Laars Mini-Therm II JVT (Sizes 50-225) - Install and Ope User Manual Page 1

MINI-THERMLAARSH0071400YFOR YOUR SAFETY: This product must be installed and serviced by a professional service technician,qualified in hot water boile

LAARS Heating SystemsPage 10SECTION 4.Gas Connections4.1 Gas Supply and PipingReview the following general instructions beforecontinuing the installat

Mini-Therm II Hydronic BoilerPage 11NOTE: The boiler and all other gas appliancessharing the boiler gas supply line must be firing atmaximum capacity

LAARS Heating SystemsPage 12A full sized, 1¼" bypass with balancing valves isstrongly recommended for all systems, and requiredwhen: 1) the boile

Mini-Therm II Hydronic BoilerPage 13Figure 6. Typical Plumbing Installations.JVFromSystemToSystemNON-LOW TEMPERATURE SYSTEMS(120°F+ Return Temps)Simpl

LAARS Heating SystemsPage 14Figure 6A. Typical Plumbing Installations.KEY:PUMP CHECK VALVE VALVE ZONE VALVE UNIONAUTO AIR BLEEDERAir Scoop JVBoilerByp

Mini-Therm II Hydronic BoilerPage 155.3 Flow RequirementsAll high recovery, low volume water boilersmust have adequate flow for efficient operation. P

LAARS Heating SystemsPage 165.4 Chilled Water SystemsIf the boiler is installed in conjunction withrefrigeration systems, it shall be installed so tha

Mini-Therm II Hydronic BoilerPage 17123456BK-BLACKW-WHITER-REDY-YELLOWBL-BLUEBR-BROWNO-ORANGEP-PURPLESPARK IGNITION WIRE115V-FACTORY WIRED115V-FIELD W

LAARS Heating SystemsPage 18Figure 9c. Wiring Diagram, Standing Pilot System (JVT).Figure 9d. Schematic, Standing Pilot System (JVT).

Mini-Therm II Hydronic BoilerPage 19SPARKMVMV/PVPVGND24V (GR)24VTH-WMVSPARK123456789W WB BR RLO HIMVCPVHIPilot Burner WithSpark ElectrodeSensorRemote

LAARS Heating SystemsPage 2TABLE OF CONTENTSSECTION 1.General Information1.1 Introduction... 31.2 Warr

LAARS Heating SystemsPage 20Figure 10. Multiple Zone Wiring.For primary/secondary pumping: Connectto "W" in lieu of "A." Boiler re

Mini-Therm II Hydronic BoilerPage 216.3 GroundingWARNINGThe boiler must be electrically grounded inaccordance with the requirements of the authorityha

LAARS Heating SystemsPage 22On continuous pilot ignition models (JVT), if thewater temperature is below the limit setting, theignition module opens th

Mini-Therm II Hydronic BoilerPage 23CautionShould overheating occur or the gas supply fail toshut off, do not turn off or disconnect the electricalsup

LAARS Heating SystemsPage 2415. Replace control box cover.16. Restore power to the boiler and adjust thethermostat high enough to call for heat to ver

Mini-Therm II Hydronic BoilerPage 25DANGERRead and understand this entire procedureprior to proceeding. Improper adjustment ofhigh altitude shutters m

LAARS Heating SystemsPage 261. Lubricate the water circulating pump per theinstructions on the pump.2. If a strainer is employed in a pressure reducin

Mini-Therm II Hydronic BoilerPage 27CautionTwo-stage Operating Control (JV100-225 ONLY):Factory setting is 140°F (60°C). This setting iscorrect for mo

LAARS Heating SystemsPage 28Table 8. Troubleshooting Guide.# Symptom Cause Remedy1. Pump not A. No power A. Check circuit breakers and power source.op

Mini-Therm II Hydronic BoilerPage 299.3 Troubleshooting Honeywell S8600 Intermittent Pilot SystemSome boilers may be equipped with an ignition module

Mini-Therm II Hydronic BoilerPage 3SECTION 1.General Information1.1 IntroductionThis manual provides information necessary forthe installation, operat

LAARS Heating SystemsPage 309.4 Electrical Troubleshooting1. Remove the control box cover on the front of theboiler.2. Verify that 115V is reaching th

Mini-Therm II Hydronic BoilerPage 31Heat Distribution UnitsTransfers heat from the water supplied by the boiler tothe area to be heated through the us

LAARS Heating SystemsPage 32Description Model, Size JVS-50 JVT-50 JVS-75 JVT-75 JVS-100 JVT-100 JVS-125 JVT-125 JVS-160 JVT-160 JVS-225 JVT-225Pilot G

Mini-Therm II Hydronic BoilerPage 33Description Model, Size JVS-50 JVT-50 JVS-75 JVT-75 JVS-100 JVT-100 JVS-125 JVT-125 JVS-160 JVT-160 JVS-225 JVT-22

LAARS Heating SystemsPage 34Figure 15. Parts Identification.11.3Exploded ViewVent DamperDraft DiverterTopRear PanelBurner with Pilot BracketPilot Asse

Mini-Therm II Hydronic BoilerPage 35

H0071400YA subsidiary of BRADFORD WHITE Corporation800.900.9276 • Fax 800.559.1583 (Customer Service, Service Advisors)20 Industrial Way, Rochester, N

LAARS Heating SystemsPage 41. Plumbing materials for the bypass piping, whichis required for:a. Any system where the return watertemperature may be le

Mini-Therm II Hydronic BoilerPage 52.2 Field Assembly1. Mini-Therm II boilers have built-in draft diverterfor natural draft operation.2. Find the vent

LAARS Heating SystemsPage 6CautionDo not force motor operation when operator isfastened to the damper by moving the damperblade, turning the shaft or

Mini-Therm II Hydronic BoilerPage 7SECTION 3.Venting3.1 Combustion Air SupplyThe boiler location must provide sufficientair supply for proper combusti

LAARS Heating SystemsPage 8WARNINGVent pipe diameter must be as required by theNational fuel Gas Code Z223.1 or the CanadianInstallation Codes for Gas

Mini-Therm II Hydronic BoilerPage 9WARNINGOperation of appliances with a blocked commonvent may lead to serious injury or death. Safetydevices must be