A.O. Smith 100 Series Start-up Instructions

Start-up Instructions

VB/VW 500/750/1000

Series 100/101

Before starting the boiler, please review the boilers instruction manual (AOS Part Number 212800) supplied with the boiler. This 

is a powered combustion copper tube boiler. Please contact an authorized A.O. Smith representative before starting the unit. 

Ensure that the water piping, gas line, controls, and venting have been installed per the instruction manual.

Gas supply lines should be sized in accordance with the current edition of National Fuel Gas Code (ANSI Z223.1/NFPA 54) or 

CAN/CSA B149.1 The Canadian Natural Gas and Propane Installation Code.

Make sure the boiler is not damaged. If the unit is damaged, contact an A.O. Smith representative for service or replacement 

parts prior to starting the boiler. 

This boiler is equipped with a Modulating EMC 5000 control system. The EMC 5000 displays the system status and errors that may 

occur during normal operation. For full details on the controls, please refer to the Installation Manual supplied with the boiler. The 

boiler must be installed according to the instructions provided with the unit. Failure to do so will void the warranty. 

The following test equipment should be on hand: (all test equipment must be acclimated to ambient temperature before calibration 

and use.) 

• AcombustionanalyzercapableofmeasuringCOandCO

2

 or O

2

.

• Adigitalmanometerorpressuregaugescapableofaccuratelydisplaying0–15(±.01)inchesofwatercolumn.

• Combinationvolt/ammeter

• TORX®T40or5mmhexwrench–forsettinggasmixtureatgasvalve

• 3mmor7/64inhexwrench–forsettinggasmixtureatgasvalve

I. Verify utilities

• Ensurethatthewaterpiping,gasline,controls,andventinghavebeeninstalledpertheinstructionmanual.

• Becertainthatthesystemisfullofwater,thatairispurgedfromalllines,theboiler,andstoragetank.

• Ensurethatnoleaksarepresentandthatallsupplyandreturnwatervalvesareopen.

• Upstreamgasvalveshouldremaincloseduntilstartup.

II. Component Sequence Verification

• Ensurethatthepowersupplymeetstheserequirements:singlephase,Minimum:108VACRMS;Maximum:132VACRMS

and is on a dedicated circuit breaker with separate neutrals and grounds. 

• Ensureallcontrolwiringisruninadedicatedconduitperinstructionmanual.

• Performpowersupplytestoutlinedintheinstructionmanual.

• Ensurethattheupstreammanualgasvalveoftheboilerisopen.

Priortoturningonthegas,propersequenceofmostofthesystemcanbeverified.Withthewaterturnedon,andthegasturned

off by the downstream manual valve, start the system and allow it to run through a heating cycle. It should stop when it checks for 

theflameanddeclareafault.Thiswillverifythatthepump,flowswitch,igniter,variablefrequencydrive,modulatinggasvalve,

blower and low/ high blower prover switches are all functioning properly.

III. Initial Boiler Set-up Verification

• Drillamaximum7/16”holeinthesideoftheventbootteeapproximately8”frombackpaneltoinsertthegasanalyzerprobe. 

  The hole must be sealed upon completion of the start-up testing.

• Openthedownstreammanualgasvalvetotheboilerandpurgeairfromtheline.

PRINTED0608

212936-002