364861-UIM-B-0708

SECTION IX: START-UP AND

ADJUSTMENTS

The initial start-up of the furnace requires the following additional procedures:

All electrical connections made in the field and in the factory should be checked for proper tightness.

When the gas supply is initially connected to the furnace, the gas piping may be full of air. In order to purge this air, it is recommended that the ground union be loosened until the odor of gas is detected. When gas is detected, immediately retighten the union and check for leaks. Allow five minutes for any gas to dissipate before continuing with the start-up procedure. Be sure proper ventilation is available to dilute and carry away any vented gas.

GAS PIPING LEAK CHECK

FIRE OR EXPLOSION HAZARD

Failure to follow the safety warnings exactly could result in serious injury, death or property damage.

Never test for gas leaks with an open flame. Use a commercially available soap solution made specifically for the detection of leaks to check all connections. A fire or explosion may result causing property damage, personal injury or loss of life.

Burner ignition may not be satisfactory on first startup due to resid- ual air in the gas line or until gas manifold pressure is adjusted. The ignition control will make three attempts to light before locking out.

It is recommended that when the gas supply is first connected to the furnace, the ground union be loosened until the odor of gas is detected. When gas is detected, immediately tighten the union and check for gas leaks. Allow five minutes for any gas to dissipate before continuing with the startup procedure. Be sure that proper ventilation is available to dilute and carry away any vented gas.

With furnace in operation, check all of the pipe joints, gas valve connec- tions and manual valve connections for leakage using an approved gas detector, a non-corrosive leak detection fluid or other leak detection methods. Take appropriate action to stop any leak. If a leak persists, replace the faulty component.

The furnace and its equipment shutoff valve must be disconnected from the gas supply during any pressure testing of that system at test pres- sures in excess of 1/2 PSI (3.45 kPa).

The furnace must be isolated from the gas supply piping system by closing the equipment shutoff valve during any pressure testing of the gas supply system.

IGNITION SYSTEM SEQUENCE

1.Turn the gas supply ON at external valve and main gas valve.

2.Set the thermostat above room temperature to call for heat.

3.System start-up will occur as follows:

a.The induced draft blower motor will start and come up to speed. Shortly after inducer start-up, the hot surface igniter will glow for about 17 seconds.

b.After this warm up, the ignition module will energize (open) the main gas valve.

c.After flame is established, the supply air blower will start in about 30 seconds.

CALCULATING THE FURNACE INPUT (NATURAL GAS)

Burner orifices are sized to provide proper input rate using natural gas with a heating value of 1030 BTU/Ft3 (38.4 MJ/m3). If the heating value of your gas is significantly different, it may be necessary to replace the orifices.

NOTE: DO NOT set manifold pressure less than 3.2 in wc or more than

3.8in wc for natural gas at sea level. If manifold pressure is outside this range, change main burner orifices.

NOTE: If orifice hole appears damaged or it is suspected to have been redrilled, check orifice hole with a numbered drill bit of correct size. Never redrill an orifice. A burr-free and squarely aligned orifice hole is essential for proper flame characteristics.

DO NOT bottom out gas valve regulator adjusting screw. This can result in unregulated manifold pressure and result in excess over- fire and heat exchanger failures.

Verify natural gas input rate by clocking meter.

1.Turn off all other gas appliances and pilots.

2.Run furnace for a minimum of 3 minutes in heating operation.

3.Measure time (in sec) for gas meter to complete 1 revolution and note reading. The 2 cubic feet dial provides a more accurate mea- surement of gas flow.

4.Refer to Table 9 for cubic feet of gas per hour.

5.Multiply cubic feet per hour by heating valve (BTU/cu ft) to obtain input.

If clocked rate does not match the input rate from the unit nameplate. follow steps in next section to adjust the manifold pressure. Repeat steps 2 - 5 until correct input is achieved.

Be sure to relight any gas appliances that were turned off at the start of this input check.

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Johnson Controls Unitary Products

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Johnson Controls TG9S*MP, GG9S*MP Section IX START-UP Adjustments, GAS Piping Leak Check, Ignition System Sequence
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TG9S*MP, GG9S*MP specifications

Johnson Controls has long been at the forefront of building efficiency solutions, and their TG9S*MP and GG9S*MP series exemplify this commitment. These two-stage, multi-position gas furnaces are designed for optimal comfort and performance in residential applications, and they come packed with a variety of features that enhance their efficiency and operational capabilities.

One of the standout features of the TG9S*MP and GG9S*MP furnaces is their efficient two-stage operation. This technology allows the unit to operate at a lower capacity most of the time, which translates into reduced energy consumption and costs. When the demand for heating increases, the furnace automatically shifts to a higher capacity, ensuring a consistent and comfortable indoor temperature. This flexibility not only enhances comfort but also extends the lifespan of the unit as it doesn't have to work harder than necessary.

Energy efficiency is a crucial characteristic of both models. With an Annual Fuel Utilization Efficiency (AFUE) rating of up to 96%, these furnaces convert a significant amount of the fuel they consume into usable heat. Such efficiency ratings not only help in reducing energy bills but also have a positive impact on the environment by minimizing greenhouse gas emissions.

Both models feature advanced technology in their design, including a fully modulating gas valve and a variable-speed blower motor. The modulating valve adjusts the gas flow in response to the thermostat’s signals, allowing for precise temperature control and improved comfort. Meanwhile, the variable-speed blower motor enhances airflow while operating quietly, significantly improving overall indoor air quality by promoting even heat distribution throughout the home.

From a structural standpoint, the TG9S*MP and GG9S*MP are built with durable materials designed for longevity. Their compact design allows for flexible installation options, whether in a closet, attic, or basement. The furnaces also come equipped with a robust heat exchanger crafted from high-quality materials, which ensures both reliability and efficiency.

In conclusion, the Johnson Controls TG9S*MP and GG9S*MP furnaces provide homeowners with efficient, reliable, and comfortable heating solutions. With advanced features such as two-stage operation, impressive AFUE ratings, and modern technology integrations, these models stand out in the market as dependable options for both energy savings and year-round comfort. Whether you're a homeowner looking to upgrade your heating system or a contractor seeking high-quality products for your clients, these furnaces represent a smart choice.
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