Any Trick to it?

OK, I feel embarrassed to even ask because I think I know what to do but it isn't working. How do I get my 1+ yr old setter to go through the swinging door into his Dog Den house? Sounds easy right? Here is the history. Got him home this summer and put him in his run with a pointer next to him. Once it started getting cold the pointer would go in and out and after a few days the setter did as well. The setter went away to the trainer for over a month and now is home. While he was gone I sold the pointer, so the setter is now outside alone, in his own run. It has been very cold and I have the heater on and fresh bedding in the Dog Den. He will not go in on his own. I can put him in there but he comes right back out and lays on the raised bed outside. Here is the kicker...if I prop the door open and leave it open, he goes in and out on his own. No problem but it is wasting the heater and not keeping it warm for him on the really cold days. When it gets really cold I want him to be OK out there, but he won't unless he goes inside to warm up. Thoughts?

Try replacing the door with the overlapping heavy plastic strips like the ones used on overhead doors. He may just want to see what he's getting into before he goes thru the door. Move the raised bed inside, or just move any blankets and/or bedding from the raised bed inside.

try getting rid of the rasied bed

When our labs were outside, we put a large piece of rubber on the door of the door of the dog house. It was kind of a swinging door. Each time we put it up, the dogs would tear it down. We figured it was either they were to hot or they just wanted to see what was outside.

No they were side by side, no sharing involved. only knew each other for 2-3 months

He's PO'd because you sold off his best friend! Might just be one of those things he will have to learn (again) the hard way. Did they share the run/den when you still had the pointer?

I have tried treats (he is actually not a big fan of them), I have tried putting him in there with the top open..in/out...in/out...repeat, I have put his food in there - he eats and comes right back out. After this little stint of cool weather I am going to try to turn the heater off (maybe it is too hot in there), close the swinging door and let him be. If he gets cold he will have to go in or freeze. Like kids...sometimes they have to go thru hardships to learn on their own - or I just dog a box of rocks dog that is a rock star in the field.

sounds like something hot dog pieces or liver sausage could fix real quick