Question: Hello. I have a 4year old Dutchwest Convection Heater, the large model 2461, which has a 2year old cat converter. The baffle (waffle like shield) underneath the cat is coated and almost plugged up with bright orangish-red crumbly deposits.I have had to use a brush and a pipe cleaner on the baffle to get the deposits off so my stove can breathe again. I believe they are part of the reason my stove was somewhat sluggish last year. There are a few (almost none in comparison to those on the baffle) deposits on the bottom of the cat. I intend to use the distilled water/vinegar cleaning procedure on the cat before using the stove this winter. I have just regasketed the stove, and recemented the seams. The orange-red deposits have my stove shop people totally baffled, as they have allegedly never seen this on any brand cat stove. One of the employees said the deposits were evidence the cat was properly working. What is your take on the deposits? I have not burned any plastic or colored print in the stove. I am concerned that perhaps the cat is degrading and need s replacement due to these deposits. Thanks. Answer: Well, let's teach those stove shop employees a thing or two. The orangish-red crumbly deposits are actually the cast iron of the baffle which has been overheated. When I say overheated, I do not mean that you did anything wrong. The cat and stove can become very hot and create temperatures which almost reach the melting point of iron. Repeated heating like this can cause cast-iron to actually swell and break apart into flakes. The color is always an indication of this. We see this a LOT on coal stoves, but somewhat less on wood stoves. The deposits on the bottom of the cat are probably pieces of the same which have been sucked up into it by the draft. Replace the part if possible. The part is simply a flame diffuser which spreads the fire and smoke out so it uses as much of the cat as possible.