Honeywell chart recorder question

I am using a Honeywell DR4500A chart recorder and want to configure it to record BTUs on a chilled water loop. I have a supply temp, return temp, and flow. All inputs read and record properly, but when I go into 'input algorithm' and select A-B*C (A = return temp, B = supply temp, and C = flow) input 1 displays what appears to be BTUs. What throws me off here is that input 1 was reading return temp before. If reading input BTUs on input 1 is the expected behavior, how can I see the return temp reading?
Thanks

Input 1 is still the return temperature* but Pen 1 is no longer displaying Input 1* Pen 1 is now displaying the results of the Input algorithm

In Honeywell terminology* the result of the INP ALG is PV 1* a Pen Value* in this case Pen Value 1.

The Upper display shows other Pen Values* where each available pen is assigned a function.

By default:
Pen 1 = Input 1
Pen 2 = Input 2
Pen 3 = Input 3
Pen 4 = Input 4

Enabling INP ALG results in a calculation which uses PV 1 (pen value 1)* displayed in the Upper display* replacing the former PV1 = Input 1. Now Pen 1 = BTU when INP ALG is enabled.

The Lower Disp button cycles through a long list of items whose values are displayed in the lower display. Each input is identified with 3 characters: IN1* IN2* IN3* IN4 and its value.

So* it appears that the BTU calc is now in the upper display* but you should be able to find each of the input values by using the Lower Disp button to view the values in turn.

For some reason the comma character is not functional* replaced by the asterisk (the star *)