7 Steps For Apollo Hydroheat Water Heater Replacement

Are you getting rusty and smelly water from your Apollo water heater? Here the only solution is the Apollo hydroheat water heater replacement. But do you know the replacement procedure?

apollo hydroheat water heater replacement

If not, stay with me. I will share how you can simply replace your hydro heat water heater by yourself without any help from a professional.

Be patient and let me start! Keep reading, you will definitely get simple solutions as you got with Polaris water heater problems & errors.

Apollo Hydroheat Water Heater Replacement: A Complete Guideline

The Apollo HydroHeat water heater provides hot water with the help of a high-competency gas water heater to an air handling system. 

This gas water heater circulates the water through a water-air heat exchanger. It is better to have a look at the Apollo Hydroheat water heater manual to know the basic things to replace it. 

If that doesn’t work, here I’ve described the apollo heating system replacement for you: 

Apollo Hydroheat replacement parts that you will need:

  • An adjustable wrench & a 4-in-1 screwdriver
  • An electrical tape & plumbers tape
  • Pipe wrench & soldering torch
  • Safety glasses & fittings
  • Voltage tester & tape measure
  • Tube cutter & wire stripper/cutter
  • Discharge pipe & materials required
  • Pressure relief valve & pipe thread compound
  • Solder
  • Water and gas piping
  • Venting pipe & connectors

Step 1:

Turn off the gas valve to shut the gas line off with the water heater. Now shut the main water supply off. Open a faucet and drain the lines. Then drain the tank water.

Attach a hose with the drain valve to drain the remaining water from the tank. But be careful! Water will be burning hot. So you need to separate the gas line from the gas control valve using wrenches.

Step 2:

Disconnect the waterline by unscrewing the vent pipe and keeping it aside. Cut the cold and hot water lines using a tube cutter. After that, slide out the old water heater.

With the help of Teflon tape, wrap the fibers of temp. and pressure relief valve. Screw it compactly in the tank using a pipe wrench and attach a copper discharge pipe.

Step 3:

Solder the new copper adapters, and screw them to assemble into a hot water outlet as well as a cold water inlet to the top. Add short and plastic-lined nipples and shield against galvanic corrosion.

Now slide your new water heater into its place, and extend the old tube to attach with the new one. Finally, solder them together with copper slip couplings. 

Now it’s time to reconnect the vent. Shove the vent tightly over the draft hood, and anchor it with metal screws. 

Step 4:

Attach the gas line by coating the threaded ends with the help of a pipe joint compound. After that, screw the first nipple to the gas valve using two pipe wrenches. Now fill the tank with four steps:

  • Closing drain valve.
  • Turning on the water back at the main shutoff, and opening the cold water valve of the water heater.
  • Turning on a hot water faucet until the water comes out.
  • Inspecting the joints and fittings. 

Step 5:

Usually, water heaters rely on natural drafts and create combustion fumes. If the draft is out of service, the fumes will spread out carbon monoxide to your home. 

So, do not forget to check the back-drafting after a water heater installation.

  • Close the windows and doors of your home. 
  • Turn on the exhaust fans of the bathroom and kitchen.
  • Open the nearby hot water faucet until the gas burner ignites. 
  • After some time, move a smoking match near the draft hood edge.
  • The smoke should draw up to the pipe of the vent. 

If the smoke does not draw, it indicates the burner is not venting. You will need to call a plumber to fix this problem. 

Step 6:

The next step is to check whether your apollo hydroheat water heater leaking or not. Turn the gas on, and brush a water-dishwasher mixture over the joints. If you notice any bubbles, it indicates leaking.

Step 7:

Light its pilot light following the manufacturer’s advice. Adjust and set the temperature. Finally, you are done with your apollo hydroheat replacement parts. 


If you have aluminum wiring, you need to consult with a licensed pro to handle it. The wirings will be dull gray, not as orange as the copper ones. 

This is how you can replace the Apollo hydroheat water heater. Obviously, the process seems easy to read, but it’s not that simple. You will need to work 6-7 hours or a full day to complete this task.

When You Should Replace Your Water Heater?

When the tank of your water heater leaks, it is considered dead. Also, your water heater needs replacement if it has a slow drip underneath that is a sign of rusty water. 

If the steel tank becomes rusted, it is recommended to replace the heater. Also, if you notice insufficient hot water or a complete absence of hot water, your water heater needs replacement. If you see any of these signs, don’t wait for a worse situation.

Replace or fix it as early as possible. Nowadays, new heaters come with manuals containing installation instructions. Also, you will find some warnings, precautions, and many more details. So it won’t be difficult to conduct at all for you.

How is the Apollo Water Heater Replacement Cost?

Many people ask about the cost to replace the apollo water heater. Well, usually the plumbers charge $45-$65 per hour. They take not more than eight hours to complete the installation process. However, gas and electric heaters won’t cost the same. 

