Furnace won't ignite 2005 Hornet

[4everyoung]

Hello: Our heat had been working but after a month of non use it appears only the fan runs. We can hear the igniter click but it won't light and we smell gas. It is located under the couch and doesn't seem to have any way to get inside. Any ideas? Do we have to replace entire unit? Thanks.

[RichR]

If you can hear the ignition and smell gas look to see if you have low voltage from the battery or you may have insufficient gas pressure. I just had a similar problem and found out the pressure regulator at the tanks was going bad. Why that happened I surmised was that oil from the tanks was getting to the regulator diaphragm and deteriorating it. I replaced the regulator and the furnace is working fine.

[chuckster57]

Are you in an area that has wasps? If so do you have screens on the furnace plate on the exterior? If not, wasps and mud dawbers lovec to get all the way into the furnace and make a nest.

Low voltage won't spin the fan fast enough to set the "sail switch" and that won't allow the gas valve to open.