I put in a new transformer, and just put in a new board. A couple of days ago I went to shut my heater off and there was no led on the controller. There is still no 24vac getting to r & c where the wires from the thermostat connect. and when I close the door the fan comes on, the only way I can shut it off is to unplug it or leave the door off. I'm just perplexed as to why there is no 24v to the stat. On the board I am getting 24vac to the gas...so....

Start by posting brand/model # of the heater. If blower runs continuously and you are lacking control voltage, this is usually caused by an open limit switch of some type.

Start by posting brand/model # of the heater. If blower runs continuously and you are lacking control voltage, this is usually caused by an open limit switch of some type.

it's a carrier model 394jaw036065 I am pretty sure it's a limiting switch and am suspecting it's the vsss (vent safety shutof switch) but I don't know where it's at. I was looking at the schematic and it says it's a manual reset

If both schematic and ladder diagrams are present, colors of wires connected to these devices would be indicated. There's your clue. Vent/draft safeguard switches are usually located closer to the flue, inducer, or draft diverter.

If both schematic and ladder diagrams are present, colors of wires connected to these devices would be indicated. There's your clue. Vent/draft safeguard switches are usually located closer to the flue, inducer, or draft diverter.

man I looked everywhere...unfortunately the schematic shows the breadboard exterior and interior. I followed the line and there is nothing on it...according the the schematic, the vsss is inline on 'R' and looks like has a hook into sec 1....I went out one line and was looking at vsss switches....there is nothing like that on this thing that I can tell.

ya, that was it....I found it....geez...should have read more carefully could have saved myself 140.00....well, at least I have new electronics...should last for another 20 years haha...

thanks man, that was the trigger I need to get my brain working...

Pass it on...;)