Difference between conventional oven with fan assisted and convection with fan assisted?

They're the same thing - convection ovens are also known as fan-assist ovens (see for example wikipedia), since they're basically an oven with a fan. Maybe what you had previously was marketed as a fan-assisted oven, and threw out the phrase "conventional cooking" to emphasize that you can still do everything you conventionally could. But it sounds like you're just talking about two different convection ovens here.

More likely, the problems you're having are to do with either the convection being more efficient in your new oven, or the temperature control being off on one of the two. Ovens aren't always perfect, so likely your new oven is hotter when you set it to a given temperature than the old one. It might also have a more efficient fan. You can probably learn to adjust by trial and error - reduce temperatures, and check things frequently until you figure out you've gotten it right. It might also be helpful to grab a thermometer and see if your new oven is lying to you about the temperature.

(If you were previously using non-convection recipes in a convection oven, without adjustment, then your old oven was probably either too cool or its fan wasn't doing much. If you were adjusting recipes for convection previously, then maybe your new oven is hotter than it should be.)

They are definitely not the same thing. Fan-assisted conventional cooking blows air through the oven cavity, but the heat comes from the heating elements at the top and bottom of the inside of the cavity. Convection cooking circulates the air from the cavity over a separate heating element that is not inside of the cavity. This is an important distinction - Convection cooking results in dramatically lower cook times, while fan-assisted cooking reduces cook times, but not by as much.

Be careful with your terms:

• Conventional/traditional cooking is using the top and/or bottom heating elements with no fan circulation.
• Convection cooking is using a separate heating element with a circulating fan.
• Fan-assisted cooking is using the top and/or bottom heating elements with fan circulation inside of the cavity.

I own a business that services industrial ovens and Furnaces. and have been doing this for 0ver 30 years Your basic "home"oven is a true convection oven as was pointed above. The fan assisted oven (AKA mechanical convection oven) has airflow that increases the temperature accuracy up to 5-10 degrees in some instances as well as supplying greater uniformity of temperature throughout the oven interior The coolest places in an oven is at the 4 corners and air flow is a must to prevent this How important this is for cooking a pie I have no clue

Just a thought for you

Convection is using the temperature differential (differences) inside the oven cavity to circulate the hot air inside the oven. Heat rises, cool air sinks but the oven walls itself conducts heat away but the temperature will not be so even throughout the oven cavity. A fan assisted oven has a small fan to move the air around so the hot air is circulated quite well. But the shape and mass of the food as well as oven cavity design will affect how the air flows inside. The heating elements are in the same location as a convention oven. The bigger the fan the better. You food will be more crispy. A forced fan oven has the heating element(s) behind the fan so that the fan directs the heated air directly onto the food like a hot wind blowing on your face (but much hotter and with greater force. This is what an air fryer does essentially. I use one for roasting foods but not for baking. I use a fan assisted oven for baking and the fan is at the rear. The forced fan cooker has the fan and heating element at the top. It works great for what it was intended for and more akin to an active broiler but the heat is circulated with force all around the food as the food sits on a rack. Depending on your fan, and oven insulation, cooking times can be faster by 10-20%. The fan forced air circulating will accelerate evaporation so things get crisper faster. And yes you can put in a water bath.

There's a difference between a convection (traditional) oven with fan assist mode and a convector oven. In a convection oven there're heating elements inside the oven's cavity that passively heat the air, relying on natural convection to spread the heat all around. Since most of the heat will rise to the cavity's top and stay there, a fan assist option is offered to uniformely spread this heat around.

In a convector oven the heating elements are hidden and the fan is the principal heat source. You can tell that your oven is a convector because there are no heating elementes inside the cavity. If you turn the convector fan off, the oven cooking action will change from forced convection to natural convection, but it won't be the same because the heating elements are not inside the oven's cavity (negating most of the heating element's IR radiation).

I have a convection oven and it does not have a fan in it. Now i can't buy a oven with out it being a fan forced. There is a difference between the two. Plus when you see recipes they give both temperatures usually 20 degrees difference. So they are not the same.