I am not sure, but this is what I think... That's because the water is heated to less than 100 deg C (and a thermostat turns off the heating once this temperature is reached). Still, most models have a safety valve in case excess pressure builds up.
In a word, yes, Reliance water heaters have been around for years and they offer a wide variety of models to suit pretty much anyone's needs from small 1 bathroom homes to 5 bath homes. They come in gas and electric, storage or tankless models.
Yes, as water vapor (steam).
No,they are not cost efficient. Bradford water heaters aren't worth the cost because replication parts are very hard to find and they don't come with refund or warranty.
Lasko heaters come with a one year warranty, along with most other heaters on the market.
Canals
Pool heaters come in several different models. Electricial heaters, propane powered heaters and solar powered heaters are the most common.
It should only be steam.
Since steam is water evaporating, water that becomes steam may not be clean. So, when the steam goes thru, some of the dirt may come off along with the steam when the steam becomes water.Creating deposits in the steam vents.
Steam, which can't be seen, not to be confused with the white clouds that come from a boiling kettle that is water vapour or condensed steam. If you look closely at the spout of a boiling kettle you will see that close to the spout it is clear that is steam or water in its gas form.
That question didn't even come close to making any sense.
The gas being evaporated forms the bubbles in boiling water.
No, they don't. Those that need air entry underneath come with short legs fitted.