Heat n Glo FB-IN Pilot lights, main burner won't light

[806stove]

I appreciate any help that can be offered. Here are the details:

• Moved into new home (built in 1920's) with masonry fireplace that had a Heat N Glo Model FB-IN gas insert on Natural Gas installed.
  
• Insert is set up to work with a remote, but they didn't leave the remote for us when last people moved. I haven't purchased a new remote yet.
  
• Insert plugs in to a receptacle but not to a switched receptacle.
  
• There is a toggle switch on the model that is hidden behind the surround / fascia, which was disconnected when I first looked at the stove. I reconnected it to the proper wires.
  
• I thoroughly took apart the insert and cleaned everything, but did not take any gas components apart.
• Checked all electric connections; all are solid.
• Has a Continuous Pilot, which DOES light up easily and stay lit.
• I have tried every switch variation / combination but cannot get the main burner to light.
• The main gas adjust knob doesn't seem to affect flow of gas (I suspect my problem lies herein)
• The main burner will sometimes put up a small blue flame, but it instantly goes out.
  
• I know there is at least a small flow of gas coming through the main orifice, as i can light it directly, but there doesn't seem to be any pressure behind the gas. Main flame looks like a large candle flame; goes straight up.

Thanks in advance for any advice you may have. I am new to the gas insert world. Otherwise, please direct me to another thread if i missed one.

Thanks!

 

[DAKSY]

First of all is the On Pilot Off switch in the ON position? Nothing will turn the unit on unless it is.
Have you taken a millivolt reading on the thermopile? Put your multimeter probes on the TP & TP-TH (or TH-TP) teminals. & take a reading. You should be getting between 500 & 600 mV DC. When you close the switch to turn the unit on, that number should drop to about 200mV.
Did you try jumping the connections on the terminal block? With a small jumper wire or a paper clip, jump the terminals labeled TH & TH-TP (or TP-TH). That should open the gas flow to the burner. You will hear a "CLICK" when the gas flows.
Report back with your findings & we will take it to the next step, based on what you tell us....

 

[806stove]

Bob -

Thanks for your quick response and the help. I will take a look tonight and report back with my findings.

Ian

 

[806stove]

Ok. Pilot is on. Pilot flame looks good. Power is coming through to the junction box with receptacles (under unit with two receptacles for remote and blower). ~ 500 mV when main switch is off on the thermpile and drops to about 200 mV when I turn on the switch. Tried jumping the terminals on the junction box but get no click and no gas.

Next step?

 

[806stove]

(To be more precise, actually about 460-470 mV when switch is off when testing thermopile)

 

[806stove]

Hey! I solved the problem. Something was plugging the main orifice. I read on another forum that a certain spider likes the smell of the NG additive. I cleaned out the orifice with a paper clip and was in business. Thanks for all the help.

 

[DAKSY]

Hey! I solved the problem. Something was plugging the main orifice. I read on another forum that a certain spider likes the smell of the NG additive. I cleaned out the orifice with a paper clip and was in business. Thanks for all the help.

Believe me when I would have sent you there next. Those damned spiders will create havoc...