Plumber26

If the pipes connecting to the nipples are copper, then what you are seeing is an example of electrolysis. When two dissimilar metals are touching they corrode on another. They make dielectric unions and dielectric flex connectors to prevent this. (code in my area) You can even attach a brass threaded coupling to the galvanized nipple, then screww a copper male adapter into the coupling and that will work as well. If this is at your house, I'd replace it before it gets too bad b/c if you wait untill it leaks, you'll not likely get the nipple out and have to replace your tank.

Do not like when washers use an overhead drain. Not only is it a mess when sewer line backs up, it's gotta be hard putting more head pressure on the washer's pump. But that aside, at least put a check valve in the drain line.

The tiny leaks that can't be found with bubbles might not even be leaks. You are aware of all of the things that your sniffer will react to, right? If there're aren't bubbles, I have a hard time believing that the gas leak (if it actually is one) is worth fixing. It certainly doesn't pose a hazard and the amount of money that's wasted is really, really, tiny. - Jim Katen, Oregon Yes, I am aware and have indeed gotten "false readings" here and there but I do not solely rely on the sniffer to detect a leak. I do verify leak with bubbles. Perfect example: I went out to a customer's house for an "issue" with gas water heater. Arrived at the call to find the knob on the gas valve melted. During my questioning of the customer, realized that the husband (we'll call him Mr. Fix-it) had went to the local hardware store and bought a new thermocouple b/c of a constant pilot outage. this was one full month before this "issue". I was able to get the pilot relit only to find that the pilot tube connection to gas valve was barely tighter than hand tight. This was a small leak but a leak none the less. His response, "I thought I smelled a little gas but I thought it was just when it first fired up. Luckily they were home when this occured or they would have came back to a stack of charred wood. Just sayin'.

I have a Ridgid Gas Sniffer and I have to disagree with the "there's no need to use it" idea. Since purchased about 1 1/2 years ago I have located at least 30-40 gas leaks at different customers' homes and some houses have found multiple leaks. Even found very tiny leaks that were hard to find even with bubbles. Leaks on the gas meter that were on the gas company's side, leaks on propane tanks from improperly installed tank connections. A gas leak, aside from being a potential danger, also cost money. Don't always rely on your nose to smell it.

If you see a gas water heater on the floor, look in the installation instructions for that heater and somewhere (most times on the cover page) there will be some language to the affect of .."conforms to ANSI Z21.10.1" This is the standard that deals with the FVIR rating. If it's there, it's good. In my area, electric water heaters are required to be on stands because the lower element/ t-stat are considered to be an "ignition source".... go figure.

Another thing to note is to me that looks like 1/2'' gas piping entering the unit. I would recommend having installation instructions checked b/c gas piping may be undersized. Most Rinnai gas conections are 3/4'' but that does look like an older model.

When the Rinnai is operating the blower does vary in speed depending on water flow, inlet water temperature, and amount of gas being used. Its is a very efficient unit in that it will use any where from 15k - 199k BTU's. Basically, it only uses the amount of gas needed to heat the amount of water traveling through it from the inlet temperature to the set temperature on the thermostat. Now the noises coming from the unit if it were not in use is very strange and should not happen unless somewhere in the water system their is a pump. Did you notice whether or not they had a hydronic air handler that may have been connected to this unit? Rinnai does make air handling equiptment and the tankless water heater can be used w/ existing hydronic air handling equiptment of a different brand. (tankless version of Apollo, Polaris, or Lennox CompleteHeat set-up)

In that situation I would use either a compression gasket (rubber gasket that acts as the "caulked joint") or if it's horizontal, I would rather cut the cast iron and use a no hub adapter and no hub band.