I'm in Hot Water (Again!)

I've been really busy at work, while trying to find time to prep for our next big project at the house, so the last thing I needed was something else to work on.  Naturally, it was the perfect time to walk downstairs and find a big puddle of water under my water heater!

When we bought our new home, we knew the water heater was installed by the builder about 15 years ago.  Since any water heater over about 10 years old is living on borrowed time, I knew I'd have to replace it before too long - I just didn't know exactly how soon I'd be working on it.  Installing a water heater isn't difficult, but make sure you follow all applicable building codes.  You may be required to get a permit - check with your local department of building and safety if you're not sure of the requirements in your area.

The leak wasn't too bad, but water heaters rarely heal themselves, so I decided to pick one up on the way home from work and install it that night.  If you're in the market for a new water heater, there's a few things you need to think of:

• Gas or Electric?  That's an easy decision, in most cases.  In most cases, you'll want to replace your water heater with the same type you're removing.  Switching from gas to electric will require adding a dedicated circuit for the heater, and will probably end up costing you more for operating costs.  If your old heater is electric, you may be temped to install gas to save energy costs.  Unfortunately, you'll have to run a gas line, as well as an exhaust vent, making your installation more difficult and expensive.
• Capacity?  A standard water heater has a storage tank where hot water waits for your use.  Generally speaking, the larger the tank, the greater the capacity.  A tank that's too small may mean you'll run out of hot water, while an overly large tank will just end up costing you more in operating costs.  Water heaters are also rated as to how long they take to heat water to normal operating temperature.  In most cases, you'll want at least as large a tank as you're replacing - larger, if you've added a whirlpool tub or some other hot water hog.
• What configuration is best?  Water heaters come in "Tall" and "Short" models.  There's no inherent advantage to either style, but it can make a difference in the ease of installation. 
• Warranty length / quality.  Unlike some other products, a longer warranty in a water heater generally means it is a higher quality unit.  In most cases, it doesn't pay to buy the very cheapest unit.  While I don't always buy the very top quality, I find the best value is generally in a "middle of the road" line.  In this case, I bought the "9 year" heater, which cost about $100 more than the low-end "6 year" model.    This model had a higher  BTU rating than the cheaper one - equivalent to the higher end model at Home Depot.  If you're so inclined, there are premium models available at a much higher price - evaluate them and choose what makes the most sense for your application.
• Other options.  There are other options available - Tankless heaters, solar heaters, and small, point of use heaters.  All of these may make sense, but are probably beyond the ability of most homeowners to install.

In my case, choosing a water heater was easy.  We had a 40 gallon natural gas water heater that, when working, provided adequate capacity.  Access to the unit was good, since it is installed in my unfinished basement.  As I mentioned above, I bought a "mid grade" model.  I chose a "short" heater, since having a new water heater slightly shorter than the old one simplified installation slightly.  I also measured the distance between the inlet and output ports, to make sure they matched up with my existing pipes.

When I bought the water heater, I also bought fittings and supplies needed for installation.  in my case, since I was going to solder 3/4" copper pipe, I bought a bunch of elbows and couplings, along with a couple of 3/4" pipe thread adapters.  Since I'd be working in the evening, I bought extra fittings - nothing is more frustrating than needing a fitting when all the stores are closed!

For tools, you'll need:

• A tubing cutter to cut rigid copper tubing
• Wrenches matching your fittings (or a couple of 10" crescent wrenches)
• Teflon tape for both water and gas connections.
• A portable propane torch (if you're going to solder connections), along with lead-free solder, flux, and associated tools.  If you look at the  hardware store, you'll find kits with everything you need to solder copper pipe.  Make sure you get the proper size tool for your size of pipe.
• A drill and nut drivers to remove and reassemble the exhaust vent pipe.
• Safety glasses!
• Leather gloves

After dinner, I headed downstairs to install the water heater.  These instructions are based on a standard installation with rigid copper tubing.  If your situation is different, some of your connections may be different:

