Question about relationship between flame height and BTU output

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Clinton114

New Member
Feb 13, 2018
1
Virginia
In December 2017, I purchased new a set of replacement gas logs/burner for my house. Small set of logs, 18", supposed to be variable flame with a remote control. The brochure states that I could "Adjust the flame height from a low glow to a roaring fire or any comfort level in between." Well, during first use, the flame height would not adjust with the remote (not possible to adjust it manually). The burner goes from "off" to "roaring fire" in 0.5 seconds flat. I tried to get the installer to do something about it, but he denied there was a problem. He claimed that although the flame height didn't change, the BTUs changed when I press "hi/lo" on the remote. Now, I'm not an expert with gas burners nor do I have any education in thermodynamics, but my layman's assumption is that there's a direct relationship between height of the flame and BTU output. I called BS on the installer's defense of the product. At the "roaring flame" height, the room quickly becomes overheated regardless of pushing the "hi/lo" button on the remote.

Fortunately, the salesman looked at the video I provided and agreed there was a problem. Within 6 weeks he sent the installers back with a different unit (same model). This second set performs exactly the same as the previous set - from off, to roaring flame, when you press the "on/off" button on the remote, with no change in flame height when clicking the "hi/lo" button. Again I provided the salesman a video and again he agreed there is a problem. This time, however, the manufacture is pushing back with the defense that "BTUs will adjust with no change in flame height".

Before I go off the reservation and tell them what I think about their explanation (that essentially, I just don't understand how things work and it's my problem not theirs), I'd like to get someone's opinion on the question - is it possible that the BTU output would actually change when there is no visible difference in flame height/color? I'm not going to accept a set of gas logs that won't adjust to a romantic low glow regardless of the answer, but it might prevent me from making an ass out of myself if I argue with them on whether the BTUs actually change despite no change in flame height.

Please note I'm purposefully not naming the manufacture brand, as I don't believe it's relevant to the question. Thanks in advance
 
You are correct. When you turn the regulator UP, the gas flow is increased, the flames go higher because more gas is burned...
More gas burned = higher BTU output. More BTU output = more HEAT.
The MFR is giving you a line of crap..
.The unit PROBABLY uses a "stepper" type valve which incrementally increases the gas flow at each "step."
Apparently, the design is faulty...
 
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