Why Is My Water Heater Having Problems Already?
Updated: Oct 5
We originally wrote about this subject in April 2015, when new federal water-heater efficiency standards were about to take effect. Those standards took effect, water heaters became more efficient, tankless systems became more common, and the equipment itself became considerably more sophisticated. Codes and installation requirements have continued to change too.
But one thing we were seeing back then hasn’t changed: a water heater can make hot water and still not be installed correctly. Sometimes the problem that shows up years later isn’t actually the water heater. It’s the installation.
Most homeowners have no reasonable way of knowing the difference. You shouldn’t have to know how a tankless water heater needs to be vented, whether the gas supply is adequate, whether your plumbing system requires expansion control, what type of copper was used, or how a tankless unit needs to be commissioned for your home. That’s why you hire a professional.
Sometimes an incomplete installation does show up in the price. One quote includes everything the job requires while another looks substantially lower because some of that work isn’t included. But price isn’t always the reason. Sometimes the water heater came with the house. Sometimes it was installed by the builder. Sometimes there was an emergency and the homeowner hired whoever could get there. And sometimes a homeowner paid a perfectly reasonable price to a company they believed was qualified and simply didn’t receive the quality of installation they thought they were buying.
A good sales pitch and a good installation aren’t necessarily the same thing. Unfortunately, sometimes you don’t discover the difference until years later.
A Five-Year-Old Tankless That Should Have Lasted Longer
We recently replaced a tankless water heater that was only about five years old. For a tankless system, that’s young. It should have had plenty of useful life left, but there were problems with the original installation. The venting was incorrect, and the unit had not been properly set up for the home.That second part is becoming increasingly important. Installing a modern tankless water heater isn’t just connecting the water, gas and venting and turning it on. The equipment also needs to be properly commissioned and configured for the home and for the way the plumbing system operates. In this case, problems with the installation and setup contributed to the tankless reaching the end of its useful life far earlier than we would normally expect.
The important part of this story isn’t who installed it or what the homeowner paid. It’s that the water heater worked. It made hot water, and there wasn’t necessarily an obvious reason for the homeowner to know something wasn’t right until the problems started showing up.
That’s what makes these installations difficult for homeowners to catch. Something can work without being right. Sometimes it’s not an issue until it’s an issue.
Today’s Water Heaters Require More Than Plumbing
Plumbing has changed quite a bit in the almost 20 years we’ve been installing water heaters. Modern tankless units have controls, diagnostics, recirculation settings and operating parameters that need to be understood and configured correctly. The mechanical side of plumbing still matters, but knowing how to run pipe isn’t enough anymore.
That’s one reason our technicians are Navien trained. The training covers the complete system, including water, gas, venting, condensate, service valves, controls, setup and diagnostics. A plumber can physically install a tankless water heater and still not understand how to properly commission the equipment connected to it. As homes and plumbing equipment get smarter, the plumbers working on them have to keep up.
When homeowners compare tankless water heaters, they naturally look at the unit on the wall: the brand, model, warranty and price. But much of what determines the quality and serviceability of the installation isn’t the white box. It’s what’s above it, below it and, with today’s equipment, inside the settings.
Look at the piping underneath the new heater in the photo. The isolation kit allows the tankless to be properly serviced and descaled. The appropriate lines are insulated. The gas supply, condensate drainage, expansion control and venting all have to be addressed based on the particular home and equipment. When the physical installation is complete, the unit still has to be commissioned correctly.
Those details require additional material, labor and knowledge. They’re also exactly the kinds of things most homeowners wouldn’t know to look for when comparing two installations.
Almost 20 Years Without an Install-Error Callback
CF Plumbing has been installing water heaters for almost 20 years, and in that time we have never had a callback on one of our water-heater installations because we installed the heater incorrectly.
That doesn’t mean we’ve never been back. Parts fail, components wear out, valves eventually need replacement, and San Diego’s hard water can wreak havoc on plumbing equipment. Water heaters require maintenance, and eventually every water heater will need repair or replacement.
But there’s an important difference between a water heater failing after a proper installation and a water heater failing because of the installation. We’ve dealt with the first plenty of times. We haven’t had the second on a water heater we installed.
That’s something we’re proud of, and it’s also why we don’t remove necessary pieces of an installation simply to make our number look more competitive. We know there’s a good chance we’ll be the plumbers servicing that water heater years from now. We’d much rather come back because a part eventually wore out than because something we did during the original installation shortened the life of the equipment.
Sometimes You Don’t Get to Shop Around
Not every water-heater replacement begins with several estimates and plenty of time to compare them. Sometimes a heater fails on a holiday or a weekend, there’s no hot water, and the decision becomes whoever can get there.
We’ve had longtime customers in exactly that situation. In one case, we were closed for the holidays when a loyal customer had a water-heater emergency. She called another plumbing company because she needed hot water and we weren’t available. The replacement heater they installed wasn’t correct for the fuel source at the home, and it took multiple return visits before the installing company identified why the new heater wasn’t working.
We’ve had another customer replace a tankless water heater while we were closed for an extended holiday. By the time we returned, the installing company was still trying to get the new system operating correctly.
Neither homeowner was trying to find the cheapest plumber. They needed hot water. Those situations are a good reminder that the company installing the equipment can matter just as much as the equipment being installed.
What Gets Missed on Water-Heater Installations?
On tankless water heaters, venting is one of the biggest things we look at. The correct material, sizing and configuration matter, as do combustion-air and manufacturer requirements. A heater can turn on and produce hot water even when something isn’t right, which is why an installation problem may not reveal itself immediately.
