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Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

(OP)
Hey all,

For reasons I won't go into beyond saying they were renovation-related, our residential Canadian-made Pacific Energy brand fireplace insert hasn't been used for about five years.

When the unit was taken out of service at the time renovations commenced, I noticed some of the sections of the unit's firebrick had either sustained spalling, had cracks, or were missing chunks, so I ordered a complete replacement set of firebrick and swapped it all out [ I retained any complete old pieces, just in case ]. It is the new firebrick that has never seen heat I'm concerned about damaging.

My boiler books talk about building light fires in green refractory so as to both cure it and drive out any moisture before imposing full service duty. I'm wondering if I should do the equivalent...

My approach would be fabricate a heating unit using one of those screw-in ceramic cones wound with - what? Nichrome wire? - along with an older ceramic lamp socket and a supply cord utilizing Pyrotenax, if that's the right word, or some sort of equivalent high-temperature-compatible insulation, wired in series with an SCR-type lamp dimmer to regulate the heat output. I would use this rig to attain and stabilize the internals of the insert at a temperature of, say, 250 °F for, say, two or three days; temperature to be confirmed with a thermocouple-type pyrometer.

Two questions:

One, do I even need to worry about this?

Two, if I do, is the approach sensible, or would there be a better way to go?

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Pyrotenax may be overkill. Check The CEC, Table 19; conditions of use and maximum allowable conductor temperature...
Look also at table DD1. Check the end notes for temp ratings.
eg: SEWF-1 with a nickel conductor 250 deg.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

(OP)
Thanks, Bill; I didn't think Pyrotenax was the right stuff, hence my hesitation to use that word, but the name of what I had in mind had escaped me. I'll check the sources you suggest.

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

I see no need for a post-factory "cure"... most fireplaces sit in a factory warehouse for many months (often years) before being placed into service, not to mention they spend 6+ months of every year unused and sitting in the open air.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

(OP)
I take your point, MacGyver, and thanks; I hadn't thought of that...

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

(OP)
Hmp; may I should consider this a fresh start and do what the manual for ours recommends . . . [blush]

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Firebrick, as purchased, are not in the green condition. They have been fired during manufacture. As others mentioned, if there is any doubt as to moisture content, start out with a low fire to drive out any residual moisture.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

A small fire is what I've seen too. The steam will leave without breaking the brick if it isn't rapidly evolved.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Crshears,
I have not seen Pyrotenax in years. I did not even know it was still available. I can tell you horror stories of working with a blow torch on the open end of that stuff trying to get it to pass a Megger test before we potted the ends.
B.E.

You are judged not by what you know, but by what you can do.

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

berkshire. Did you ever get a coil of Pyro with a warning label attached?
"Warning. If a flame is used to dry this cable, care must be taken that the copper jacket is not melted."
I haven't seen the inside of a commercial gasoline pump for many years. They were originally wired in rigid conduit and explosion proof fittings.
This forced electricians to a level of precision that was above normal. Close enough was no longer good enough.
Then prefabricated Pyrotenax pigtails came on the market. No more precision measuring and cutting. Screw a seal fitting and an EX-P JB onto the end of the entering conduit and then bend the Pyro pigtail to fit between the incoming JB and the pump JB. Those pigtails saved several hours.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Yes I remember that warning, and trying to do a concentric earth/ground by soldering a pigtail to the outer jacket.
All of that stuff was 40 years ago.
B.E.

You are judged not by what you know, but by what you can do.

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Yeah, it's still very much available, and despite strong efforts from the manufacturers of polymer-insulated cables to incorporate mica and similar materials into their cables, Pyro is still the standard to beat terms of fire performance. Pyro is an absolute pig of a material to work with; those who can install it and make it look good have my admiration. There is/was a nickel variant of Pyro for aggressive environments, rather than the usual copper, which took the 'pig to work with' problem to another level. I believe the parent company is now Pentair, having originally been BICC.

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Scotty,
The stuff I worked with before I left the UK ( I used to help out my Dad who was an electrical engineer.) was made by British Insulated Callendars Cables.
And you are right about working with it, You got one shot at making a decent looking 90* bend , and to make things worse most of the stuff I put up was surface mounted.
B.E.

You are judged not by what you know, but by what you can do.

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

(OP)
Include one word you shouldn't have in a post and the whole thing goes south.... bigsmile

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Take a look at the element in the oven of your kitchen stove. See how the element passes out of the oven so that the connections are made at the cold end of the element. (ps; the construction of most oven elements is similar to the construction of Pyro)

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

(OP)
I got Pyrotenax mixed up with something else; the way Bill described the appearance of that stuff suddenly reconnected some synapses for me, and I now recall from years back that PT was used in the wiring to the lube oil centrifuges I used to operate way back in the day.

BTW I wanted to add a self-castigating emoji/emoticon to my previous post, but couldn't find the right head-bashing one I saw [in another thread] in the emoticons feature of the Post Options; are these alternate emojis being imported from another app?

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

(OP)
Looked at the manual for the insert; it is completely silent on starting small the first time...

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Returning Wood-Fueled Fireplace Insert To Service: Moisture In Refractory A Concern?

Ahh.... RTFM; Read The Fire Manual. I always wondered what those letters stood for. grin

Bill
--------------------
"Why not the best?"
Jimmy Carter

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