Gas cooktop slowness

[Chas]

About 10 years ago I installed a natural gas 4 burner cooktop. It works fine except the biggest burner takes forever to heat 3 qts of water. I still have my old electric cooktop hooked up (in a free standing cabinet), and with a 7" round burner it heats that much water in 1/5 that time. At installation, I installed a 1/2oz gas regulator on my cooktop and I am pretty sure the local utility company furnishs natural gas at 1/2 oz after the meter. Anyone have any idea how I can generate more heat from at least one of my gas burners? Without purchasing another unit. I have been looking for a 1500W electric burner that I can use to replace one of the gas burners my gas cooktop. I have the tools and time to do this. Else I could accept a 1200+Watt self standing electric burner...can't find one yet and I am unfamiliar with the induction types, which I understand do not work with Aluminum\ . in appreciation, thanks to one and all who may be able to provide assistance. . .chas

[Tony Hwang]

Hi, Do you live at high altitude?

[Joe]

Call the gas company and get a pressure check. As mentioned above, undersized supply lines will be a problem. Finally, when the pressure is right and flow is to specs, adjust the air inlets to the burners. A big fluffy yellowish flame doesn't have much heat. Nice, sharp blue cone flames are the maximum in any gas appliance, even welding torches.

Joe

[George]

What was the reason for the second regulator? I think you might have units mixed up but if the gas companies regulator is already at the pressure setting of the second regulator what was the reason for the second regulator which is also a restriction? NG pressure is typically measured in inches of water column with ~ 6" WC being typical.

You could get the nameplate rating of the burner and making sure no other devices are using NG burn it for a length of time and record usage on the meter and see if it is producing the correct output.

[trader4]

You can also build a u-tube manometer to measure pressure that's very accurate out of a piece of clear plastic tubing, water, some food coloring and a piece of wood.

[mike]

I haven't had a gas stove in 40 years, but I can give you some diagnostic guidance.

Light the big burner and turn it up high. Note the size of the flame. Light the other three burners. If the flame height doesn't change, you don't have a restriction problem.

Do some math. Six BTU's will heat your 6 pints of water one degree F. Depending on where you live, you may have to convert some of the units. You'll need to be more precise than "forever". Compare that to the spec of the burner. If you can't find the spec, you should be able to find specs on a similarly sized burner. If you're getting less heat than spec, you need more gas pressure.

I'd call the gas company. It may take some pleading to get past the robot in the call center, but the engineering department can give you some advice about pressures. They may even come out and measure the pressure for free.

I don't have any specific knowledge about your pressure regulator, but in general, if you expect to get 1/2oz out, you need to have more than 1/2oz in. Something has to press on that regulator spring. Why did you install it in the first place? Two regulators in series at the same pressure may be your problem. You may not be able to tell with a static pressure test. You may need to have the gas flowing.

I'd never recommend anybody mess with a gas stove themselves. It would be really sad to create a leak that blows up your house. Or get the flame too big and gas yourself with CO.

Are we having fun yet?

[Chas]

. . .First, thanks to 1 & all for the help.

I live at 5300 feet above sea level. I lose probably 16 percent >> About 10 years ago I installed a natural gas 4 burner cooktop. It works

[mike]

16% is hardly enough to be described as "takes forever".

Somebody correct me if I'm wrong... Gas, when completely combusted, releases a certain amount of energy per unit of mass. At high altitudes, the volume will be greater and more air will be required to get the proper amount of oxygen for optimum combustion. So, the volume of combustion products will be greater and pass by the pan at a greater velocity. Heat transfer will be somewhat less efficient.

If a therm is 100K BTU, you should be able to get about the same amount of energy out of a therm no matter what the altitude.

Is your stove designed for high altitude use? The geometry may be different for a high altitude unit, orifice sizes etc.

Do you not know anybody else who cooks with gas and can compare notes?

[micky]

Not a pressure problem before the second regulartor, but what about afterwards? I don't think the extra-burner/ HWH/Furnace test eliminates that, since the flames have been tuned for use with both regulators.

Do you have neiigbors at your altitude, or higher?. Take your pot to their house and see how long it takes to boil the water there. Make them a spaghetti dinner if they seem ambivalent.

