Should I Install An Expansion Tank?

[D45]

I installed a new water heater last summer......40 gallon Richmond, 9 year warranty

The last one (40 gall, Richmond) was 14 years old and did not have an expansion tank

Do I need one?

Should I install one?

My house water is from a community, treated well to make the water potable.......no water meter at my house, flat rate monthly bill

I have a whole house sediment filter

 

[rlitman]

Do you have a check valve or RPZ or the like? If you don’t have something to prevent expanding heated water from traveling backwards through your main, then you don’t need an expansion tank.

I would consider installing a ground wire from the cold copper to the hot copper though.

 

[AA7483]

x2. As long as the expanding water has somewhere to go its fine. But it cant hurt to have one even if its not a closed system. Some municipalities require it though. You should check local code.

 

[D45]

Do you have a check valve or RPZ or the like? If you don’t have something to prevent expanding heated water from traveling backwards through your main, then you don’t need an expansion tank.

I would consider installing a ground wire from the cold copper to the hot copper though.

I don't believe there are any check valves, anywhere, to my knowledge

Explain the ground wire, please........the old one didn't have any grounding wires

 

[rlitman]

I don't believe there are any check valves, anywhere, to my knowledge



Explain the ground wire, please........the old one didn't have any grounding wires

You have dielectric unions. The cold pipe should be grounded already, but the hot isn’t, since the unions will not allow electricity to flow past.

 

[Richard Cranium]

as long as you don't have a closed (one way) system, you don't need to spend the money.

 

[cdestuck]

Not if your temperature relief valve doesn't spit out water now and then. I've never had one on mine or any of the many Ive replaced

 

[LS6 Tommy]

Just so there's no confusion of terms, the copper doesn't get "grounded", it gets "bonded". Code requires all metallic water piping to be bonded at the electrical service. Since the hot and cold domestic water are isolated by the dielectric unions on the water heater, they must also be bonded to each other. The sizing of the bonding cable has to be sized according to your service amperage rating and a few other factors that I'm not qualified to determine. I would consult a licensed electrician.

Tommy

 

[kbs2244]

I have never seen a "bonded" water heater.
If you use the required cold water piping system as a ground you would not need it.

 

[fsae0607]

If there's no check valves (as mentioned) or pressure regulator you should be ok.

For shiznits and giggles, maybe put a pressure gauge somewhere in your system and see what the pressure does after your water heater kicks on to recover. If there's no pressure spikes, then you're good.

 

[D45]

I have a pressure gauge installed, after the sediment filter.....basically to help me determine when the filter needs to be changed

 

[rlitman]

Does it have a re-settable needle that shows the highest pressure reached? That's what you need to detect spikes in pressure.

 

[Dirtydan69]

I worked on a house the other day that had the coax bonded to the sill ****. House is all pex inside.

 

[rlitman]

I worked on a house the other day that had the coax bonded to the sill ****. House is all pex inside.

LOL. My coax used to be bonded like that. When recently switching to PEX, I brought a ground wire there, and sank another ground rod for good measure.

 

[6768rogues]

I have a pressure gauge installed, after the sediment filter.....basically to help me determine when the filter needs to be changed

If that is what you use you should always check it with the same water outlet running. That will give you the residual pressure which will deteriorate as the filter gets dirty. If you check static pressure it will only vary with supply pressure variations.

 

[engineer2]

I've never heard of bonding a gas water heater that has no power going to it. The incoming water line is bonded, so hot and cold plumbing will be at the same electrical potential via every fixture in the house.

 

[kbs2244]

PEX is going to create a need for a lot of code re-write.

 

[Markfothebeast]

YES! Install an expansion tank. It's cheap insurance to human life and the life of the water heater. Most cities had begun installing check valves from the main. This may not apply everywhere but it's a common practice.

That water pressure requires somewhere to relieve when it can't push back in to the city water main. I'd seen some water heaters that looked like hell and had leaked internally and from fittings - thankfully did not blow up. The prrssure relief valve was corroded shut. For $30 - $50 for an expansion tank it's worth it. The fittings probably cost nearly as much.

