Laars Mini-Therm JVi JVH Installation And Operation Instructions Manual

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Laars Mini-Therm JVi JVH Installation And Operation Instructions Manual Manual pdf 10 page image

LAARS HEATING SYSTEMSPage 10speed. Do not operate a summer exhaust fan.Close fireplace dampers.4. Place in operation the appliance being inspected.Follow the lighting instructions. Adjustthermostat so appliance will operatecontinuously.5. Test for spillage at the burner opening after fiveminutes of main burner operation.6. After it has been determined that each applianceremaining connected to the common ventingsystem properly vents when tested as outlinedabove, return doors, windows, exhaust fans,fireplace dampers and any other gas burningappliance to their previous conditions of use.7. Any improper operation of the common ventingsystem should be corrected so the installationconforms with the National Fuel Gas Code,ANSI Z223.1. When re-sizing any portion of thecommon venting system, the common ventingsystem should be re-sized to approach theminimum size as determined using theappropriate tables in Appendix G in the NationalFuel Gas Code, ANSI Z223.1.1I. Water Piping of Boiler SystemFigure 9 shows ‘typical’ plumbing installations.It is recommended that unions and valves are used atthe boiler inlet and outlet so it can be isolated forservice. Check local codes for specific plumbingrequirements before beginning the installation.An ASME pressure relief valve is supplied on allJV boilers, and is pre-set at 30 PSI (207 kPa). Therelief valve outlet piping must discharge to a drain.Under no circumstances should the relief valve pipingbe a closed circuit.A pressure reducing valve (automatic feed) mustbe used to maintain system at constant proper pressure(see Figure 9). Supply properly installed purge valvesto eliminate air from each circuit.A drain valve is supplied with the boiler, and canbe found in the plastic bag shipped with each boiler.This valve is to be installed on the lower right side ofthe boiler (see Figure 2) and is used for draining theunit. To drain the boiler completely, open the drainvalve and remove the two drain plugs located on thelower left side of the boiler.Be sure to include air vent devices located at thehighest point in the system to eliminate trapped air,and an air elimination device near the outlet side ofthe JV boiler. Manual vent valves are recommended.Hot water piping should be supported by suitablehangers or floor stands, NOT by the boiler. Due toexpansion and contraction of copper pipe,consideration should be given to the type of hangersused. Rigid hangers could transmit noise through thesystem caused by the piping sliding in the hangers. Itis recommended that padding be used when rigidhangers are installed.A properly sized expansion tank must beincluded in the system. Laars offers an air-chargeddiaphragm-type expansion tank, with an automaticfeed valve, which includes a pressure regulator set at12 psig.1I-1. By-Pass PipingThe following information and suggestions aremade on by-pass piping as it affects the temperaturerise at the boiler. A boiler temperature rise must betaken on all JVi boiler installations. If the temperaturerise exceeds 30°F (17ºC), it is an indication that theboiler is not receiving adequate water flow. Check thepump for any obstruction, replace the pump with alarger size where necessary, or install a system by-pass (illustrated in Figure 9).On JVi sizes 125, 160, and 225 with a multiplezone system, a by-pass is required to ensure properflow in addition to properly sized circulator and pipingsystem.NOTE: On JVi sizes 160 and 225 a primary/secondary piping system is recommended. In thissystem, a circulator is dedicated to pumping the boileronly. This circulator should be sized for the boilerhead loss and flow rate.The two above piping configurations can alsoapply to JVi sizes 50, 75 and 100, but generally, theseunits require flow rates which are easily obtainedwithout a by-pass.All precautions must be taken by the installer toinsure that a maximum temperature rise through theboiler does not exceed 30°F (17ºC). The temperaturerise on boilers installed in multi-zone systems usingzone valves must be taken when the zone of thelongest length and/or the zone of the highest head lossis open.Please note that a 1" (25mm) diameter by-passwith balancing ball valve must be installed if a returnwater temperature of below 110°F (43ºC) is expectedunder operating conditions (see Figure 9).1J. Chilled Water SystemsIf the boiler is installed in conjunction withrefrigeration systems, it shall be installed so that thechilled medium is piped in parallel with the heatingboiler with appropriate valves to prevent the chilledmedium from entering the heating boiler.When boiler piping is connected to heating coils,which are in close proximity to refrigerated aircirculation, there must be flow control valves or otherautomatic methods to prevent gravity circulation ofthe boiler water during the cooling cycle.