When the weather turns cold and we switch from the cooler to the furnace...

[Drako]

Has the OP succumbed to CO poisoning?

 

[Iron Woode]

It's not an animal obesity issue, it's a dominance and control issue. If you give your animal food they know that you are in control of the food and are in control of them. This is especially true of dogs.

Now, for humans, it's the same. People are given food stamps so they always know who is ultimately in control.

that's what cats want you to believe.

unlike dogs, where you are in charge, cats are the ones in charge.

You are the cat's bitch.

 

[IronWing]

OP, do you have CO alarm?

Yep. No CO problems. Ducts cleaned about five years ago. Furnace filters changed regularly.

anyway why do you use the AC until you have to heat, that sounds weird.

Desert climate. Daytime highs in the nineties one day and nighttime lows in the 30s the next night. The swamp cooler and furnace share ductwork with slide in panels opening up one and closing out the other. With a swamp cooler one leaves as many windows open as possible as swamp cooling is a flow-through system with a constant supply of outside air. This time of year we were only running the cooler a hour or two a day but had all the windows open. With the arrival of a Pacific cold front temps dropped to where we needed the furnace so all the windows get closed up to keep the heat in. This transition is what gets the cats. Once they adjust to the loss of constant fresh air they stop with the puking.

 

[Iron Woode]

cats puke for a variety of reasons.

the most common are:
illness
hairball
stress

its possible the furnace sound caused the cats stress and puke.

My cat didn't like the central air sound in the house during summer. She didn't mind the furnace in the winter.

 

[Nintendesert]

that's what cats want you to believe.

unlike dogs, where you are in charge, cats are the ones in charge.

You are the cat's bitch.

That's why I only have dogs. I can't deal with cats and their toxoplasma!