I have a dayton garage heater. The model # on the valve is v800 A 1055, Regulator V5306 A. The pilot flame goes out soon as I let go of the button. I replaced the themocoupler, And still have the same problem. Now what is the V800 bad... Thanks Joe cold in Ohio

Are you making sure that the bulb on the end of thermocouple is in the flame of pilot while holding pilot button down and that you are holding down button long enough before letting it pop back up
Let us know

Yes I did... jatlas

Yes I had it red hot