Coleman Pressure Switch Failure DGAA070BDTA

[fixitsister]

Hi ~
Terrific site, I'm glad you guys are here!

I recently bought a pressure switch for a Coleman DGAA070BDTA. It's the second one I've replaced in my sister's home in as many years. It seems like at the start of every heating season this switch fails. Is there something I should be doing at the end of the heating season to prevent this?

Thanks for your assistance.
Debra

[furnaceman]

While it is possible to get to bad switches in a row, it is a stretch.
Before replacing it again, lets try a few things. Since I'm assuming you dont have a heli/drwyer meter to test the switch. How about first, look @ the tubing on the switch, is it tight and not frayed or have water in it. Since you replaced it before, i assuming u are confortable taking it off, take a needle/pin and insert it through the holes were the tubing goes on, UNDER NO CIRCUMSTANCES BLOW INTO IT, THAT CAN RUIN THE SWITCH. Also poke into the hole on the combustion blower hole( where the hose fits over). Then re-attach and try again.
This is a quick try fix. If this doesn't do the trick, let me know and i'll try and talk u through a more detailed process.

[fixitsister]

Hi ~

Thank you for your input. When it didn't work at first, I did check the tubes, orifices, and took an amp draw on then fan to make sure it was working. It was odd because the switch I just replaced last heating season would work intermittantly. When I replaced the switch this time, it seemed like the tube that goes to the plastic port wasn't real snug, so I wrapped some electrical tape around the port, cut off the excess so that the hole was clear, then put the rubber tubing on. Would that slight "sloppiness" at that connection have been enough to cause the problem? I did save the switch I removed b/c I thought it might still actually be good.

Thanks again for your advice.

[Robert]

Hi,

Remove tube and tape and use the small radiator screw clamps to snug tubing onto port.


Check booster motor air pipe for clear with no blockages.

Remove motor/housing and clean to be sure it is able to turn freely and fully.

be careful to not damage any gaskets when removing/reinstalling.



Thanks,
Robert