May want to read up on the term "Orphaned Water Heater". Your situation is very common.

 

1) Yes you need a liner
2) No
3) NO
4) Heat Pump Water Heater

 

I should ask, is this chimney inside the house or run up an outside wall?

 

hi, its run up the outside of the house

 

Isn't your hot water chimney orphaned all summer long ?

 

Mine..........NO :grin2:

 

That should've been water heater does that change anything 😃
Of course we don't heat hot water 😉

 

The water heater is not an orphan. It was an abused child by its uncle but now it is grown up and able to live a normal life.
Water heaters have hotter flue gases when furnaces are removed because there is no mixing of dilution air from the idle furnace. Water heaters have operated 90% of their life in the flue with the furnace idle with no problem. But someone thinks there is a magic tonic to make it better because it got sick when its uncle left.

 

Did you miss this post ☝🏻

 

Should we go over the problems with cheap liners 🙄

 

If the fireplace is wood burning it may not share the same flue space in the chimney with other appliances. That part needs to be corrected.

 

A chimney lining costs money and provides a limited and un-reasoned value for the funds. Rather than spend the money on a chimney liner - I would prefer to see it spent on something which will provide an active benefit to you - such as a tankless water heater.

A chimney liner allows you to stay with last century's technology - which makes no sense to me if it can be avoided.

There are other options to avoid living the chimney, such as a power-vented tank-type water heater - or a a heat pump water heater.

With natural gas available - my strong vote is: tankless water heater.

PHM
-------

 

What type of water heater is this that was using a chimney with an oil furnace attached to it?

Is this an oil fired water heater, or propane?

 

gas water heater venting out the chimney along with a oil powered furnace (to be converted to a direct vent gas system)

 

1. If the water heater stays connected to it, yes.
2. You could get a power vented water heater (which vents out the side of the house in PVC). They are more expensive and tend to be noisy but if you have an oil fired heater now you won't notice.
3. 100% NO, please don't attempt that.
4. You could install an electric water heater (I see these often in houses with oil furnaces). No exhaust to connect. There's also tankless heaters, which also vent out the side of the house and provide nearly-limitless hot water. They're the most expensive option but if you need loads of hot water they're nice.

BTW is the fireplace gas or wood? Not sure what code is in your area but code may not allow the fireplace and water heater to be vented together.

 

.

 

Edited,, I said essentially the same as others..
tankless, powervent or heat pump


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I figured it was an oil since same flue. I have seen (gas) water heaters, with and with out furnace that would not draft in summer due to large size of flue. usually upper 80s and higher outside.

side wall venter from tjerlund for oil, but cheaper to get new wh. gas direct vent instant or elec instat wh are options. as another said, can get away from chimney since they are constant on exhaust fans pulling air out of house, and the wwarmer inside/colder outside the more air they pull out house.

the instant elec are tiny, like getting an extra closet when the tank goes away.

 

The concern is over condensation of flue gas in the chimney. This is why the rules are sometimes different for interior chimneys (completely surrounded by heated space) vs. exterior chimneys exposed to the outdoors.

In the summer, when only the water heater is running, it is warm outside, so there is less concern over condensation.

In the case of an orphaned water heater, to vent into a chimney without installing a liner, flow area can't be more than 7x the size of the water heater's draft hood. It is rare to find a water heater that will pass this test.

It doesn't matter what you think about these rules, they are the gas code, and any contractor who's not a hack will follow them.

 

Are you referring to 501.15.1 or a different code ?

 

503.5.5, size of chimneys.

 

Thanks for the info everyone, this makes sense now. Rather do it the right way than be sorry! One last question though - what about the fireplace? If you line the chimney with a smaller lining for the water heater, how would the fireplace end up working? We're not sure if we are going to keep the fireplace word burning as-is, or (more likely) put some sort of gas insert in there instead. If we do that, do you just tap into the new smaller lining? What other considerations are there?

 

A solid fuel burning Appliance can't share a chimney with a gas burning Appliance.
At least that's the way I understand it.

 

Fireplace and furnace sharing a flue against code, yes, and dangerous not even just for exhaust reasons, but fire safety as well. If there is creosote buildup in the chimney from a fireplace or woodstove, and you're putting hot flue gases from a furnace/water heater in there, you could start a chimney fire.

A single chimney might have multiple flues though, or may be able to be modified to have separate fireplace and furnace flue.

 

Does it ever make you wonder when you read the beginning of the Gas Code that states, "None of the information in this code has been checked for accuracy, correctness or of sound " Anyone using this code should use their own judgement or seek the advice of a competent professional.

In 2005 it was written in GAMA magazine, that no one writing the Codes has ever worked in the field.

If you are not a competent professional then I guess you must follow the rules that were made up by everyone's best guess.

 

That falls into the same category as Codes are minimum!

Most here know what's right and wrong, at least I hope so!

 

I always said/heard:

If you can’t do, teach
If you can’t teach, inspect

Do we need to add: if you can’t inspect write code?


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For better or for worse, the code is what's seen as "correct" by our government and our legal system. If I violate code, something bad happens (my fault or not), I get hauled into court and say "I know better than code, I read it on HVAC-Talk/heard it in my NCI class" I don't think that's going to go too well for me.

I absolutely agree that code is the bare minimum. There are all sorts of things we can and should do to make the homeowner safer, which the code says nothing about, like doing combustion analysis, and installing low level CO detectors.

But if the code says to do something, and I don't do it? Especially something major like installing a chimney liner? That's asking for trouble, if something goes wrong. And I don't think something going wrong here would be some crazy thing - I have heard stories about chimney issues after orphaning a water heater - even when the code is followed and the chimney passes the area test! Which ties in perfectly to the point that code is the bare minimum. There are real chimney problems people have had that caused these codes to be developed, imperfect as they may be.

 

would be shocked to know how little maintenance a tankless water heater needs if you add a Field Controls Clearwave to your water line. Scale is the biggest problem with them and the Clearwave has solved that problem.

We always follow Code. It states it is up to the individual using it to make necessary decision in the field to adapt to all conditions. That is Code!! It is amazing that after 42 years of field testing and equipment modifications there has never been a single incident on over 50,000 jobs I have been on or the 100,000's of jobs our students have been on. But guess where 100% of incidents were caused?

 

But guess where 100% of incidents were caused?

Blindly following code.

 

I've got a customer that wants me to flush their water heater I should offer to install a clear wave.

 

If it is still working okay, then just add the Clearwave. If they are having any problems it might need flushing first.