A fireback gets hot when a fire is burned in the fireplace and slowly cools off again when you are not burning a fire. After a few weeks with no fire, the fireback will be completely cooled. If you again build a fire after a period of a few weeks or longer without a fire, then it is important that your first fire be a moderate fire. This is to prevent the fireback from cracking due to rapid temperature changes. We call this thermal shock. Thereafter, you can build larger fires.
Other precautions against thermal shock:
- -Do not burn coal or tropical hardwood if you have a fireback in the fireplace. The fire can then get too hot.
- -Never put the fire out with water.
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