A.O. Smith VB 1500 User Manual Download Page 21

21

Any safety devices including low water cutoffs used in conjunction 

with this boiler should receive periodic (every six months) inspection 

to assure proper operation.  A low water cutoff device of the float 

type should be flushed every six months.  Periodic checks, at least 

twice a year, should be made for water leaks.

More frequent inspections may be necessary depending on water 

conditions.

The boiler-mounted gas and electrical controls have been designed 

to give both dependable service and long life.  However, malfunction 

can  occur,  as  with  any  piece  of  equipment.    It  is  therefore 

recommended that all components be checked periodically by a 

qualified serviceman for proper operation.

RELIEF VALVE

The safety relief valve should be opened at least twice a year 

to check its working condition.  This will aid in assuring proper 

pressure relief protection.  Lift the lever at the top of the valve 

several times until the valve seats properly and operates freely.

BLOWER COMPARTMENT

The blower compartment should be cleaned annually to remove 

any dirt and lint that may have accumulated in the compartment or 

on the blower and motor.  Buildups of dirt and lint on the blower 

and motor can create excessive loads on the motor resulting 

in  higher  that  normal  operating  temperatures  and  possible 

shortened service life.

BURNER MAINTENANCE

Qualified servicers should follow this procedure when the boiler’s 

burner needs cleaning.

1.  Turn off the electrical power to the boiler and close the main 

manual gas shutoff valve(s). Allow the boiler parts to cool before 

disassembly.

2.  Loosen the flange and separate the gas train from the manifold 

assembly.

3.  Separate the burner from the blower adapter by first removing 

the four (4) bolts and subsequently, the blower gas kets. The 

blower should be free to move at this point.

  FOR DIRECT VENT UNITS: It is necessary to loosen and 

slide the rubber coupling on the blower adaptor in order to 

move the blower.

4.  Loosen the seven bolts on the blower adapter at the base and 

move the burner ground wire (Green) aside.

5.  Lift the blower adapter and remove the manifold assembly up 

from the 6 studs located on the cover plate and remove the 

burner gasket.  

6.  Remove any loose foreign material such as dust or lint with a 

vacuum. Check all ports for blockage.  Dislodge any foreign 

material causing blockage. Remove any soot or carbon deposits 

with a rag making sure to remove any lint  left on the burner by 

vacuuming again.

7.  Reverse the steps to reassemble the unit.

8.  Restore electrical power and gas supply to the boiler.

  •  Put the boiler back in operation by following the Lighting and 

Operating instructions in this manual.

  •  Check for gas leaks and proper boiler and vent operation.

CONDENSATE REMOVAL SYSTEM

Due to the highly efficient operation of this unit, condensate is 

formed during operation and must be removed by the conden-

sate drain systems. Inspect the condensate drains and tubes 

at least once a month and insure they will allow the free flow of 

condensate at all times. The system must be inspected more 

frequently in cold weather if the drain system is located in an 

area, such as along the floor, where freezing tempera tures are 

likely to occur. The conden sate drain system must be protected 

against freezing. Contact a qualified service agent to inspect 

and correct the condition if freezing of the conden sate lines 

is a problem.

The transparent drain lines and condensate drain on the bottom 

of the vent collector should be visually inspected at one month 

intervals for blockage, particularly in the areas of the loops in the 

lines which trap a small amount of conden sate, and the exit point 

of the vent collector drain.  Conden sate in portions of the line other 

than the loop area indicates a blockage in the drain line.  Flush the 

Summary of Contents for VB 1500

Page 1: ...one in your building Immediately call your gas supplier from a neighbor s phone Follow the gas supplier s instructions If you cannot reach your gas supplier call the fire department Installation and s...

Page 2: ...ning Procedure Mechanical Removal of Deposits 22 Replacement Parts 22 LIMITED WARRANTY 23 TABLE OF CONTENTS 2 safe installation use and service 3 APPROVALS 3 GENERAL SAFETY 4 INTRODUCTION 5 INSTALLATI...

Page 3: ...hazardous situation which if not avoided could result in property damage WARNING CAUTION CAUTION DANGER All safety messages will generally tell you about the type of hazard what can happen if you do...

