Installing insert, but chimney not fully clean?

[mattgordon23]

Hi everyone --

We're getting ready to install our VC winterwarm small insert into our masonry fireplace with a stainless steel liner. We had the chimney cleaned by a chimney sweep but he said it was "the worst he'd ever seen" and so we needed to use "CreAway" (a chemical lime-based product that loosens up glazed creosote) and have some big fires and then have him back to clean again. So we did all that, but when the sweep returned he didn't seem to do a very thorough cleaning job and said that our chimney is still pretty dirty, and that we could install the liner and the insert with the chimney as is, but he would have some more big fires and have it cleaned again first. I looked in the chimney myself from the ash clean out, and there is about 1/2" of glazed creosote buildup on the smoke shelf. The inner chimney walls don't look as bad, but they're still pretty black and there are areas of fluffy creosote that I could knock off easily with a small wire brush. Also, the chimney sweep didn't vacuum after the last cleaning because he said that since we'd had a fire within 24 hours in the fireplace, the warm debris would mess up his vacuum equipment (?). So the chimney was swept but not vacuumed out. Doesn't this mean that the chimney hasn't fully been cleaned? But I guess my larger question is: how clean does our chimney need to be in order to safely install our liner and insert? Won't the liner contain most of the heat, or at least enough so that any remaining creosote left on the chimney walls won't ignite? I don't have any info on the liner other than it's a used 6" stainless steel liner that came with the stove (got it all used).

Any help greatly appreciated.

thanks, Matt.

 

[cmonSTART]

Having a flue clean prior to installing a liner is pretty important for a couple reasons. First, after you seal off the flue with the liner in it sometimes creosote smell can back into the house which is fairly undesirable. Second, if you're installing the liner uninsulated it can transfer enough heat to light off a glaze accumulation. Bare liners are just thin metal so they do not "contain" heat very well. Properly insulating the liner will obviously reduce this risk though. It's always best to get the flue/fireplace as clean as possible. Power cleaning with chains will probably help, though some folks don't like doing it.

As for not vacuuming, if the fireplace was warm and used recently there is a risk of catching your vacuum and then truck on fire if you suck up a hot ember. It does happen.

 

[jatoxico]

+1 clean it first. Nows the time, stoves and liners run hot and can touch off residual creosote and unburned debris.

 

[begreen]

Without a doubt do it now. Just imagine what will happen if the captive creosote ignited.