Is that natural gas I smell?

On Saturday, I went downstairs and smelled natural gas. It was especially strong in the utility room where the water heater is. We called the plumbing people who had been here on Friday, and they told us to call the home warranty people. We did, and they said they'd contact the plumbing people, which they did (I guess a gas leak is considered moderately important). The plumbing people sent the same tech who was here on Friday. He brought his handy natural gas detector (it makes a screechy noise when it detects gas). Sure enough, I heard little screechy noises coming from the utility room. He said the gas valve on the water heater needs to be replaced. Of course, he didn't have one with him. He ordered a valve and we hope to have it installed Monday or Tuesday. Meanwhile, we turn off the water heater except for a couple of times a day when we want hot water for bathing, washing dishes, etc. We asked the plumbing guy if this would be safe to do, and he said yes. We also put a fan in the utility room to move any leaking gas out to a bigger area. Never in all my days have I had this much trouble with a water heater. Do you suppose it will really be fixed with a new gas valve?