Dometic Refrigerator cooling

Garry&Gayle wrote:
I have a Dometic RM1350 Refer; when turning on the unit works great whether gas or elec. on setting 4 refer runs about 35 deg. freezer is 0 deg. then around 4 pm it warms to around 40 deg. then by 3 am its back to 35 deg. again. After about a 7 to 14 days at 4 pm it warms to 45 - 50 deg. but then only cools to maybe 40 deg. regardless of exterior temp. this is not the 1st time it's done this, any ideas? Cooling fans are running, changing temp setting makes no difference, refer side is facing East, so no afternoon sun

I get the feeling it goes into defrost mode and doesn't come out of it completely.

Your Model Dometic has no defrost mode. But, if your sig is correct, the unit is about 7 to 8 years old. You may have a partially blocked cooling unit. Your symptoms show that. When hotter temps exist, the CU cannot do a good job. When the sun goes down the CU catches up. But, the 1350 does not have a good history of good cooling even when new. Doug