Mosquito Magnet Forum

I have a 4 year old Liberty (corded) that has more or less worked pretty well until last year. I have had problems keeping it running. I am an engineer, have seen a lot of MM "how to" sites, and have gotten real good at taking this thing all apart. I understand the major components.

Symptom is that it won't light up. Goes to "Insuff. Gas flow" condition after 10 mins or so. Body never gets warm.

I have cleaned the nozzle. I can take the carburetor out of the cast body, and either jumper the valve on with a DC voltage, or cycle the unit for startup, wait until the ignitor /valve comes on and hold lighter to the nozzle. I get a good, symetrical "lighter" type of flame. Conclusion: Gas supply, valve and nozzle is good.

The ignitor heats up and glows a bright orange yellow when power is applied. I have removed it from the body while the unit is trying to start up (flashing yellow) and it is glowing. Conclusion: ignitor is good

The thermistor ohms at about 220K cold. I held it in a lighter flame and got it to drop all the way down to the single digits. I can "fool" the circuit if when it is trying to start up I remove it, and hold it in a lighter flame. The yellow LED goes solid. Conclusion: thermistor is good.

I took apart the heater/catalyst body tonight. There was and ANTS NEST in the intake side of the catalyst cylinder!!! Probably 50-70 of them and a bunch of larvae. Medium sized black ones, they were too big to go through the honeycomb inside, only inside the front via the intake screen. Judicious use of the shop vac and compressed air and I got them all out. I could see through the cylinder and it was pretty clean inside. No ants, no larvae. I thought I had nailed it......

Figured that was it, but put it back together and started it up and could not get it to light up at all. Had the top cover off so I kind of blocked the fan a bit with some rags to simulate closed cover, but still nothing. Then disaster struck, the clip leads I was using on the circuit board moved, shorted something, and a black rectangular device lost all of its smoke.

But lets pretend that last part didn't happen.

Ideas what is wrong? The inside body it pretty clean, although if I take it apart again, I will glass bead it. Only thing I didn't check is the drain hole. Baffles me that the gas lights up outside the body, but not inside.

Questions:

Is there a way to bypass the 3 minute fan run before the gas valve and heater starts? Its a pain in the ass waiting.

The two air passages adjacent the carburetor/nozzle we blocked a little with ant garbage, but were clean in last trials. Are there other airflow areas to look at?

How long does the catalyst last? Can you buy replacements?

How about the circuit board? Anyone swap/sell good used parts? I will try to see if I can just replace the cooked component. It seemed to function fine before that smoke incident.

Is the cover that critical? I was about to try it with the cover on....

Can you start it up without the fan running? Mine (Liberty, corded) faults to a fan error code if I unplug the fan. I assume in that state it will not actuate the ignitor and gas valve.

Any other ideas!!??

I killed a ton of mosquitos with this thing each summer when it worked, would love to get it back on line again ASAP!!!

TIA

John H

All right, I reply to my own post since I did fix my Liberty. Turns out that while the flame from the nozzle was there, it was partially clogged. I cleaned it with solvent again, blew it all out with compressed air, and the flame was bigger, close to 2", from 1" .

Got the smoked PC board component from mouser.com (full wave bridge rectifier chip), replaced it and it fired right up first try.

Lesson learned, don't assume that your gas flow is good just because you see a "lighter" type flame. I am convinced that I will probably just clean the nozzle every spring from this point on.

Hey, John. I wonder if you can help me work out what's wrong with my Liberty. It ran good for three seasons and this year it began to stop and eventually showed a red fault light. Where do you get this 'Code' from? Took it apart and assumed it was the igniter, so replaced that with a 12v igniter. Took it to pieces and cleaned out all the crap that had built up inside due to oxidization (there was lots of it). Cleaned out the drainage hole, reassembled using silicone sealant around the gas nozzle compartment as per the original seal area. Put it back to together (less top on) and tried it again. It got hot after about ten minutes, amber light stayed solid for about ten more minutes and then it went to faulty again. Could it be the thermisister? Or is it the nozzle? I'm at a dead end. Any help would help. Thanks in anticipation. Merv