boiler
operation temperature range after the set time, the boiler stops the pump for
10 minutes, runs it again for 5 minutes, and then repeats the cycle.
Setting range
3-40 minutes
This menu is used configure the desired DHW capacity. When the boiler
operates in the Normal mode, the DHW capacity is limited to the set value (%)
Setting range
([DHW min heat capacity + 20%] ~ 100%)
Description
Default
50°F(10°C)
Default
3 minutes
Default
40 minutes
MAX heat capacity for
Space heating is 95%
Default
100%
For Celsius (°C) mode;
ex) at 10°C
For Fahrenheit (°F) mode;
ex) at 50°F
If Anti Fast Cycling Time set is
3 minutes
If CH PUMP Over-run Time set is
40 minutes
If Max limited hot water calories
is 100%
Default
100%
Display
Version 1.0