Watch our Video and You’ll Learn:

  • How Expansion Tank Works.
  • Complete Guide About Thermal Expansion Tank And Why You Need It.
  • How Beneficial Expansion Tank Is.

Why We Do & Don’t Them

What is an expansion tank? Many customers ask what they are and if they need them. An expansion tank may be beneficial for some customers, whereas they are not necessary for others. 

Watch our Video and You’ll Learn:

  • How Expansion Tank Works.
  • Complete Guide About Thermal Expansion Tank And Why You Need It.
  • How Beneficial Expansion Tank Is.

Listen To The Audio

Enjoy this transcript below!

Troy: And Cole with Champion Plumbing. We’re going to talk about expansion tanks. We’ve been seeing a little bit more about it. Cole’s got one cut out and he will fill you in.

Cole: All right. So this is a thermo expansion tank. Typically, they hang up on the water heater, cold side, right up here. What they do, so you always have pressure in your home, heated tank heats up. You get more pressure for it. So there’s a diaphragm in here, where this has PSI of air in it, equal to the pressure of your home.

And then, this bladder will move up and down with the rise in temperature of the water, and wants to expand your water pressure. If you don’t have one of these, some people have to have them, we usually don’t put many in on water heaters. We never have an issue.

Troy: Why is that?

Cole: It’s a good question. A lot of houses don’t have a pressure-reducing valve right here. If you have too high a pressure coming into your house, this will limit the pressure into your home. With one of these, your water can’t flow back to the city water. If you’re running the water, you’re pulling it from the city. When you shut it off, it could bounce back into the city. If you have one of those, it’s going to lock it up, so it’s stuck in your home.

So you’re making a big loop where, if no fixtures are running, you have no place for water to go. And then you’re heating water and it wants to expand, and it needs to go somewhere, so therefore you have one of these.

We have homes with pressure-reducing valves that don’t need one of these. And we have homes that don’t have pressure-reducing valves or a thermo expansion tank. This one was in a home. It was leaking. We needed to order one so we capped it off. Within a few hours, it was leaking out of their T&P pipe right here. This is a safety relief valve on your water heater.

Troy: Temperature and pressure relief valve.

Cole: If that gets too high a pressure, it’s going to bounce out here down to the floor. It’s just a safety device. So we had to go back and put a new one of these ones on. Some of them come pre-charged to a certain PSI. But always get a gauge, put it on your water heater, or on your laundry tub faucet, or your outside spigot.

Troy: Find the PSI.

Cole: Get your PSI reading of your home. And most of these either have a cap or they don’t. You just use a bike tire filler upper, check your pressure, equal to your home.

Troy: That’s important. So you want to check your pressure at your home. Say you have 60 PSI in your home, you want to pump that up to 60 PSI?

Cole: Yes, absolutely. Now, I have heard some people go two PSI below what the normal house is. Most of these are going to have instructions. Just follow the specs of what the tank that you buy tells you to do, is going to be your best option.

Troy: Always your best option. Good advice.

Cole: Always.

Troy: And I do know that some of these pressure-reducing valves do allow pushback onto the city. So check the manufacturer’s recommendations on them as well. But in a closed-loop system, like in a boiler system, that’s usually where we see these, isn’t it?

Cole: Yeah, usually, always boilers we have these, closed-loop. In your home, your closed-loop, but you do have faucets you’re constantly turning on and off, flushing toilets. Water’s always moving. I’d say more phone calls we get of this leaking out, or something like that is at nighttime. No one’s using the water. It’s all done for the day. That’s when the pressure is starting to build up in your home.

Troy: Right. So thermo expansion, when the water heater or the boilers start to fire up, that’s when the thermo expansion will happen. And it creates pressure inside. If you have one of these, the bladder will just absorb that pressure and you won’t have any problems. If you don’t, you could potentially get the T&P to spit and sputter, just to relieve the pressure. And then it’ll close back up if it’s operating properly.

Cole: And then, if you do have one of these in, everything’s fine with it, and we’re out to replace a water heater, we’re going to replace this. The customer that this one came out of, they had a different company replace their heater. They never replaced this. And it shot pinholes of water all over their basement, wrecked a bunch of old pictures and photos and stuff they had. So they’re pretty beat up about it.

Troy: Something simple.

Cole: You can see the rubber bladder and the thermo expansion tank itself, it’s not very thick metal. And water, air, is bouncing around in there. Over time, it’s going to wear out.

Troy: Well, there you go. Thermo expansion, expansion tanks, why we do and don’t need them. In our Metro Area up here in Minnesota, we don’t see a lot of them. We have been seeing some cities… I don’t know if it’s the building or what they’re doing. But some cities, including our operations manager in Farmington, we had to put one in because his T&P kept sputtering and sputtering. And what was the other city you saw it more recently in, Cole?

Cole: It was in Lilydale.

Troy: Lilydale, is that somewhere by St. Paul?

Cole: Yeah, between, basically, Eagan and St. Paul, is the little town of Lilydale, through that stretch there by the river.

Troy: There you go. I think I’ve seen the sign. So again, Champion Plumbing out of Eagan. We do service the entire Metro Area. If you’re having water pressure issues, you need a water heater, or any plumbing needs, who do they call?

Cole: Call us, Champion Plumbing, 651-365-1340. Up on the web: Check out YouTube, got a lot of videos on there.

Troy: And click that subscribe button. Thanks, y’all.

Professional Plumbing is Just a Click Away!

We work Monday through Friday: 7:00 AM – 5:00 PM and Saturday: 7:00 AM – 12:00 PM. After hours emergency service is available. You can find us at 3670 Dodd Road in Eagan, MN 55123 during our open hours. You can also call us at (651) 365-1340 or email us.