Originally Posted By: rcallis
This post was automatically imported from our archived forum.
There are a lot of vent/free heaters on the market these days Empire, Vanguard, Comfortglow, Rinnai and many more. These unvented heaters have been allowed and disallowed both in the codes for years. As of now they are not allowed in bathrooms or bedrooms. But they have been in the past. A few years ago they weren’t allowed in mobile homes, now they are.
Any unvented heater or unvented gas log installed now MUST have an ODS (Oxygen Depletion Sensor) on it. An ODS will only allow the appliance to use approx 2% of the available 20% of oxygen in the air.
Many localities still do not allow unvented appliances but most gas codes say they're O.K.
To answer the original question, a gas appliance without a 100% safety (pilot light, thermocouple, gas valve) would be grandfathered only to the original owner in my area. BUT, if the gas is ever turned off or a new owner moves in, then the appliance could and should be Red Tagged and taken out of use.
Sorry for the run on, but I've been in the propane business for 25 yrs and I couldn't help myself.