ambient temperature?

Dear All....
As in recent project our company ask us to do a stress analysis of a pump station.But client could not confirm when it will be installed. Should i use the lowest ambient temperature of that area as ambient temperature.And if the project is constructed at different ambient temperature,what is the appropriate ambient temperature? the lowest ambient temperature? is it conservative?
By the way, i modeling the pump nozzle as ANC then the load at both nozzles(suction and discharge)is higher than the allowable load which was pplied by vendor.What should i do? is it appropriate to set gap at restrains of nozzls node, or modify my layout.
thanks~

Dear Srabbit,

Use lowest ambient temperature although the pump nozzle loads fail. Also try higher ambient temp. If pump loads fail again then you must change piping layout or add more flexibility. It's better to see output plot of operating load case and find the contribution of each forces and moments. It helps you to fix and eliminate pump failure.