Heat Pumps and Electric Heating - air handler blues

I have noticed that intermittantly, the air handler skips an "on" cycle, when the outside unit kicks on. My fix for this has been to set the tstat control from "cool" to "off" and then to "heat" then back to "off".I turned the fan switch from "auto" to "on", to see if the fan would come on and it does. wait a few minutes and turn it back to "cool", after a short delay it comes on. Fan motor is good, thermostat control is good, capacitor is good. I don't have a system drawing to see what parts wire in the line:wall:

Check blower relay or the blower control board. Sounds like you can have a time delay on that blower control board . The G wire should go to it in the blower unit.
Can jump R to G at tstat should get fan if you dont after a short time can be fan control in the tstat .

I installed a new thermostat control when it started this but didn't fix it. Where would the blower relay or the blower control board. be at ? :confused: The fan work fine if you go"cool" to "off" and then to "heat" then back to "off " then "cool":rolleyes: .

If you jump R to G at the tstat does the blower come on??

I would have to agree. If jumpering r to g doesn't turn on the blower, you would have a bad board or relay. Sometimes these can fail intermittently.

Yes blower come on. were is blower relay or the blower control board at?

HELO IS ANYONE HOME:confused:

We are not on line all the time.

Now if the blower runs fine when you jump R to G at the stat. Then it sounds like its in the tstat .

It quit working today jumped r to g and no blower:(

Does it get power ????? When calling for fan if you push it will it run???? If so you need a new capacitor for it

Its Not Getting Power To At Blower

That pretty much nails it down. Your relay is bad. On newer units the relay is on a circuit board. In this case, you replace the board. Its easy to find, the motor wires connect to it.

It's not unusual to have a relay fail intermittently. This can be a little frustrating. It may work perfectly 100 times in a row, then when no one is watching, it doesn't work.

:confused: COULD MY DEFROST COTROL CIRCUIT BOARD IN MY OUTDOOR UNIT HAVE SOMETHING TO DO WITH THIS:confused: I THINK THAT IT MAY NOT BE DEFROSTING RIGHT? IF NOT I LOOK IN THE AIR HANDLER NO CIRCUIT BOARD RELAY IN THERE. I SEE WHAT LOOKS LIKE TO FAN COIL SEQUENCER BLOWER CONTROL TIME DELAY RELAY ONE HAS WIRE LEADS FROM FAN GOING TO IT. THE OTHER LOOKS LIKE IT GOES TO HEAT STRIPS. WHAT DO YOU THINK:rolleyes:

bump just to put me at top

:confused: COULD MY DEFROST COTROL CIRCUIT BOARD IN MY OUTDOOR UNIT HAVE SOMETHING TO DO WITH THIS:confused: I THINK THAT IT MAY NOT BE DEFROSTING RIGHT? IF NOT I LOOK IN THE AIR HANDLER NO CIRCUIT BOARD RELAY IN THERE. I SEE WHAT LOOKS LIKE TO FAN COIL SEQUENCER BLOWER CONTROL TIME DELAY RELAY ONE HAS WIRE LEADS FROM FAN GOING TO IT. THE OTHER LOOKS LIKE IT GOES TO HEAT STRIPS. WHAT DO YOU THINK:rolleyes:


there still has to be a relay to run the indoor fan on a call for cooling, it's probably wired in parallel to the sequuncer trace the wires back from the fan motor to find it the problem as you describe it would involve the defrost board.

the interior fan cut out on heat or cool

COULD MY DEFROST COTROL CIRCUIT BOARD IN MY OUTDOOR UNIT HAVE SOMETHING TO DO WITH THIS I THINK THAT IT MAY NOT BE DEFROSTING RIGHT? IF NOT I LOOK IN THE AIR HANDLER NO CIRCUIT BOARD RELAY IN THERE. I SEE WHAT LOOKS LIKE TO FAN COIL SEQUENCER BLOWER CONTROL TIME DELAY RELAY ONE HAS WIRE LEADS FROM FAN GOING TO IT. THE OTHER LOOKS LIKE IT GOES TO HEAT STRIPS. WHAT DO YOU THINK

the interior fan cut out on heat or cool

COULD MY DEFROST COTROL CIRCUIT BOARD IN MY OUTDOOR UNIT HAVE SOMETHING TO DO WITH THIS I THINK THAT IT MAY NOT BE DEFROSTING RIGHT? IF NOT I LOOK IN THE AIR HANDLER NO CIRCUIT BOARD RELAY IN THERE. I SEE WHAT LOOKS LIKE TO FAN COIL SEQUENCER BLOWER CONTROL TIME DELAY RELAY ONE HAS WIRE LEADS FROM FAN GOING TO IT. THE OTHER LOOKS LIKE IT GOES TO HEAT STRIPS. WHAT DO YOU THINK

the interior fan cut out on heat or cool

looks like I'm out of luck here!

OK I Have replaced both DELAY RELAY inside air handler and capacitor on motor also thermostat:wall: it work fine after replacement of parts for 5 days and its right back to the air handler skips an "on" cycle, when the outside unit kicks on the blower don't about every other day or so:wall: .

Hmmmmm. On some units, the defrost board may control the indoor blower at certain times. Such systems use a low pressure switch to initiate the defrost cycle rather than a timer.

This type of setup can be a little tricky to diagnose.

l'm open to anything that my help me to get it working before it gets cold!:confused: The unit is 10 year old GMC

l'm open to anything that my help me to get it working before it gets cold!:confused: The unit is 10 year old GMC


just because the delay relay is new don't assume it's a good one.

I'd have to agree. It looks like we are back to the blower time delay relay or its associated wiring.

Was any work done to the unit at a previous time? Perhaps it was miswired.

No previous work, a capacitor was replaced two years ago ,it just started doing this last year off and on

Every time I have had the symptoms you describe it has been the blower relay. I usually just replace with a standard relay and not the time delay as they don't seem to last as long.

I've done that a few times too. Those Goodman time delay relays can have a short life and often fail intermittently. I have seen them go bad in less than 2 years.

Perhaps the wrong relay was replaced. The blower td relay looks like an electric heat stack relay with 5 connections. 2 for the 24 coil and 3 others labeled 1,2 and 3.

Post some pics if possible.

I have changed that blower td relay , But will try to get some pictures in the AM