Which Thermometer Should I buy?

.... Goto Lowes and get whatever one they have on the shelf for 14.99.

I recently bought thermometers myself. I bought the Chimgard first for about $30 after shipping. I then bought the Rutland stovetop for $7 at Menard's. Looking back, I'd have skipped the flue thermometer because it seems if the stove temp is in check the chimney is too. Oh well, I'm a stuff guy, so the more gadgets the better.

Not all Lowe's or Home Depot stores have thermometers. The stores around here don't carry stove thermometers.

karl said:

Not all Lowe's or Home Depot stores have thermometers. The stores around here don't carry stove thermometers.

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The stores by me don't have them, they do sell stoves and a few odd ball sections of stove pipe, but not everything you would need for a stove set up. Typical of the big box philosophy.

Stay away from Rutland, everyone I've had read high. I tested them in the oven and they were 75-100 high. Condar has some good ones.

As a primary how's-the-fire-doing measurement I prefer to measure flue temperature since it responds much more quickly -- in less than a minute -- to changes in the fire or draft. I use my flue thermometer to keep temps from spiking too high during the kindling burn, to set the burn rate (draft) for the heat output I want, to avoid over-firing, to decide when to re-load... and, when faced with a few coals in the morning, to decide how much and how small kindling I'll need to get things going again.

The problem is that the "flue temperature" thermometer widely sold at hearth shops is a hoax... it has an iron spike that sticks into the flue, but the actual measurement is effectively a bimetal coil doing a surface-temperature measurement on the flue pipe, calibrated to "estimate" the actual flue gas temperature inside. This is slow to respond and very subject to errors due to room air movement, placement, pipe wall thickness, etc.

Instead, take a look at these actual stem-type industrial thermometers:

Tel-Tru Industrial Dial Thermometer





They're USA made and you can order direct from the Tel-Tru site. (The model I linked is the 150-750 range that I use... they also have a 200-1000 range as well as a bunch of others.) It's accurate to a few degrees, fast responding, and measures what to my mind is the temperature you really want to know when operating your stove -- how hot is the fire.

regards,
Eddy

Todd said:

Stay away from Rutland, everyone I've had read high. I tested them in the oven and they were 75-100 high. Condar has some good ones.

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Are you sure your oven is calibrated correctly? I've had one oven 200 degrees off!

Although I am new to using gauges to moniter a stove, it seems in my case at least, that the stove top temp is not necessarily the best way to determine what is going on in the flue. For example, I have had average temp reads on my stove top gauge but if I have a lot of air coming in and therefore lots of flame, my flue temp reads much hotter (I presume because lots of hot air is excaping up the flue directly) than when I am doing a slower burn. Conversely, the stove top temp can be super hot right after I cut back the air and if I am using hard wood and the flue temp seems just fine.

And if you are a cook, it is prudent to have a thermometer inside your oven because as Ron B noted, ovens are often way out of whack...just try to bake bread or cake when your oven is not calibrated correctly! Just some observations from my experience.

kb

EddyKilowatt said:

Instead, take a look at these actual stem-type industrial thermometers:

Tel-Tru Industrial Dial Thermometer

Click to expand...

Can these be stuck in a chimney liner as easily as they can in stovepipe? They look pretty well-built.

Burn-1 said:

EddyKilowatt said:

Instead, take a look at these actual stem-type industrial thermometers:

Tel-Tru Industrial Dial Thermometer

Click to expand...

Can these be stuck in a chimney liner as easily as they can in stovepipe? They look pretty well-built.

Click to expand...

Not sure... I drilled for mine, into a 45 degree stainless elbow actually... then threaded the 1/8" NPT thread into the hole. A bit mickey-mouse but it has been there for three seasons now without budging. They are sturdy about like a meat thermometer is sturdy... you would not want to hammer them into anything.

Eddy

p.s. Be sure to remove before running a brush down the pipe. Don't ask me how I know.

i'm glad i saw this thread because i was going to start my own thermometer thread about how much they vary.
i happen to have three and at about the 700 degree range they all vary by 150 degrees! (between the three of them)

i have the Imperial which came from the local True Value hardware store and it read the highest by far (about 100 degrees higher than the others)
i also have an old Vermont Castings one that may have just been relabeled by another company not sure, its old.
my third, and favorite, is the Condar Medallion. seems to work well and looks good to boot!
bottom line though is i have no way to verify how good any of them are actually working.

i wish i had a digital instant read thermometer to test them all and post the results here.
if someone with one wants to do it i'd chip in a few bucks to the cause or donate my Imperial.

There is a note on that site TEL that says thermometers are to not be continously run at the high temps with the 200-1000 degree models :gulp:

the only one I have ever used is this non contact IR one from harbour feright.

https://www.hearth.com/econtent/index.php/forums/viewthread/10570/

I highly recommend it for stove use, you will learn alot about your stove!

Todd said:

Stay away from Rutland, everyone I've had read high. I tested them in the oven and they were 75-100 high. Condar has some good ones.

Click to expand...

UUUUMMMM.. so who sez your oven has an accurate reading?

I love to bake and cook.

Our gas stove thermometer/regulator is off about 20 degrees.

Did you over cook your Turkey last Thursday?

Man, I was thinking about a thermometer, but after reading all this, I'm not sure it's worth it. What with all the disagreement as to accuracy ... if it's not accurate I don't want it.

After burning since 1998 with the same stove (took it with me when I moved) by now I'm thinking "if I don't have it, I don't need it."
I don't know, I guess if you have no clue as to what you're doing, it's important. Or, if you're a pro but you like gadgets, fine. But if you're smart with good situational awareness I can't imagine overfiring and not knowing it's happening. I've cherried my flue once or twice (visible only in dim light) but that only happened when I wasn't paying attention after lighting, burning too much kindling, or I think once it was loaded with really small splits.

With a normal load of wood, I've never had a problem. You might say that without a thermometer I wouldn't know, but the thing's been around for 20 some odd years, plus I've had it apart and there are no cracks.

The other thing I was thinking was, some of you live in COLD COLD COLD climates. The one guy said he takes his heater within 50* of the max temp.
Where I live, we really don't know from cold. Maybe if it below zero here I might need to worry about this issue more.

I bought a 15 dollar Condar Chimgard Model 3-4. It works fine. Is it accurate? Who knows, but at least you have a reference point and it didn't break the bank. It's better than guessing.

There is a new thermometer from Condar called the Inferno that says it's calibrated specifically for stove top use. They sell on Amazon, but it's cheaper to buy from their web site.