Question about Mr. Heater MH12CS with Electronic Spark Ignition Heater

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Heater wont stay lite

I flip the switch and it lights and works for 10-20 seconds and the flame goes out the fan stays on

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Re: heater wont stay lite

Needs a service, make sure there is no dust between the thermocouple and the pilot assembly. An air compressor should do it.

Posted on Dec 04, 2013

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Re: heater wont stay lite

Can you give us a brand name and model number?

Posted on Jan 18, 2008

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1 Answer

Goodman furnace gmh95090cxac wont stay lit keeps clicking will lite then clicks back off what would be the problem

Hello, if the burners light but do not stay on for more than 10 seconds, I would clean the flame sensor. The flame sensor is a metal rod that is on the opposite side of the Igniter, sometimes it gets coated by oxidation and does not sense the burner flame and shuts the Furnace down. To clean to kill power to tje furnace, remove flame sensor and clean with a steel wool, then reinstall and start Furnce back up. If this does not work then most likely the Igniter is too weak to ignite the gas and will have ro be replaced.

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Goodman Dependable 92, ignitor and fan comes on for 3 seconds, furnance does not turn on. Goes through 3-4 cycles, then shuts down furnance. If it is the flame sensor, where can one buy parts?

Do the burners come on? If so then yes it probably is the flame sensor if not then there is another issue not the flame sensor. The flame sensor could just be dirty take the flame sensor out and clean it with a piece of emery cloth or lite sand paper and put it back in and this should get the burners to stay on.

Feb 05, 2010 | Goodman GMS90703BXA Heater

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Pilot lites; but, as soon as I turn on gas flame

sounds like your thermacouplar is going out and needs replaced. Sometimes these will act like they are working fine , but when the pilot stays on for awhile and later goes out it is a sure sign that it is bad

Nov 08, 2009 | Procom ML300TBA Heater

1 Answer

Pilot light

Hi the thermocouple is a long copper wire that goes back to the gas valve from the pilot .

i would clean the flame senser first , then check the pressure switch jump this out , then check the fan control or snap disc jump this out see if it runs if you need A THERMOCOUPLE then honeywell universal will do

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The heater won't stay lit


Jan 16, 2009 | Desa International CBN20T Heater

1 Answer

I have a propane reddi heater and I can't get it to stay on after I light it, it won't stay on. Is there something that needs to be cleaned or replaced

Generally speaking a propane heater stays lite because the pilot stays lite. The pilot flame touches a thermocouple which produces a current which keeps the main valve open. Pilot goes out or you have a bad thermocouple or the pilot is slightly clogged (reduced heat to thermocouple) or maybe the thermocouple is not touching the flame enough. Most times when a propane heater goes out the problem is somewhere in that neighborhood. Thermocouple - pilot. I have always had luck carefully taking those parts off, cleaning, and reassembling, but check the position of the thermocouple first. Looks like a small brass rod which sticks into the flame. This is a safety mechanism to prevent the flame being blown out and leaving the gas on. Good luck

Jan 16, 2009 | Heaters

1 Answer

The heater won't stay lit

Hi Tiffany,

When a gas applaince goes off it is usually because of a safety precaution. When the unit dies not detect a flame, it will shut off so that it does not fill with gas and cause damage. A flame sensor is a metal toothpick type item that is in the flame area and could be dirty, although it is two months old, this may be another problem.

But if it is charred, you will need to clean it using a soft cloth or even a well used dollar bill. Don't use abrasives, it will take the coating off of the part and cause it to wear faster.

If you are unsure, below is a link to the manufacturers website, you can get the technical information there.

Click here for Heater Manual


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Vs24pr propane heater

i would change thermalcouple which keeps flame lite

Dec 13, 2008 | Heaters

2 Answers

Heater not staying lit

my furnace pilot light is on but the burners will go off when we put the thermostat on auto. if we keep the fan on the burners will light but turn off the fan and and the burners go off

Mar 01, 2008 | Goodman GMS90703BXA Heater

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