Page 4: ...etup and instructions before lighting Failure to implement the proper setup will result in improper and inefficient operation of the appliance resulting in production of increased levels of carbon mon...

Page 5: ...ion The installation must conform to all instructions contained in this manual and the local code authority having jurisdiction These should be carefully followed in all cases Authorities having juris...

Page 6: ...e horizontally vented gas fueled heating appliance or equipment The sign should read in print size no less than one half 1 2 inch in size GAS VENT DIRECTLY BELOW KEEP CLEAR OF ALL OBSTRUCTIONS INSPECT...

Page 7: ...DB F3 7 5 AMP FUSE MCB II F1 24VDC GENERATION MCB II K6 RELAY COIL MCB II MR HIGH LIMIT FLOW SWITCH LWCO SWITCH OPTIONAL LOW GAS SWITCH HIGH GAS SWITCH OPTIONAL EXTERNAL ENABLE OPTIONAL POWER ACC PROV...

Page 8: ...LE EXT ENABLE DISABLE COM NO COM NC NO COM COM NC ON OFF POWER RELAY NO COM G W W BK BK BK BK BK W 24VAC HOT W BK 24VAC RTN G GROUND F CAT 5 CABLE R G BK W MCB II DETAIL A Part of J BOX VB VW 1500 200...

Page 9: ...W UNITS COME EQUIPPED WITH PUMP VB UNITS DO NOT 24VAC COM PUMP RELAY A BK F 0 WIRING DIAGRAM TRANSFORMER 120 24 VAC MODULATING CONTROL BOARD II MCB II J20 or J21 J16 1 2 6 7 J24 F1 7 5A 24VAC J3 1 2 3...

Page 10: ...and permit pressure to be established by the pressure reducing valve 2 Vent all high points in system to purge system of air Provisions should be made to permit manual venting of radiators or convecto...

Page 11: ...water temperature or 20 F 11 C differential whichever has the higher inlet temperature is attained b If the inlet water temperature is greater than 120 F 49 C and the 20 F 11 C differential is not pre...

Page 12: ...12 LIGHTING AND OPERATING INSTRUCTIONS...

Page 13: ...efully adjust the low fire gas setting to achieve the CO2 level prescribed in above reference table Note The rotation of the Low Fire adjustment is opposite of the High Fire as follows Clockwise rotat...

Page 14: ...t will operate with the voltage and current level provided Pump MCB 120VAC required on systems that do not have an external pump Provides electrical power to directly operate a pump or the coil of an...

Page 15: ...idle state as displayed by the Standby LED The control will continue to monitor heat demand and state of other system devices Upon a drop of water temperature below the set parameters the control wil...

Page 16: ...when the fault state is exited Hard Fault State See Fault Description section for list of soft and Auto Reset faults The pump remains on for the selected post circulate time to cycle the hot water ou...

Page 17: ...soft lockout condition will occur and burner will be shut off This fault condition is automatically cleared when temperature drops below high limit setpoint minus high limit differential AUTO HIGH LI...

Page 18: ...nwards in screens to reach a desired item and to change setpoints and user settings They have an auto increment decrement feature for some of the configurations and values When you first press one of...

Page 19: ...the MCB and reading the resistance across the two active pinsontheconnectoratthe end of the probe cable The value should be approximately 0 ohms when the temperature of the probe is less than 220 F L...

Page 20: ...unction of the servo pressure regulator Replace the valve and add a gas filter in front of the new valve preventative maintenance This is a pre mix burner system The flame is not supposed to be direct...

Page 21: ...to move at this point FOR DIRECT VENT UNITS It is necessary to loosen and slide the rubber coupling on the blower adaptor in order to move the blower 4 Loosen the seven bolts on the blower adapter at...

Page 22: ...xist As the water is heated these tend to drop out depositing as scale or lime This scale must be removed before the heat exchanger tubes become blocked DELIMING The amount of calcium carbonate lime r...

Page 23: ...his boiler under state or provincial law are limited to one 1 year duration for the boiler or any of its parts Some states and provinces do not allow limitations on how long an implied warranty lasts...

Page 24: ...24 500 Tennessee Waltz Parkway Ashland City TN 37015 Technical Support 800 527 1953 Parts 800 433 2545 Fax 800 644 9306 www hotwater com...

Reviews: