Lochinvar 497 - 2067 service manual Masonry chimney installation, Inspection of a masonry chimney

2 Venting (continued)

Common venting systems may be too large when an existing unit is removed.

At the time of removal of an existing appliance, the following steps shall be followed with each appliance remaining connected to the common venting system placed in operation, while other appliances remaining connected to the common venting system are not in operation.

1.Seal any unused opening in the common venting system.

2.Visually inspect the venting system for proper size and horizontal pitch. Make sure there is no blockage or restriction, leakage, corrosion and other unsafe conditions.

3.If possible, close all building doors and windows. Close all doors between the space in which the appliances remaining connected to the common venting system are located and other building spaces.

4.Turn on clothes dryers and any other appliances not connected to the common 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.

5.Close fire place dampers.

6.Place in operation the unit being inspected. Follow the lighting instructions. Adjust thermostat so unit will operate continuously.

7.Test for spillage at the draft hood/relief opening after 5 minutes of main burner operation. Use the flame of a match or candle, or smoke from a cigarette, cigar or pipe.

8.After making sure that each appliance remaining connected to the common venting system properly vents when tested as above, return doors, windows, exhaust fans, fireplace dampers and other gas burning appliances to their previous conditions of use.

9.Correct any improper operation of the common venting system so that the installation conforms to the latest edition of the National Fuel Gas Code, ANSI Z223.1, in Canada, the latest edition of CAN/CGA-B149 Installation Code for Gas Burning Appliances and Equipment. When resizing any portion of the common venting system, resize to approach the minimum size as determined using the appropriate tables of the latest edition of the National Fuel Gas Code, ANSI Z223.1, in Canada, the latest edition of CAN/ CGA-B149 Installation Code for Gas Burning Appliances and Equipment.

Installation & Service Manual

Masonry chimney installation

A masonry chimney must be properly sized for the installation of a high efficiency gas-fired appliance. Venting of a high efficiency appliance into a cold or oversized masonry chimney can result in operational and safety problems. Exterior masonry chimneys, with one or more sides exposed to cold outdoor temperatures, are more likely to have venting problems. The temperature of the flue products from a high efficiency appliance may not be able to sufficiently heat the masonry structure of the chimney to generate proper draft. This will result in condensing of flue products, damage to the masonry flue/tile, insufficient draft and possible spillage of flue products into an occupied living space. Carefully inspect all chimney systems before installation.

CAUTION	Venting of high efficiency appliances into a
	masonry chimney without a sealed stainless
	steel liner can result in operational and safety
	problems. Any breaks, leaks, or damage to
	the masonry flue/tile will allow spillage of
	the positive pressure flue products from the
	chimney. These flue products can easily
	escape into an occupied living space causing
	a health hazard. If there is any doubt about
	the condition of a masonry chimney, or
	its acceptability for use after insertion of
	a corrosion resistant liner system, consult
	with local code officials.

Inspection of a masonry chimney

A masonry chimney must be carefully inspected to determine its suitability for the venting of flue products. A clay-tile- lined chimney must be structurally sound, straight and free of misaligned tile, gaps between liner sections, missing sections of liner or any signs of condensate drainage at the breaching or clean out. If there is any doubt about the condition of a masonry chimney, it must be relined with a properly-sized and approved chimney liner system.

Vertical vent termination clearances and location

Follow all vertical venting termination information for clearances and location under Vertical Vent Termination Clearances and Location, page 16.

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