-Markfothebeast-
(www.youtube.com/markfothebeast)

 

[Markfothebeast]

I installed a new water heater last summer......40 gallon Richmond, 9 year warranty

The last one (40 gall, Richmond) was 14 years old and did not have an expansion tank

Do I need one?

Should I install one?

My house water is from a community, treated well to make the water potable.......no water meter at my house, flat rate monthly bill

I have a whole house sediment filter

Other than expansion, how's the pitch on that draft flue? Hard to see. I commonly see flues improperly installed. And even sometimes a cold air return grille nearby overcoming the draft.

-Markfothebeast-
(www.youtube.com/markfothebeast)

 

[mygarageone]

Other than expansion, how's the pitch on that draft flue? Hard to see. I commonly see flues improperly installed. And even sometimes a cold air return grille nearby overcoming the draft.

-Markfothebeast-
(www.youtube.com/markfothebeast)

If you look close , you can see there is pitch

 

[gahrajmahal]

In Ohio (hi neighbor) I believe it is code to have both a back flow preventor and an expansion tank. My understanding is it minimizes water hammer. Your copper looks to have some years on it. An expansion tank will minimize undue pressure to the joints, most visible when the washing machine is running, turning on and off abruptly the hoses visibly jump with the pressure spike.

 

[Markfothebeast]

If you look close , you can see there is pitch

My fault. I'm on mobile.

-Markfothebeast-
(www.youtube.com/markfothebeast)

 

[lml999]

Other than expansion, how's the pitch on that draft flue? Hard to see. I commonly see flues improperly installed. And even sometimes a cold air return grille nearby overcoming the draft.

-Markfothebeast-

We bought a house two years ago that had an 80 gallon gas fired water heater installed. It had been installed three years earlier, probably replacing a smaller capacity tank.

When we first looked at the house, we smelled gas in the basement. Asked the seller to have it checked.

After we moved in, we continued to smell gas intermittently. We had the company that installed the tank come back and try to tweak the setup.

The problem was that the larger tank was too tall...we had no vertical run on the vent and barely enough pitch on the horizontal. The tank wasn't creating enough draft and exhaust gases were backdrafting into the basement.

I don't know how it passed inspection... Oh, it didn't. No paperwork at town hall. Done in the dark of night, lots of finger pointing.

Also not sure how the previous owner lived with this for three years. The basement is (recently) finished (also without any evidence of permitting) and appears to have been used a fair amount.

Farck.

So we pulled the heater and replaced it with an indirect tank, heated off a zone on the furnace. No more gas smell. D'oh.

Lessons learned.

 

[Markfothebeast]

We bought a house two years ago that had an 80 gallon gas fired water heater installed. It had been installed three years earlier, probably replacing a smaller capacity tank.

When we first looked at the house, we smelled gas in the basement. Asked the seller to have it checked.

After we moved in, we continued to smell gas intermittently. We had the company that installed the tank come back and try to tweak the setup.

The problem was that the larger tank was too tall...we had no vertical run on the vent and barely enough pitch on the horizontal. The tank wasn't creating enough draft and exhaust gases were backdrafting into the basement.

I don't know how it passed inspection... Oh, it didn't. No paperwork at town hall. Done in the dark of night, lots of finger pointing.

Also not sure how the previous owner lived with this for three years. The basement is (recently) finished (also without any evidence of permitting) and appears to have been used a fair amount.

Farck.

So we pulled the heater and replaced it with an indirect tank, heated off a zone on the furnace. No more gas smell. D'oh.

Lessons learned.

This is common. This design needs to be replaced with something safer. I've run in to situations in some homes where just opening a window created enough negative air pressure to overcome the draft - or even a nearby clothes dryer.

-Markfothebeast-
(www.youtube.com/markfothebeast)

 

[peter2772000]

I really need to stop visiting this site, I keep finding more things to be anxious about afterwards.

In Florida, I had our hot water tank replaced right after we purchased our home in 2012. Had been given a set price over the phone but as is usually the case, the plumber had an extra for me. Informed me that it was code to install an expansion tank, which the old set-up never had. So he did.

