Per request, pictures attached of the cryopump bake enclosure installation. The installation took two days and several modifications were made before and after the bake commenced in an effort to create more uniform heat zones within the enclosure because the bottom is not achieving target temp. Modifications include:

• Changed unitrut framing at 10" valve area to make more space for turbo pump assembly, which is pumping during the entire bake process
• Added rockwool insulation in several areas to fill in gappy joints around the 4" thick insulation panels
• Reduced flow rate of recirculating air by adding restrictor plate on 20" return duct diameter in an effort to equalize heat zones within enclosure. Turns out we had a faulty thermocouple which skewed results; retained design flow rate of 2000 cfm to make up for leaks at velcro insulation joints
• Installed 10 kW heater in series to supplement 20 kW control heater which ran at 100% to achieve temperatures above 100C (target temp is 130C)
• Laid 1-2" thick ceramic sheets on top of enclosure to reduce thermal leaks
• Lined "crawl space" below enclosure floor with 2" foam board to retain heat at bottom, with option to plumb in 5 kW space heater
• Activated GN2 regeneration heating system; it ran flawlessly for over a week and then developed some kind of electrical short that we haven't been able to chase down. Flowing hot GN2 through the CP reservoir would help achieve target temperatures and prevent cold spots, but will unlikely be fixed in a timely manner

Improvements for future designs:

• We read out thermocouples in five areas (some air, some metal), but in the future would add more sensors
• The supply air exists into the enclosure directly above the return duct. We could improve heat distribution by supplying hot air from bottom and placing return duct on opposite side of enclosure
• The velcro serves as a good hold for insulation panel installation, but does not ensure that the panels butt up next to each other. Wire tie reinforcement would help bridge gaps where the thin velcro flaps fail to provide thermal barriers
• Install variable speed drive on fan