Gas Furnace and the Heat Exchanger. Your furnaces heat exchanger is the most valuable part of your furnace. The heat exchanger creates the separation of harmful gases and the warm air used for heating. The four main problems encountered with heat exchangers are Rust, Cracked, Clogged and Overheating.
Rust – This is by far the most common problem found with heat exchangers. Air conditioners and humidifiers mounted above the heat exchanger are two of the major causes of rust creation. A leaking air conditioner drip tray, a condensate line leak, both of which can cause rust and eventual failure of your heat exchanger. Humidifiers are by far the most common source of rust in your furnace. Cheap design and hard water, coupled together, create the perfect match for allowing moisture and water into your furnace. The common drum humidifier which rolls through a tray of water, the level of which is controlled by a float, commonly gathers calcium and other hard water particles, which then causes the float to fail and water enters your furnace. The majority of humidifiers I inspect have no inside parts and the water line has been disconnected or turned off. The cold air return plenum usually has signs of water leakage from the humidifier down to the furnace. This is always an indication that a furnace technician should be called in to throughly inspect the heat exchanger. A visual inspection can not be relied on to detect all possible damage and partial dismantling of the furnace is usually required.
Cracked – Furnaces can be damaged by careless shipping or by being dropped by the installer. This can lead to a cracked heat exchanger that would not be visible to the naked eye or casual visual inspection. High temperatures can also cause cracks in the heat exchanger or maybe a faulty casting or fault in the alloy.
Clogged – This condition is usually caused by accumulation of condesate or soot. Having flue passages cleaned in high efficiency furnace heat exchangers can be a very expensive process.
Overheating – One of the common causes of overheating is the lack of air flow across the heat exchanger. Having a new furnace installed without ensuring adequate duct sizing is a common cause of this problem. Always ensure work is done by competent technician who will ensure duct size and fan blower is adequate for the furnace being installed.
Regular Maintenance will prolong the life and efficency of your furnace. Annual maintenance is the least recommended time span between cleaning and tune-ups. Save your self money and un-needed agravation by having your furnace seviced by a qualified professional.
CAVET EMPTOR – BUYER BEWARE
BROUGHT TO YOU BY THE ALLISTON HOME INSPECTOR