Always had an issue with the time it took for the hot water to reach the dishwasher (resulting in badly-spotted glasses) and guest bathroom. At the recommendation of a neighbor, I installed a kit which is comprised of a small pump in the hot water line just off the tank, and a thermostatic valve near the dishwasher. Added a 2nd valve for the guest bathroom.

I'm talking about this-------- https://www.lowes.com/pd/Watts-Water-Heater-Recirculating-Pump/1100949

Thing works super. Consumes pennies for electricity and is on a timer.

Anyhow, seeing as this worked so well down south, I did the same install up here in Montreal with the same wonderful results. Only thing is, we don't have an expansion tank up here. We're on city water just as in down south, but I personally have never seen expansion tanks on city-water set-ups. Do I absolutely need one?

 

[D45]

Seems like there is no solid answer, but it also seems like it certainly wont hurt to have one

I talked with a few neighbors, some who have lived in my neighborhood for a long time..........some have them, some don't

 

[pilotmotor]

I made a simple mod to a standard gauge to test for this years ago. Just drill a small hole in the center of the plastic gauge cover and bend a paper clip into a z shape , feed it through the hole and let the sweep of the needle move it in an arc.It will record the highest reading. Lay the gauge flat and let the water heater run normally. I left mine on for a few days and found my system going up to 90lbs , i have a reducing valve set to 40lbs with a check on the water inlet. I installed the expansion tank and it never spiked after that.

 

[D45]

Should the expansion tank be installed riggt at the hot water heater, way before it, after it?

It's only on the cold water side right?

Are these expansion tanks all the same or are there certain features to look For? Sizes?

My water pressure, before the hot water heater is usually.
around 60-70psi

The pressure release valve on my tank is 150

It really sounds like I don't need it......i am fairly confident I dont have a backflow valve

 

[pilotmotor]

Could be installed anywhere on the cold water line technically but code in your area may dictate exactly where it must go.It could also work on the hot side just wouldnt live as long a life i would imagine. They make special ones for "Potable Water" thats what you need. 60-70 psi sounds high to me , that would take its toll on your plumbing fixtures . I always set mine to 40lbs By the way im not a plumber so take what i say with a grain of salt

 

[rlitman]

The hot side won’t hurt it. Extrol tanks are standard parts on boilers, and hydronic systems get far hotter.

 

[D45]

PSI is actually closer to 55-58, I checked this morning

I have no way to adjust it

 

[JMartel]

Current code most areas say that you have to have a backflow preventer valve and an expansion tank. You really don't want to have any water being pushed back to the street. I re-plumbed my whole house last year. It's easy enough to add and not expensive. Maybe $150-200 tops for everything.

 

[peter2772000]

I have a "backflow preventer" up here in Montreal, but only on the water line out in the garage. I was told by the plumber who did the plumbing in the house that it was code. Seems that when people were using high-pressure sprayers connected to the garage water line and the sprayer was idling, water would back-feed into the cold-water main. If you had a soap mixture in the sprayer reservoir, that would end up in the mains as well. Kinda hard to imagine, but it must be possible.

I think I'll pick up an expansion tank to be safe. Can't hurt, right?

 

[peter2772000]

I made a simple mod to a standard gauge to test for this years ago. Just drill a small hole in the center of the plastic gauge cover and bend a paper clip into a z shape , feed it through the hole and let the sweep of the needle move it in an arc.It will record the highest reading. Lay the gauge flat and let the water heater run normally. I left mine on for a few days and found my system going up to 90lbs , i have a reducing valve set to 40lbs with a check on the water inlet. I installed the expansion tank and it never spiked after that.

Hilarious, and ingenious LOL

 

[D45]

Current code most areas say that you have to have a backflow preventer valve and an expansion tank. You really don't want to have any water being pushed back to the street. I re-plumbed my whole house last year. It's easy enough to add and not expensive. Maybe $150-200 tops for everything.

Current code for municipal water or code for a community on the private well?