What are the Signs of a Hot Water Tank Going Bad?

You can easily tell if the water heater is going to collapse by observing some signs. It will lower the cost and hassle as you will be able to avoid the sudden breakdown of your water heater.

Here are the most common signs of a water heater going bad:

1. Leakage of Water from the Tank:

Any type of leakage, like water dripping from the pipes or from the heater tank, may occur when the water heater is in a bad condition. It usually indicates an internal issue. Maybe the valves are not closed properly, or the connections may be loose. 

2. Discolored or Smelly Water:

Rusty water, water mixed with mercury, discoloration of the water, rotten egg-like smell, and muddy hues are unusual things for your water heater. Bacteria or rust may be the cause of these abnormal smells and colors. 

It is possible when the anode rod of the heater (that removes rust and bacteria) is broken. You can replace the anode rod and get rid of this problem easily. 

3. Running Out of Water:

Sediment may settle down at the bottom of the tank if you don’t flush it regularly, resulting in a shortage of space for the hot water. That’s why the water runs out within a few moments. It will also cause reduced water flow. 

If the water heater remains untreated for a long time, the valves will become corroded and clogged and will be difficult to repair. 

4. Inconsistent Temperature of Water:

The inconsistent temperature of the hot water is another sign of your heater going bad. In this case, sometimes you will get too hot water, sometimes cold or at normal temperature. 

It may be due to the disturbance of the thermostat. If you replace the thermostat, it won’t create any issues. However, this problem may also occur if the heating element is broken. In that case, you will need to replace the whole unit.  

5. Concerning Unusual Noises:

If the heater element is broken, you will hear a strange sound from the water heater. Also, the sediment build-up can clog the system and create an unusual sound. 

If the water pressure changes frequently, or the valves are connected loosely, you can hear an abnormal sound, too. These sounds indicate that something is not going well.

6. Age of Your Water Heater:

If your water heater is more than 10 years old, it is about to end its journey. Preparing yourself mentally to replace the water heater is a good decision. Also, take care of the heater to avoid any unwanted issues.

Well, to know more, you can watch the video given below.


Can I replace my hot water heater myself?

Yes, you can, but make sure you are confident enough to do this job. But you should attain a permit and have to have the practical knowledge and abilities you need for this task. Also, this process may cost you some more. If the concern is about the budget, you should seek professional help as it is the safest and most affordable option at the same time.  

Is it cheaper to repair or replace a water heater?

To decide whether it is wise to repair or replace the water heater, you can follow a simple rule— if the repair cost is 50% of the replacement or more, repairing won’t be the wise thing to do. Also, old models of heaters that already lasted 10-13 years will make a huge cost if you go for repair. But, if the water heater is not that old, repair will be the cheaper option.   

Should I replace my 15-year-old water heater?

It is recommended to replace a water heater if it is 12+ years old. However, if you don’t see any abnormalities, like running out of hot water or lack of hot water, you’d better replace it.  

Should I repair a 10-year-old water heater?

It depends on some conditions. Usually, the lifespan of a water heater is about 12-14 years if it is well maintained. If you don’t take care of the water heater that much, it will collapse within 10 years. However, if you find that repairing your 10-year-old water heater will cost a lot, it is wise to replace it. Or, if the water heater has minor issues, you can go for a repair process as well.

How long do Apollo water heaters last?

A water heater with a tank can perform well for up to 10 years. But, a tankless water heater lasts about two times longer. You can use a tankless water heater up to 20 years. 

How often should my water heater be serviced?

Just like other appliances of the house, you need to take care of the Apollo heating and cooling systems through professionals once a year. It is recommended to drain and remove the sediment from the water heater annually. It facilitates a great hot water supply to your home. 

Can you drain a tankless water heater?

Yes, you can. Some water heaters indicate when they need flushing. It will take about one hour to flush a tankless water heater. You will need to turn the electric circuit. Or, if it is a gas water heater, turn the gas off by rotating the gas cutoff to drain the heater. 


Apollo hydroheat water heater replacement is a moderately complex procedure, especially if you haven’t done any task like this before. 

So, keep your eyes on every step we have shown. We can assure you, you will be capable of doing the replacement task perfectly and effortlessly. 

However, if you are not confident enough, then you can call a professional to replace the water heater.

About William

William is the founder of Fireplacehubs.com. He has real life practical skills in fixing smoker & heating appliance issues. He loves to share his knowledge & helps others in fixing their appliances & saving their money. William firmly believes that anyone can repair his or her unit with the correct guidance & knowledge. See more at about us.

8 thoughts on “7 Steps For Apollo Hydroheat Water Heater Replacement”

  1. I have two New Old Stock 40 gallon, 38,000BTU Apollo Hydroheat water heaters, still in their unopened boxes. You can no longer purchase these water heaters. Let me know if you are interested.


Leave a Comment