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Time for a rebuild? Maybe.

Time for a rebuild? Maybe.

Photo of furnace base with cracked insulation

Furnace base insulation…time to replace?

Furnace interior showing damage to base insulation layers

Note cracking in bottom insulation layers

Picture of furnace roof showing cracking of insulation

Note cracking in furnace roof

Furnace roof showing cracking in insulation running under anchors

Note the cracking in the furnace roof, including under the anchors



















No one wants to unnecessarily invest down time, money, and labor into replacing furnace parts. But avoiding even higher costs and longer furnace down time due to catastrophic failures should also be of paramount importance. Catastrophic failures, such as collapsed roofs, may result in total loss of insulation, elements, and yes, product in process.

Determining what parts need replaced and when can be a challenge. You can visit the Maintenance Guides section on our Tutorials page for guidelines on inspecting and maintaining your furnace. However, if you are unfamiliar with what’s caused by normal wear and tear vs what is a threat to furnace integrity and performance, making the right call can be difficult.

Please don’t hesitate to ask Deltech technical support for assistance. That’s what the customer who sent the pictures you see below did: asked for advice. They were concerned about the cracking, fearful of disaster if they operated the furnace at high temperatures.

We recommended against a rebuild and continuing to high fire. Our reasoning: The lining was overall in good condition and not allowing heat loss.  Roof cracking is a normal occurrence with insulation materials and is controlled by the roof anchors.  The ledge cracking is normal and acts as an expansion joint.

More marked damage and deterioration would likely have resulted in a different recommendation. But it’s important to note that parts can be replaced as needed, thus often obviating the need for a total rebuild.

See an example of a catastrophic failure and read about the cause. The insulation shows significant loss of integrity including severe shrinkage from exposure to overtemperature conditions.

For a less obvious case, view the following picture of a furnace roof exhibiting considerable sagging and layer separation. In this case, the damage was too great to repair and shore up with anchors. Replacing the roof was the best course of action to avoid roof collapse and loss of heating elements, damage to other parts of the furnace, and product loss.

Photo of furnace with crack

To show a furnace that needs a rebuild

Time for a rebuild. The furnace door is failing and there is extensive interior damage

Contact us for advice, assistance, and replacement parts.

Time for a rebuild? Maybe.

All Deltech furnace systems are designed and manufactured in the U.S.A, and shipped and installed worldwide.