Before I Buy I have a few questions.

I am thinking of buying a HeaterMeter 4.3 and I see I have the option of getting one with just thermistors or one with a thermocouple. I have been reading through the forums and have seen quite a few posts about the difference and there seems to be a lot of opinions one way or the other. What is the true benefit of using a thermocouple over a thermistor?

I have also seen a few posts about automatic dampers but the post that feature the dampers don't really describe the purpose of why it is needed or atleast I am not understanding why they are used.

The fan & damper assemblies are used to control airflow into the firebox for precise heat control in the cook chamber. The HM can close the damper and stop the fan to drop the cook chamber temp, or open it up and used forced draft to heat up the chamber. It's not uncommon for a smoker with an HM to control pit temps to +/- 1 degree F. Without this assembly, the HeaterMeter is a temperature monitoring device.

So the damper just allows for more precise control? I am currently using a BBQ Guru CyberQ with my Big Green Egg and that has some temperature swings but not much it normally stays within a degree or two of my setpoint. But I normally have the damper on the fan mostly closed off. The HM should be able to control the temp of my BGE without the automatic damper right? I mostly do low and slow smoking at about 220 degrees F.

What about the thermocouple and thermistor conundrum?

Without a damper air can flow freely through the blower which limits the HM's ability to reduce the pit temperature. A damper can close off the air flow and greatly improve the HM's ability to lower the pit temp rather than just boost it with the fan.

Thermocouple VS Thermistor, a few differences there.

TC's are generally cheaper, withstand higher heat levels and are more durable in general. If you plan to use your HM for any high heat cooking (searing, pizza's etc) you definitely want to go TC, otherwise you will burn up a lot of thermistor pit probes... The negative to TC pit probe is the cost of the TC parts on the HM board and/or the SMD soldering of the parts if you DIY. Also, you must use special TC wire to extend the length of a TC probe, otherwise you can use the Aux Thermocouple board to extend the distance from the HM, also SMD soldering.

Thermistor pit probe is fine if you just do low and slow smoking.... before the TC was available I was using Maverick probes and seemed to burn through the pit probes fairly rapidly, my TC has been out on the grill for a couple years now... Lately I have been using Thermoworks Pro food probes and find them very reliable and durable, I do not cycle through them like I did with the Mavericks, however, their top end temp is even lower than the Mavericks so I only use them as food probes at cook temps under 500 degrees.

It sounds like it does what I have been doing with my BGE. When I am smoking I have the fan damper < 25% open and the top damper almost closed. Then the fan just has to force the air it and it doesn't just freely flow.

I think I'm going to buy the HeaterMeter 4.3 with the thermocouple and see if that works without the auto damper. If not I'll incorporate the damper.

Thanks for the answers.


--Sean

The top vent clamp down works pretty well on a good grill. Another benefit of the damper is you can open the top vent a bit more than systems without the damper and let things flow more freely... you can also run the system without the fan, just letting the damper control things, more like a normal cook where you adjust the vents, only the HM is adjusting the vent for you.

FWIW I use the servo/damper only, without a fan even installed, on my large bge for low and slows. Works great!

My thinking is that for low and slow on an efficient ceramic grill with such high thermal mass that a damper is all you need. If you're running at higher temps or a weber for low and slow I can see where a fan would be more useful.

I know it was user error but I once had an experience where the fan kicked up and deposited a nice layer ash all over my brisket. Not good eats.