Why would a heat exchanger fail?
Why would a heat exchanger fail?
A common reason your heat exchanger will fail can simply be a dirty, clogged air filter. A clogged air filter restricts airflow through the furnace and overheats the heat exchanger, which eventually results in stress cracks. An over-sized furnace can also cause overheating and crack the heat exchanger.
How to prevent heat exchanger failure?
Failures due to thermal expansion of fluids are most common in steam-heated exchangers. To help prevent failure due to thermal expansion and cycling, relief valves can be installed in the heated fluid system. It also is advisable to provide some means to absorb fluid expansion.
How to prevent corrosion on the heat exchanger?
Heat exchangers can be repaired using cold applied metal repair composites and epoxy coatings that will not only rebuild heat exchangers’ components to their original profile, but will also: Provide long-term erosion and corrosion resistance.
How much is a new heat exchanger?
The cost of replacing a heat exchanger ranges from $2,000 to $3,500. Replacing your furnace’s heat exchanger would be a good route to take if your furnace is fairly new. However, it is not worth spending your money on replacing your heat exchanger when it is near the end of its life span, which is ten years or more.
How can I improve my heat exchanger?
The method to increase the logarithm mean temperature difference of heat exchanger is to adopt counter current or near counter current mixed flow pattern as far as possible, increase the temperature of hot side fluid as far as possible, and reduce the temperature of cold side fluid.
What are problems in heat exchanger?
3 Common Heat Exchanger Problems
- Rust and Corrosion. Heat exchangers can corrode and rust out due to excess condensation inside the furnace.
- Age-Related Deterioration. Furnace heat exchangers are designed durably to withstand repeated cycles of heating up and cooling down over a long service life.
- Premature Metal Failure.
What are the disadvantages of plate heat exchangers?
Disadvantages
- Initial cost is high since Titanium plates are expensive.
- Finding leakage is difficult since pressure test is not as ease as tube coolers.
- Bonding material between plates limits operating temperature of the cooler.
- Pressure drop caused by plate cooler is higher than tube cooler.
How do you increase fin effectiveness?
Since the fin efficiency is inversely proportional to Λ, it can be improved either by increasing k and B, or by decreasing 〈h〉 and L. If the average heat transfer coefficient, 〈h〉, is increased due to an increase in the air velocity past the fin, the fin efficiency decreases.
What are the problems associated with corrosion in heat exchangers?
Heat exchangers may be subject to various modes of deterioration associated with flow such as erosion- corrosion, fretting, and fatigue, and they may suffer stress corrosion cracking (SCC) due to preexisting or imposed stress.
What is pitting in heat exchangers?
Pitting of Tubes Chemically-induced corrosion can result in the pitting of heat exchanger tubes to the point where pinholes form and the tube fails and leaks. Pitting results from the electrochemical potential set up by differences inside and outside of, what is commonly referred to as, a concentration cell.
