RULES

1. If (excvalv is open) and (pressat is open) then (statvalv is open)

2. If (excvalv is a room) and (pressat is a room) then (statvalv is a room)

3. If (excvalv is in the middle) and (pressat is in the middle) then (statvalv is in the middle)

4. If (excvalv is three quarters) and (pressat is three quarters) then (statvalv is three rooms)

5. If (excvalv is closed) and (pressat is closed) then (statvalv is closed)

6. If (excvalv is open) and (pressat is strongly closed) then (statvalv is stuck open)

7. If (excvalv is open) and (pressat is three quarters) then (statvalv is set)

8. If (excvalv is open) and (pressat is a room) then (statvalv is difficult to close)

9. If (excvalv is a room) and (pressat is in the middle) then (statvalv is difficult to close)

10. If (excvalv is a room) and (pressat is three quarters) then (statvalv is necessary)

11. If (excvalv is in the middle) and (pressat is three quarters) then (statvalv is difficult to close)

12. If (excvalv is in the middle) and (pressat is closed) then (statvalv is in need of maintenance)

13. If (excvalv is three quarters) and (pressat is closed) then (statvalv is needed)

14. If (excvalv is closed) and (pressat is strongly closed) then (statvalv is fort)

15. If (excvalv is closed) and (pressat is open) then (statvalv is stuck closed)