I got a difference of 1,800 between debits and credits on the trial balance. What type of error is this

It could be a lot of things. You could have an account with a wrong debit or credit balance like cash having a credit balance when in fact cash has a normal debit balance. You could have posted your debits an credits to a wrong account. You could have transposed a number when you transferred your accounts from your T accounts to the trial balance. These are the most common errors.

Post what you have done and I can look it over and try to find out where the error is.

You can upload an Excel file by clicking on the Go Advanced button below where you go to post an answer. Next click on the Manage Attachments in the Additional Options section. This will bring up another window. Now browse through your files and double click on the file you want to upload. Now the file path should appear in the white box next to the browse button. Now click on the upload button and your file should be attached to your answer. Now submit your answer and you should see your file in blue as an attachment to your answer.