Справочник Пользователя для State Industries SUF-60-120

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if  firing  rate  adjustment  is  required  follow  these  instructions  to 

determine the actual firing rate of the water heater:
1.  Ensure there are no other gas fired appliances connected to 

the gas meter firing during this test.

2.  Contact the gas supplier to determine the heating value, in 

Btu per cubic foot, of the gas supply.

3.  Connect  a  manometer  to  the  manifold  gas  pressure  tap. 

4.  Start the water heater and ensure it is firing.
5.  Check the manifold gas pressure, refer to Table 4 on page 14 

for correct pressure. See manifold Gas Pressure Adjustment 

on page 54 if adjustment is necessary.

6.  Locate the gas meter serving the water heater.
7.  Time how long (in seconds) it takes for one cubic foot of gas 

to be used while the water heater is firing with a stop watch.

8.  Use the formula below to “clock” the gas meter and determine 

the actual firing rate of the water heater based on the heating 

value (Btu per cubic foot) of the gas supply:

x  H  =  Btu/hr

3600

T

x  1050  =  300,000 Btu/hr (87.9 kW)

3600

12.6

Example:

•  3600 = seconds in one hour.
•  T = time, in seconds, to burn one cubic foot of gas.
•  H = heating value of gas in Btu per cubic foot. 
•  Btu/hr = actual firing rate of the water heater.

note: 1050 Btu per cubic foot is a standard value for 

natural gas. Standard propane gas Btu content is 2500 

Btu per cubic foot. Btu values may change in certain 

areas and at high elevations. Check with the local gas 

utility company.

to turn off gas
1.  Change the Operating Set Point to the lowest temperature 

setting, see Operating Set Point And Differential Adjustment 

2.  When the water heater has completed its shut down sequence 

and enters the standby mode, turn the water heater’s on/off 

switch to the “off” position.

3.  Close the main Gas Shutoff Valve, see Figure 52 on page 39.

Gas and carbon monoxide detectors are

available.

Overfiring could result in fire or

explosion.

Under no circumstances should the 

input exceed the rate shown on the 

water heater’s rating label. 

              

Breathing carbon  monoxide can cause brain  damage or

death.  Always read and understand  instruction  manual.

Under no circumstances should

the input exceed the rate shown

on the water heater’s rating label. 

Overfiring could result in damage to

the water heater and sooting.

Gas and carbon monoxide detectors

are available.

SUF  100  120  and  SUF  100  150  models  are  certified  for  use 

without modification for altitudes up to 7,700 feet (2,347 m).
SUF  100  199  and  SUF  100  250  models  are  certified  for  use 

without modification for altitudes up to 10,100 feet (3,078 m).
most gas utility companies de-rate their gas for high altitudes, 

making it unnecessary to install high altitude orifices. 
For installations above the certified elevations listed above call 

the technical support phone number listed on the back cover of 

this manual for further technical assistance. Call the local gas or 

utility company to verify Btu per cubic foot content before calling 

for technical assistance and have that information available.
note: The actual firing rate of the water heater must not exceed 

the  input  rating  on  the  water  heater's  rating  label  under  any 

circumstances.
note:  Due  to  the  input  rating  reduction  at  high  altitudes,  the 

output  rating  of  the  appliance  is  also  reduced  and  should  be 

compensated for in the sizing of the equipment for applications.