Condensing tankless systems also produce condensate that needs to be properly managed. The drain needs to follow manufacturer requirements, be properly pitched and be neutralized where required. The gas supply needs to be evaluated as well. A tankless heater can have very different gas requirements from the storage-tank heater it replaces, and simply putting the new heater on the existing gas piping doesn’t mean that piping is adequate.
Isolation and service valves matter because tankless water heaters require maintenance, including periodic descaling. Proper service valves allow the heater to be isolated and flushed without modifying the plumbing later. Expansion control also needs to be considered when the home has a closed plumbing system.
And then there’s the part you can’t see: the setup. Once the physical installation is finished, a modern tankless water heater still needs to be properly commissioned and configured. Today, installing the plumbing and knowing how to set up the equipment are parts of the same job.
Traditional tank water heaters have their own version of these problems. Two of the most common issues we see involve the T&P discharge and thermal expansion. The temperature and pressure relief valve is an important safety device, and the discharge piping connected to it has to be installed correctly so the valve can function as intended.
Expansion tanks are another common issue. Water expands when it’s heated, and when a home has a closed plumbing system because of a pressure-reducing valve, check valve, backflow device or similar component, that expanding water needs somewhere to go. Without proper expansion control, the resulting pressure can put unnecessary stress on the water heater, valves, supply lines and other plumbing components.
The tank may still make hot water. Again, working and being installed correctly aren’t necessarily the same thing.
Even the Copper Can Be Different
Not all copper tubing is the same. Type M copper has a thinner wall than Type L copper, even though the outside diameter can look the same. Most homeowners would never know which one they’re looking at once the installation is complete.
At CF Plumbing, we spec the thicker Type L copper for our water-heater installations. It isn’t about making the job sound more elaborate. It’s about using materials we’re comfortable putting our name on and coming back to service years later.
A fitting can eventually fail. A valve can leak. Equipment wears out. That’s plumbing. What we don’t want is for the original material choice to have been based on removing quality from the installation simply to lower the price.
Why Two Water-Heater Quotes Can Be So Different
Sometimes one company really does have a better price. A lower quote doesn’t automatically mean a bad installation, and a higher quote certainly doesn’t guarantee a good one.
But sometimes two quotes aren’t actually pricing the same job.
One estimate may include expansion control, proper T&P discharge, Type L copper, insulation, gas modifications, isolation valves, condensate management, proper venting, permitting where required and complete equipment setup. Another may include some of those things but not others.
That’s why we think homeowners should look beyond the price of the water heater itself. You don’t need to become a plumber or understand every code requirement. A simple question can tell you a lot: What exactly is included in the installation?
Why Problems Sometimes Show Up When You Sell the House
One of the strangest things about an incorrect water-heater installation is how long it can go unnoticed. The shower gets hot, the dishwasher works and nobody is standing in the garage inspecting the T&P discharge or looking underneath the tankless heater.
Then the house goes on the market.
A home inspector looks at the water heater and suddenly items that have been there for years appear on the inspection report. We regularly receive calls during escrow to correct water-heater installations that have been functioning for years but weren’t installed correctly.
Now the homeowner is making corrections on a deadline, sometimes years after somebody else performed the original work. Doing it correctly at the time of installation is much easier than discovering it during a sale. Proper installation can also become important if an equipment failure eventually leads to a manufacturer warranty claim.
Once again, it wasn’t an issue until it was an issue.
Water-Heater Installation in North County San Diego
CF Plumbing installs and repairs tank and tankless water heaters throughout La Jolla, Del Mar, Solana Beach, Encinitas, Cardiff-by-the-Sea, Carlsbad and Rancho Santa Fe, as well as select areas of San Diego and Orange Counties.
We’ve been installing water heaters for almost 20 years, and we’re often the company servicing those systems years later. That changes the way we look at an installation. We’re thinking about how the heater will operate, how it will be maintained and how we’re going to service it down the road—not simply how quickly we can get it on the wall.
If you’re deciding between a tank or tankless water heater, our Tank vs. Tankless Water Heaters guide goes deeper into the differences. For installation, repair and maintenance, visit our Tank & Tankless Water Heater Services page.
And if your water heater is relatively new but you’re already having problems, don’t automatically assume the heater itself is bad.
Sometimes the problem isn’t the water heater. It’s how the water heater was installed.
Quick answers
Why did my tankless water heater fail after only a few years?
It can be the unit. It can also be the venting, the condensate, the gas supply, or a setup that was never commissioned for the house. A heater can make hot water for years and still be installed wrong.
Are two water heater quotes for the same job?
Not always. One bid may include expansion control, a proper T&P discharge, Type L copper, isolation valves, gas changes, condensate, venting, and commissioning. Another may be the heater on the old connections.
Does a water heater need an expansion tank?
On a closed system, yes. A pressure-reducing valve, check valve, or backflow device can trap the pressure from heated water. The tank may still make hot water without one. That does not mean the install is right.
Water Heater Installation, Repair & Maintenance in North County San Diego
A water heater should do more than make hot water. It should be installed correctly, set up for your home and accessible for service throughout its life.
At CF Plumbing, Inc., we install, repair and maintain tank and tankless water heaters throughout La Jolla, Del Mar, Solana Beach, Encinitas, Cardiff-by-the-Sea, Carlsbad and Rancho Santa Fe, as well as select areas of San Diego and Orange Counties. With almost 20 years of water-heater installation experience and Navien-trained technicians, we look at the complete system—from the piping, gas supply and venting to the controls and equipment setup.
Whether you need water heater repair, tankless water heater maintenance or a complete replacement, visit our Tank & Tankless Water Heater Services page. If you’re comparing options, our Tank vs. Tankless Water Heaters guide explains the differences.
Having problems with a water heater that should still have years left? Contact CF Plumbing to schedule an evaluation. Sometimes the problem isn’t the water heater. It’s how the water heater was installed.
