# Tankless Install found on Facebook



## SewerRatz (Apr 25, 2009)

I noticed Noritz on facebook, shared a photo that a plumbing company here in Illinois posted on their facebook wall. I wanted to share this photo with you all, and see what you think about the install. 

If any of you that know the Illinois Plumbing code I like to hear what you think as well. The job was in Orland Park at a Salon.


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## 1703 (Jul 21, 2009)

They are supposed to have T&P's.

Not sure, but I don't think the reliefs should be tied together. Although I have seen that approved here.


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## SewerRatz (Apr 25, 2009)

Are they required to have drip legs on the gas? Also I thought the way I am reading the code book , is a tempering valve is required with T&P valves on the tempered side. Plus a pressure relief valve supposed to be installed on the cold side. But that is the way I read the recent code.


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## 1703 (Jul 21, 2009)

SewerRatz said:


> Are they required to have drip legs on the gas? Also I thought the way I am reading the code book , is a tempering valve is required with T&P valves on the tempered side. Plus a pressure relief valve supposed to be installed on the cold side. But that is the way I read the recent code.


What section(s) are you reading that, Ron?


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## 1703 (Jul 21, 2009)

Book is in the truck and I'm too lazy to get it, but it seems to me there is a distinction made between those and a point of use, like an eemax. Maybe by capacity of heat exchanger?


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## SewerRatz (Apr 25, 2009)

Colgar said:


> What section(s) are you reading that, Ron?


 http://www.ilga.gov/commission/jcar/admincode/077/077008900I12200R.html
*Section 890.1220 Hot Water Supply and Distribution* 

7) Indirect, External, Submerged Coils. Indirect, external, tankless or submerged coils used in heating water shall be equipped with a thermostatic mixing valve or valves when not connected to a storage tank. A pressure relief valve shall be installed on the cold water inlet of the tank. A properly sized temperature and pressure relief valve, based upon the energy input rating of the coils, shall be installed on the tempered line with the temperature sensing element immersed in the tempered water line as close as possible to the mixing valve. 

8) Direct Fired Instantaneous Heaters. (Storage tank of more than 64 fluid ounces.) Direct fired instantaneous water heaters shall be equipped with a thermostatic mixing valve or valves which conform to ASSE 1017-1999. A pressure relief valve shall be installed on or adjacent to the heater. A properly sized temperature and pressure relief valve, based upon the energy input rating of the heater, shall be installed on the tempered line with the temperature sensing element immersed in the tempered water line as close as possible to the mixing valve.


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## cityplumbing (Jun 12, 2010)

I'm surprised they let you use a common relief valve discharge line.


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## SewerRatz (Apr 25, 2009)

cityplumbing said:


> I'm surprised they let you use a common relief valve discharge line.


Normally they do not. I doubt this guy had a permit, let alone getting it inspected. His company does not come up in the registered plumbing contractors in this city.


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## SewerRatz (Apr 25, 2009)

Colgar said:


> Book is in the truck and I'm too lazy to get it, but it seems to me there is a distinction made between those and a point of use, like an eemax. Maybe by capacity of heat exchanger?


Part 10 deals with the emmax point of use water heaters.

10) Point-of-Use Instantaneous Water Heaters. Point-of-use instantaneous water heaters (high temperature, non-storage or storage of 64 fluid ounces or less, non-pressurized relative to atmosphere) shall meet the following requirements: 

A) Units intended to deliver water temperatures exceeding 110°F, or with no mechanical or electrical temperature limiting device must have the faucet located at least 3 inches from the 110°F hot water or cold water faucet. All such faucet outlets shall have labels clearly and conspicuously indicating extremely hot water. 

B) Units intended to deliver water temperatures 110°F or less shall have an internal burnout element or shall have a factory set thermostat that is not adjustable to higher than 110°F.

C) All pressurized point-of-use water heaters shall also have provisions as a part of the unit to provide temperature and pressure relief. Valves shall be set to relieve at 20°F above the intended water temperature and at 125 p.s.i. or at 15 p.s.i. below the pressure rating of the lowest rated part of the assembly, whichever is lower.


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## ckoch407 (Sep 30, 2009)

Aside from the drip leg, common TnPs, and lack of PRV, the Hot and Cold piped parallel are not spaced evenly for even load draw and distribution. The Code may not require it specifically, but the manufacturer does recommend it.


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## SewerRatz (Apr 25, 2009)

ckoch407 said:


> Aside from the drip leg, common TnPs, and lack of PRV, the Hot and Cold piped parallel are not spaced evenly for even load draw and distribution. The Code may not require it specifically, but the manufacturer does recommend it.


 Tankless heaters do not need to be spaced evenly. The Noritz units regulate the flow between heaters. As for PRV around here our working pressure is around 50 to 70 PSI


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## ckoch407 (Sep 30, 2009)

SewerRatz said:


> Tankless heaters do not need to be spaced evenly. The Noritz units regulate the flow between heaters. As for PRV around here our working pressure is around 50 to 70 PSI


I meant thermal expansion valve, not PRV. :wallbash: I didnt know they regulated flow when it was imbalanced. Pretty cool feature.


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## SewerRatz (Apr 25, 2009)

ckoch407 said:


> I meant thermal expansion valve, not PRV. :wallbash: I didnt know they regulated flow when it was imbalanced. Pretty cool feature.


Well the way they work is when someone turns on a tap, the first heater flows the water and turns on while there is no flow through the second heater. As the demand increases, (more taps turned on) the first heater will tell the second heater to start flowing and turn on to meet the added demand. This is a very simplistic explanation but it works. Same thing with three four five heaters. The others do not turn on till the demand calls for it and the controller will bring in the other heaters as needed.


