![Other Unit Adjustments](/images/new-backgrounds/35449/3544991x1.webp)
Testing for Proper Venting and Sufficient Combustion Air for Non−Direct Vent Applications
WARNING
CARBON MONOXIDE POISONING HAZARD!
Failure to follow the steps outlined below for each appliance connected to the venting system being placed into operation could result in carbon monox- ide poisoning or death.
The following steps shall be followed for each ap- pliance connected to the venting system being placed into operation, while all other appliances con- nected to the venting system are not in operation.
After the G61MP gas furnace has been started, the follow- ing test should be conducted to ensure proper venting and sufficient combustion air has been provided to the G61MP, as well as to other
If a G61MP furnace replaces a Category I furnace which was commonly vented with another gas appliance, the size of the existing vent pipe for that gas appliance must be checked. Without the heat of the original furnace flue prod- ucts, the existing vent pipe is probably oversized for the single water heater or other appliance. The vent should be checked for proper draw with the remaining appliance.
The test should be conducted while all appliances (both in operation and those not in operation) are connected to the venting system being tested. If the venting system has been installed improperly, or if provisions have not been made for sufficient amounts of combustion air, corrections must be made as outlined in the previous section.
1 − Seal any unused openings in the venting system.
2 − Visually inspect the venting system for proper size and horizontal pitch. Determine there is no blockage or re- striction, leakage, corrosion, or other deficiencies which could cause an unsafe condition.
3 − To the extent that it is practical, close all building doors and windows and all doors between the space in which the appliances connected to the venting system are lo- cated and other spaces of the building.
4 − Close fireplace dampers.
5 − Turn on clothes dryers and any appliances not con- nected to the venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, so they will operate at maximum speed. Do not operate a summer exhaust fan.
6 − Follow the lighting instruction to place the appliance being inspected into operation. Adjust thermostat so appliance will operate continuously.
7 − Use the flame of match or candle to test for spillage of flue gases at the draft hood relief opening after 5 min- utes of main burner operation.
8 − If improper venting is observed during any of the above tests, the venting system must be corrected or
sufficient
9 − After determining that each appliance remaining connected to the common venting system properly vents when tested as indicated in step 3, return doors, windows, exhaust fans, fireplace dampers and any other
Other Unit Adjustments
Primary and Secondary Limits
The primary limit is located on the heating compartment vestibule panel. The secondary limits are located in the blower compartment, attached to the back side of the blow- er. These limits are factory set and require no adjustment. Flame Rollout Switches (Two)
These manually reset switches are located on the burner box. If tripped, check for adequate combustion air before resetting.
Pressure Switches (Two or Four)
The pressure switches are located in the heating compart- ment on the combustion air inducer. These switches check for proper combustion air inducer operation before allow- ing ignition trial. The switches are factory−set and require no adjustment.
Back−Up Secondary Limit (090, 110 & 135 Models) The back−up secondary limit is located on the combustion air inducer. This switch protects the plastic components from overheating due to indoor blower motor failure. If tripped, check for proper blower operation before resetting. Temperature Rise
After the furnace has been started and supply and return air temperatures have been allowed to stabilize, check the temperature rise. If necessary, adjust the blower speed to maintain the temperature rise within the range shown on the unit nameplate. Increase the blower speed to decrease the temperature. Decrease the blower speed to increase the temperature rise. Failure to do adjust the temperature rise may cause erratic limit operation.
Thermostat Heat Anticipation
Set the heat anticipator setting (if adjustable) according to the amp draw listed on the wiring diagram that is attached to the unit.
Electrical
1 − Check all wiring for loose connections.
Page 46