Bradford-White Corp 500-1825 Manual De Usuario

Internet Version for Reference Only

Page 16

B4 Volume Water Heater

Page 17

When a tank aquastat is not used:

The pump on the heater must run continuously, 

so the heater's temperature control will sense the tank's 

water temperature. Set the heater temperature control 

to the desired tank temperature. Set the manual reset 

high limit 50°F higher than the heater temperature 

control. Example: If desired temperature is 140°F, set 

the heater temperature control at 140°F, and set the 

manual reset high limit at 190°F.

1.      Turn off main electric switch.

2.      Close all manual gas valves.

To shut down heater, turn off all manual gas 

valves and electrical disconnect switches. Whenever 

danger of freezing exists, shut off water supply and 

remove drain plug in the bottom of front header 

cover. Drain every part of system subject to freezing 

temperature.

1.      Lubricate the water circulating pump (see 

instructions found on the pump).

2.      If a strainer is employed in a pressure reducing 

valve or in piping, clean it every six (6) months.

3.      At start-up and every six (6) months thereafter, 

the pilot and main burner flame should be 

observed for proper performance (see Figure 18). 

See attached lighting and shut-down instructions 

for proper pilot flame pattern). If flame has the 

appearance of “sooting” tips, check for debris 

near orifices. Call serviceman.

4.      Inspect the venting system for obstruction, 

leakage and corrosion at least once each year.

5.      Keep heater area clear and free from combustible 

material, gasoline and other flammable 

vapors and liquids (see Table 1 for minimum 

clearances).

6.      Be certain all combustion air and ventilation 

openings are unobstructed.

7.      Check for fouling on the external surfaces of 

the heat exchanger every six months. (NOTE: 

After installation and first start-up, check the heat 

exchanger for fouling after the following periods 

of operation: 24 hours, 7 days, 30 days, 90 days, 

and once every six months thereafter).

         Fouling on the external surfaces of the heat  

exchanger is caused by incomplete combustion 

and is a sign of combustion air and/or venting 

problems. As soon as any fouling is observed, 

the cause of the fouling should be corrected (see 

Section 5, Troubleshooting Guide). The heat 

exchanger can be checked by locating a mirror 

under the burners with a flashlight. An alternate 

method is to remove the venting and top panel as 

necessary to inspect from above. Also check the 

vent system for defects at this time.

         a.     If cleaning is required, shut off all electrical  

and gas supply to the heater.

         b.     To expose the heat exchanger:

         Remove flue pipe, top of unit, rear upper jacket, 

flue collector rear panel and heat exchanger 

baffles.

         Remove vent top assembly, rear upper jacket, 

flue collector rear panel and heat exchanger 

baffles.

         c.     Remove all burners:

        It is usually more convenient to remove 

the  burner tray assembly. Disconnect 

sensor wire, ignition cable (or thermocouple 

generator) and pilot gas line. Disconnect 

manifold inlet union(s). Remove the four 

(4) retaining screws. Grasp burner/pilot 

assembly firmly at the front. Push it back, 

disengaging it from the gas orifice. Lower 

the front of the burner (to avoid damaging 

pilot shield) then remove the burner tray.

Pilot Reset

Switch