• Remove the carton, and make sure your new water heater isn't damaged.  Now is a good time to double check your fittings to make sure you've got what you need.
•  Identify the incoming cold water supply line on your old water heater.  If you can see your plumbing, just follow the pipes back to the water meter (or the water softener, if you've read my blog before).  If you can't easily follow the pipes, just turn on some hot water, and you'll be able to feel which pipes are getting hot - that will be the output side.
• Turn the water heater off, shut off the gas supply, and disconnect the gas pipe from the heater (assuming, of course, it's a natural gas unit).  If it's electric, lock out the breaker and disconnect the power)
• Remove the sheet metal screws holding the vent piping to the unit, and set it aside for later use.  Now is a good time to inspect it and make sure it's clean and in good condition - a faulty vent can lead to carbon monoxide poisoning, so don't skip this step!
• Turn off your water supply.  There should be a water shut off on the pipe coming into the water heater - you can shut it off, and you should be good.  If there isn't a shut off, or if it doesn't work (not unusual), you'll have to shut the water off at the main shut off.
• With the water off, open the drain at the bottom of the water heater to let the water start draining (this assumes you have a floor drain by the heater - if you don't, you'll want to hook up a hose so you can let the water drain into the drain).  Not much water will run out, but that's OK - we'll take care of that in the next step.
• Take your tubing cutter, and cut the water lines on the top of the water heater.   If the fittings are the same as on your new unit, cut the pipes 6-10" above the heater - you can just use them again, and solder it back together with a coupling.  If the fittings are different, just cut them close to the water heater - you may end up cutting them shorter later, depending on the particulars of your installation.
• As soon as you cut the pipes, the water will drain from the water heater.  Let it drain, then move it out of your way.  Now, you're ready to install the new one.
• Set the new water heater in place, making sure it's sitting flat and level on the floor - if not, you'll need to level the floor before you install it.  You CAN'T just shim one side to get it to sit level - it needs to be fully supported before you fill it with water.
• Measure the distance from the pipes to the fittings on top of the unit.  If you're soldering connections, you'll want to have at least 6" above the water heater to solder your connection - more is better.  If there's not enough room, cut the pipes to give yourself room to work.
• You can't solder fittings that are attached to the water heater, so you'll need to do those first, then install them.  Cut the pipe for a proper fit, and, using the proper tool, clean the end of the pipe and the fitting, then coat both with flux.  Slide them together, and get your torch out.  Do the smart thing, and put on your safety glasses and leather work gloves now!
• To solder the fittings, apply heat to the junction of the fitting and the pipe, so both heat up.  Don't apply the solder until the parts are hot enough to melt it - if you do, you'll just melt solder over it and end up with a cold joint.  When the parts get hot, the solder will melt and be drawn inside the joint.  You don't need too much solder - once it starts, it will quickly fill the joint and start dripping on the floor.  Be very careful not to let any drip on your hands or body - serious burns can result!
• As soon as you've applied enough solder (you'll probably overdo it at first, but that's OK), wipe away any excess solder outside the joint with a damp rag.  The extra solder won't hurt anything, but it will look ugly (I'm an expert on ugly solder joints).
• When you have your two short pieces of pipe with fittings attached, let them cool for a couple of minutes before installing them on the water heater.
• Before installing the fittings with pipe on the water heater, prep the pipe ends and couplings.  You'll want a slip coupling, so you can slide it up the pipe and out of the way until the fittings are tightened.
• Put several wraps of Teflon tape around the male pipe threads, then install the fittings.  Pipe threads are an interference fit - they get tighter as they go together, so you'll want them very tight.  The Teflon tape helps them slide together.
• After installing the fittings, you should have just a small gap where the pipe was cut.  Slide the couplings so they cover the gap.  Before soldering, wrap a wet rag around the fittings installed on the top of the water heater to protect it from getting too hot.  If that fitting gets overheated, it will ruin the fitting inside the unit, so you'll need to be careful.  I also spread a damp rag to cover the top of the heater to keep it from getting ugly.  Solder both sides of the coupling on each side.  Your water connections are complete - you can turn the water on now.  Before you do that, open a hot water faucet a little bit, so the tank will fill completely.
• Hook up the gas line, making sure to use the proper Teflon tape on any pipe threads (Teflon is not required on compression fittings).
• Assemble the vent piping, making sure there is a slight upward angle of the pipe as it goes away from the water heater.  Make sure everything is lined up properly, then use small sheet metal screws to keep it all together.
• Turn on the gas, and check for leaks using a soapy water solution.  If it leaks, the soap will make bubbles - if you see any signs of that, shut off the gas and fix it!  Follow the instructions with the heater, and light the pilot light.  Adjust the temperature to a medium setting, and turn the unit to on - the burner should light. (of course, if you've got an electric water heater, you'll hook up the wires and turn on the power)
• Check again for gas leaks - shut the gas off if there's any sign of a leak!
• Let the unit run until the burner shuts off, and you've got hot water!

If you don't want to solder connections, Home Depot sells "water heater connection kits" that use compression connections and flexible tubing that eliminate the need for any soldering.  They work fine, and there's nothing wrong with using them if you're more confident in your ability to get the job done with them.

Installing a water heater isn't hard - a reasonably handy homeowner can accomplish it in a matter of a couple of  hours.  My installation, from beginning to end, took about 2 hours.