4 Signs Your Water Heater Was Installed Wrong

The only time you really think about your water heater is when you don't have any hot water. That's not a knock on anybody. Nobody is hanging out thinking about their water heater. I can't count how many times a customer has told me they just put theirs in a couple years ago, and then I look at the manufacture date and it's nine years old.

If you don't know how old it is, you probably don't know who installed it or how well. So whenever I walk into a house and see a water heater, I look at a few things that tell me whether the installer knew what he was doing, whether it was a novice, or whether the homeowner did it themselves. Here are the four I check first.

1. The venting

This is the first thing I look at. I can't count how many times I've walked into a house and seen a dryer vent used for the venting on a tank water heater.

This goes for tankless too, and on a tankless the venting is even more important. A tankless is forced air, not atmospheric. If it has the wrong venting and it isn't airtight, it can push carbon monoxide out into the area you're living in, and that can kill you. If you're weighing the two types, we break down the differences in tankless vs. tank water heaters.

What to look at: if the vent on your water heater looks like a dryer vent, that's a problem. If you think your venting is wrong, don't keep using the heater. Call a licensed plumber. This is not one to work on yourself.

2. The seismic straps

It's funny, because even on the cleanest installs I've seen the straps done wrong. Sometimes they aren't connected in the middle correctly. Sometimes they're screwed into the wrong areas. I've seen water heaters strapped where the anchor goes straight into the drywall and not the stud, and I've even seen drywall anchors used.

If there's an earthquake and your water heater is screwed into drywall, that drywall screw is no match for your 400-pound water heater.

What to look at: follow the straps to where they meet the wall. If they're screwed into bare drywall, or into drywall anchors instead of a stud, or the two ends aren't joined properly in the middle, it's worth having a plumber look at it.

3. The thermal expansion tank on the wrong side

The thermal expansion tank should always be on the cold side, not the hot side. I find them on the wrong side more often than you'd think.

A lot of people think skipping the expansion tank saves them money because it doesn't cost anything right now. It costs you later. We installed a Moen leak detection device for a customer that reads the water pressure and usage and detects leaks. The very next day he called us back: his pressure was reading 170 PSI, which is extremely high. When we went back out to see why, there was no thermal expansion tank on the water heater at all.

Not having one, or having one installed wrong, doesn't only put stress on the tank. It puts stress on the entire plumbing system inside your house. We go into what high pressure does over time in high water pressure and your pressure regulator.

What to look at: if your heater has an expansion tank, it should be on the cold water line. If it's on the hot side, or there isn't one at all, have a plumber look at it.

4. The sediment trap installed backwards

Another common mistake I see is plumbers putting in sediment traps incorrectly. The trap is there to catch sediment before it gets into the gas control valve. A lot of installers don't put one in at all, and that's a big reason gas control valves go bad.

When it is there, I still see the tee laid so the reservoir is pointing down but the gas line comes straight across. That means the gas doesn't dump into the chamber first. The gas should go down into the chamber so it can catch the sediment, and then go into the gas control valve. Installed backwards, it somewhat defeats the purpose of putting a sediment trap on in the first place.

What to look at: this one is hard for a homeowner to judge, and it's a gas line, so look but don't touch. If you don't see a sediment trap at all, or you're not sure it's set up right, have a plumber check it on the next visit.

If you spot one of these

Don't try to fix it yourself. Venting, gas lines, and straps all need to be done right, and the venting one can hurt someone. If you suspect a venting problem, stop using the water heater and call a licensed plumber.

For the other three, it's worth getting looked at. A lot of plumbers install the heater, get paid, and leave. A proper water heater installation gets the venting, straps, expansion tank, and sediment trap right the first time. Skipping the sediment trap or the expansion tank to save money now significantly reduces the life of the heater in the long run.