Water Heater Exhaust is making our house smell!

Our water heater is creating a smell in our house that stinks! We notice it when the water heater is running and after. We have called our local plumber and the gas company and no one is able to identify what is wrong.

The water heater is 9 years old and is a power vent. We can't figure out the reason why it could be smelly.

Any advice would be great! Thank you!

The fan motor could be going out. What does it smell like? Does the fan actually run?

It smells kindof like a gas smell/stale smell. The fan does run and we can usually smell it in the morning and in late afternoon. We have had two plumbers and our gas company check and they say everything is fine and running good.
I think your advice is probaly right. I have noticed a lot of the same posting with that outcome.
Would you suggest waiting until it goes out or replacing it right away? When we replace it should we get a brand new one or replace the fan?
Thank you in advance for your reply. I really appreciate it! As you can tell we have been dealing with this for a little while now!

If you don't own one, go out and get a CO detector. While CO is colorless and odorless, smelling combustion by-products may mean you are poisoning your family slowly. Symptoms are headache, a ruddy complexion (CO bonds to blood better than O2 or CO2 and makes blood look like it is fully oxygenated and thus brighter red than normal - this shows through in the skin for Caucasians), drowsy, or lethargic.

If the fan is not doing its job or the vent lines are plugged or have holes, or are not installed properly, you could be getting combustion products in the house.

If there is an intake near the exhaust, that could be a problem as well.

A correctly working combustion device has very little CO, or unburned combustion products.

We have a CO2 detecter and it doesn't show anything. One of the plumbers also did readings around the house and nothing showed. Thank you for thinking of the safety of my family.

I'll have my husband look for some of the things you mentioned.

Thanks!