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LAARS HEATING SYSTEMS

Page 16

6.

On each affected burner, slowly close the air
shutter until a normal flame is observed then re-
tighten its associated locking screw.

7.

Turn the boiler off.

8.

Perform System Start-Up in accordance with
Section 2A of this manual.

9.

Observe flame pattern on all burners. If the flame
on any burner is pulsing, unstable or lifting then
repeat steps 5 and 6 until all burners are
exhibiting a normal flame.

10.

Re-install the burner cover and tighten it in
place.

2A-3. Sequence of Operation

1.

Wall thermostat calls for heat.

2.

The damper activator rotates damper blade to
open position. Indicator light comes on.

3.

Pump relay will turn on the circulating pump.

4.

If water temperature is below the limit setting on
the spark ignition models will light the pilot and
check the flame existence.

5.

After pilot is proven to be lit, the main gas valve
will open, the main burners will ignite and
continue until either the hi-limit or wall
thermostat opens.

6.

When the wall thermostat is satisfied, the burners
will shut off. The pump relay will turn off the
pump, and the damper will close. When the room
temperature falls below the wall thermostat
setting, the cycle will repeat.

Note: When equipped with pump delay option,

the pump will run for short time after the burners turn
off and the damper closes.

2B. Water Temperature Setting

In Canada, for models equipped with modulating

gas valves, in addition to the main gas valve. These
controls are factory set at "5" which is satisfactory for
most installations. Lower settings may be appropriate
for radiant floor systems, or when heating
requirements are low. To change the factory setting
simply adjust the red knob on the valve to the desired
water temperature according to Table 7 (temperatures
are approximate).

2C. Maintenance

1.

Lubricate the water circulating pump per the
instructions on the pump.

2.

If a strainer is employed in a pressure reducing
valve or the piping, clean it every six months.

3.

At start-up, and periodically thereafter, the
burner flame should be observed. If the flame
has the appearance of 'sooting' tips, check for
debris near the orifices and call the service
technician.

4.

Inspect the venting system for obstruction,
leakage or corrosion at least once a year.

5.

Keep the boiler area clear and free from
combustible materials, gasoline, and other
flammable vapors and liquids.

6.

Be sure that all combustion air and ventilation
openings are unobstructed.

7.

Upon completion of the installation, inspect the
external surfaces of the heat exchanger for
fouling based on the following schedule:

24 hours 7 days 30 days 90 days

Once every six months thereafter.

8.

If the boiler is not going to be used for long
periods of time in locations where freezing
occurs, it should be completely drained of all
water. To accomplish this, there is a drain valve
on the right side of the boiler which can be
opened. This will drain the right side of the
boiler. There are two plugs located on the left
side of the heater which must be removed to
drain that side. Both sides must be drained.

9.

The gas and electric controls on the boiler are
engineered for long life and dependable
operation, but the safety of the equipment
depends on their proper functioning. It is
strongly recommended that the basic items listed
below be inspected by a qualified service
technician every year.

a.

Water temperature controls

b.

Pilot safety system.

c.

Automatic gas valves.

d.

Flow sensing safety devices.

e.

Vent dampers and power venters.

Figure 13.

1) JVS Pilot; 2) JVH Pilot;
3) Main Burner Flame Pattern; 4) JVT Pilot.

Table 7. Water Temperature Settings.

Dial

Number

1

2

3

4

5

6

7

8

9

Temp. °F 120

135

150

165

180

195

210

225

240

Temp. °C

49

57

66

74

82

91

99

107

116

Summary of Contents for Mini-Therm II JV

Page 1: ...or explosion may result causing property damage personal injury or loss of life Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance WHAT T...

Page 2: ...1H Venting 7 1H 1 Common Venting System 8 1I Water Piping of Boiler System 8 1I 1 By pass Piping 8 1J Chilled Water Systems 10 1K Electrical Wiring 10 1L Filling the System 12 SECTION 2 Installation...

Page 3: ...installation Consult the Laars factory or local factory representative with any problems or questions regarding this equipment Experience has shown that most operating problems are caused by improper...

Page 4: ...Temperature rise must be measured with the longest highest head zone calling for heat alone Other factors to be considered before selecting a pump are pipe size the number of fittings throughout the s...

