Fixing items during Chol Hamoed:
The general rule: In general, it is forbidden to fix items in a professional way during Chol Hamoed. This applies even if it is needed for the sake of the Moed. However, it is permitted to perform amateur fixing jobs on Chol Hamoed if it is being done for the sake of the Moed.
Professional fixing jobs are forbidden to be done even for the sake of the Moed, unless it needs to be done for the sake of preventing a monetary loss. Likewise, it may be fixed even professionally if lack of doing so poses a danger. Likewise, it may be fixed even in a professional way if it is needed for the sake of making food during the Moed.
Examples:
- One may knock a nail into a wall on Chol Hamoed for the sake of hanging a picture, if one will benefit from the hung picture on Chol Hamoed. The same applies to any screw or nail, that it may be banged, or screwed in, if the item is needed to be used during the Moed.
- One may attach a Mezuzah onto a door on Chol Hamoed.
- Electrical appliances that are needed to make food [i.e. an oven or mixer] may be fixed even in a professional way for the sake of making food during the Moed.
- Fan, heater, air conditioner: May be fixed even in a professional way if the heat or cold is causing one pain.