More than one house if necessary.

It's a good way to meet the neighbors. When I moved into my apartment, I dint' have a phone so I used the phone of two n'bors. Even after they connected the phone, I pretended I didn't have one and met the other two that way.

[Pete C.]

Before you blame the cooktop, you have to understand that while gas burners allow rapid adjustments in the flame and may have high BTU/hr ratings, they are much worse than electric "burners" at actually transferring the BTUs produced to the cooking pot or pan. A great deal of the BTU output of a gas burner just flows around the pan and past it heating the kitchen, not the pan.

Choosing the largest burner thinking that it will heat the water fastest may actually be doing the opposite since the larger burner diameter relative to the pan allows more of the heat to bypass the pan. Do a controlled test of time to boil using the same pan at the same starting temperature, both on the largest and smallest burners. Quite possibly you will find that the water boils faster on the smaller burner due to better heat transfer.

Another option is a standaline electric "burner", or a dedicated electric boiling water pot. If you go that route, get a quality "burner" not from China (see a restaurant supply store), or a European brand electric water pot (more common there). I wouldn't try to modify the existing cooktop, that would create all manner of safety and insurance issues. You can however buy a dual fuel cooktop, but they are high end and expensive.

[nonon]

In Israel and Europe these are called kettles, and I've heard the selection is limited in the US. But you only need one.

[Han]

[e-mail] wrote in news: [e-mail]:

The electric teakettle is one idea, but a more genral one would be a single burner induction cooktop. Induction has to be the most efficient and safest way to use electricity to heat a pot. It's just that the pot has to be iron or at least a material that attracts a magnet, and you have to have

120 V AC current. See this:

[HeyBub]

My granny often said: "A watched pot never boils."

Maybe if you quit watching the pot, it would boil quicker?

[notbob]

You might check to see if your range company provides different burners (hobs) for your range, although 7" seems pretty large. Perhaps larger holes, more flow, etc. I the gas range of one of my neighbors has two different size burners, one larger than the other, which heats much quicker.

nb

[Chas]

************************************************* When I installed my new efficient forced air furnace I had the seller furnace me with the high altitude orifices. They were actually smaller than the sealevel ones as there is less oxygen up here.. . .hence the 16 pecent reduction in the output.. . chas

[gregz]

You should be able to look at the flames and judge looking at other cook tops.

Greg

[Ed Pawlowski]

Increased pressure at the meter would make no difference, summer or winter. Once you have adequate flow, gas is limited by the orifice. It will not burn any more, winter or summer, in any appliance. A cubic foot of gas contains a given amount of energy and it will give it up when burned. Your heater will have a regulator that will keep it from too much pressure.

[mike]

It is possible to do some simple math. According to your numbers, the heat value from your burner into the pot is 300W. According to google, gas has 70ish percent of the transfer efficiency of an electric burner. That gets you to 428watts worth of gas.

Again, according to google,

All types of burners made for gas cooktops output different levels of heat, which is measured in BTUs. Standard gas burners will put out approximately 8,000 to 10,000 BTUs of heat. Heavy-duty gas burner varieties found in commercial kitchens may put out heat up to 18,000 BTUs

If I have my math straight, your 428W is equivalent to a burner rating of 1450 BTU.

Something is not right.

[micky]

Good point.

I havent' been watching his pot. Maybe it's boiling now.

[Stormin Mormon]

On furnaces, the gas pressure to the orifice is limited by the gas valve (I think 3.5 inches WC). The orifice can deliver more or less, depending on gas valve setting. Or, also can be limited by spiders nest in the orifice, as I found one time.

As for the OP, calling the gas company for higher pressure isn't likely to improve the stove performance. With a flame that maintains when other burners are on, and flame is a good blue. Might be that's how the stove is supposed to work.

Christopher A. Young Learn more about Jesus

.

Increased pressure at the meter would make no difference, summer or winter. Once you have adequate flow, gas is limited by the orifice. It will not burn any more, winter or summer, in any appliance. A cubic foot of gas contains a given amount of energy and it will give it up when burned. Your heater will have a regulator that will keep it from too much pressure.