Page 5: ...gas piping from the gas meter to the boiler 3 A trap drip leg must be provided ahead of the gas controls see Figure 4 A manual gas shutoff valve must also be provided for service convenience and safe...

Page 6: ...an indication of an undersize gas meter and or obstructed gas supply line 5 The correct burner manifold gas pressure is stamped on the rating plate The regulator is pre set at the factory and normally...

Page 7: ...de with rustproof sheet metal screws IMPORTANT NOTE Do not use sheet metal screws at the snap lock joints of Type B gas vents Do not weld or fasten the vent pipe to the boiler draft diverter The weigh...

Page 8: ...ate valves at the boiler inlet and outlet so it can be isolated for service Check local codes for specific plumbing requirements before beginning the installation An ASME pressure relief valve is supp...

Page 9: ...Water Inlet Air Cushion Type Expansion Tank Optional Feed Water Inlet Air Scoop JV Boiler Zone Pumps must be sized properly Flo Checks Flo Checks installed at proper places Bypass Valves Feed Water I...

Page 10: ...he cooling cycle 1K Electrical Wiring Follow these instructions to make the necessary initial electrical connections 1 Remove the two screws attaching the front cover of the control box 2 There are fo...

Page 11: ...al Code Part 1 in Canada Do not rely on the gas or water piping to ground the metal parts of the boiler Plastic pipe or dielectric unions may isolate the boiler electrically Service and maintenance pe...

Page 12: ...lified electrical technician make the necessary measurements to properly set the thermostats 1L Filling the System It is crucial to the efficient operation of the system that all air be removed from t...

Page 13: ...For primary secondary pumping Connect to W in lieu of A Boiler relay is used for boiler pump and connection to W will energize boiler pump when any zone is calling for heat Wiring with Taco Zone Valv...

Page 14: ...m pressure with the boiler pressure gauge before beginning regular operation SECTION 2 Operation and Maintenance 2A 1 System Start Up WARNING Do not use this appliance if any part has been under water...

Page 15: ...n all the way and hold in Immediately light the pilot with a match using the match holder Continue to hold the control knob in for about one 1 minute after the pilot is lit Release knob and it will po...

Page 16: ...eratures are approximate 2C Maintenance 1 Lubricate the water circulating pump per the instructions on the pump 2 If a strainer is employed in a pressure reducing valve or the piping clean it every si...

Page 17: ...ge test the circuit between the red wire on the transformer and terminal 4 on the pump relay from terminal 6 on the pump relay and the A connection on the terminal board and from the purple wire termi...

Page 18: ...oiler of higher input 7 Pump noisy A Air in volute A Bleed air from volute Check pump alignment B Worn coupling or bearings B Replace worn parts 8 Boiler pounding A Too low water flow through boiler A...

Page 19: ...ble and ground wire Clean flame rod Check electrical connections between flame rod and module Check for cracked ceramic flame rod insulator Check that pilot flame covers flame rod and is steady and bl...

Page 20: ...or more interconnecting circulating loops each with its own pump Primary System Circuit Secondary Boiler Circuit Reverse return Piping Balanced equal flow first in last out piping Utilized with multip...

Page 21: ...6601 20036601 20036602 20036602 20036603 20036603 20036604 20036604 Temperature Pressure Gauge A0000100 A0000100 A0000100 A0000100 A0000100 A0000100 A0000100 A0000100 Pressure Relief Valve 30PSI A0069...

Page 22: ...036700 20036700 20036700 20036700 Terminal Strip E0098500 E0098500 E0098500 E0098500 Hi Tension Lead 10449515 10449516 Blocked Vent Switch E0121000 E0121000 E0121000 E0121000 Roll out Safety Switch E2...

Page 23: ...Mini Therm II Hydronic Boiler Page 23 Figure13 PartsIdentification Figure 13 Parts Identification...

Page 24: ...CA 93021 805 529 2000 FAX 805 529 5934 20 Industrial Way Rochester NH 03867 603 335 6300 FAX 603 335 3355 480 S Service Road West Oakville Ontario Canada L6K 2H4 905 844 8233 FAX 905 844 2635 www laar...

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