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## Plumber Jim (Jun 19, 2008)

ckoch407 said:


> I meant thermal expansion valve, not PRV. :wallbash: I didnt know they regulated flow when it was imbalanced. Pretty cool feature.


A tankless water heater shouldn't need an expansion tank or valve. the heater is only heating the water and causing expansion while the faucet is open. when the faucets are all closed the heater will turn off.


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## [email protected] (Apr 10, 2011)

That blue barcode label on the cold pipe suggests HD material source. 

I agree; a thermal expansion tank isn't needed (but may be technically required) for a tankless system - at least, a system without a recirc pump. Never tested for it though. Have any of you?


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## Will (Jun 6, 2010)

Colgar said:


> They are supposed to have T&P's.
> 
> Not sure, but I don't think the reliefs should be tied together. Although I have seen that approved here.



There is no need for a T&P valve on a tankless. All that is needed is a Pressure Relief Valve. A Thermal Expansion Valve is needed if the system is on a closed system.


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## ILPlumber (Jun 17, 2008)

Will said:


> There is no need for a T&P valve on a tankless. All that is needed is a Pressure Relief Valve. A Thermal Expansion Valve is needed if the system is on a closed system.


Like me Colgar is from IL. A T&P valve is required by code.

Nobody cares that this was sent from my droid using. Plumbing Zone


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## Will (Jun 6, 2010)

Sounds like someone needs to have a talk with the head of Code in Illinois. There is no point of a T&P on a tankless water heater. If that is would is required, then I understand why you would install one, it's just not doing anything.


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## ILPlumber (Jun 17, 2008)

Rules is rules...
When I order one i just order the il code model. They know exactly what i need

Nobody cares that this was sent from my droid using. Plumbing Zone


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## ZL700 (Dec 8, 2009)

"Indirect, External, Submerged Coils. Indirect, external, *tankless or submerged coils* used in heating water shall be equipped with a thermostatic mixing valve or valves when not connected to a storage tank. A pressure relief valve shall be installed on the cold water inlet of the tank. A properly sized temperature and pressure relief valve, based upon the energy input rating of the coils, shall be installed on the tempered line with the temperature sensing element immersed in the tempered water line as close as possible to the mixing valve."

When this was written it wasn't to mean to include gas/electric fired tankless hot water heaters but a tankless coil such as a tankless coil inserted into a boiler for producing DHW. In this case a thermostatic mixing valve would be needed to control fluctuating temps due to burner cycling and heating operation possibly taking place simultaneously. That is why the T&P is also required otherwise there wouldn't be a temp or pressure safety on the domestic side, heated via the boiler. 

The interpretation of the inspectors needs to be pointed out, they are wrong.

But I hear you, why start a fight with a dummy inspector that can cause you problems. But you may wish to point it out nicely and let them figure it out, to benefit all.


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## plbgbiz (Aug 27, 2010)

Will said:


> There is no need for a T&P valve on a tankless. All that is needed is a Pressure Relief Valve. A Thermal Expansion Valve is needed if the system is on a closed system.


Don't they require the T&P here Will? I never even considered installing a tankless without it. I do see your point though.

However...If the burner malfunctioned and somehow over heated, a T&P would be nice to have. For instance, is it absolutely IMPOSSIBLE for the burner to come on without proper flow of water? If so, the lack of a T&P valve could be messy.


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## 1703 (Jul 21, 2009)

plbgbiz said:


> Don't they require the T&P here Will? I never even considered installing a tankless without it. I do see your point though.
> 
> However...If the burner malfunctioned and somehow over heated, a T&P would be nice to have. For instance, is it absolutely IMPOSSIBLE for the burner to come on without proper flow of water? If so, the lack of a T&P valve could be messy.


Yeah but the temp probe of the relief isn't anywhere near the heat exchanger IF the unit malfunctioned and the burner stayed on with no flow. Would it matter? Idk.

The good book of IL says it gets a t&p so it gets a t&p. But I also question it.


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## 1703 (Jul 21, 2009)

ZL700 said:


> "Indirect, External, Submerged Coils. Indirect, external, *tankless or submerged coils* used in heating water shall be equipped with a thermostatic mixing valve or valves when not connected to a storage tank. A pressure relief valve shall be installed on the cold water inlet of the tank. A properly sized temperature and pressure relief valve, based upon the energy input rating of the coils, shall be installed on the tempered line with the temperature sensing element immersed in the tempered water line as close as possible to the mixing valve."
> 
> When this was written it wasn't to mean to include gas/electric fired tankless hot water heaters but a tankless coil such as a tankless coil inserted into a boiler for producing DHW. In this case a thermostatic mixing valve would be needed to control fluctuating temps due to burner cycling and heating operation possibly taking place simultaneously. That is why the T&P is also required otherwise there wouldn't be a temp or pressure safety on the domestic side, heated via the boiler.
> 
> ...


That's my understanding as well. Somewhere along the way, I think I was told that the new code clarifies the tankless distinction. I have no idea if that is accurate and I'll believe it when I see it.


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## SewerRatz (Apr 25, 2009)

ZL700 said:


> "Indirect, External, Submerged Coils. Indirect, external, *tankless or submerged coils* used in heating water shall be equipped with a thermostatic mixing valve or valves when not connected to a storage tank. A pressure relief valve shall be installed on the cold water inlet of the tank. A properly sized temperature and pressure relief valve, based upon the energy input rating of the coils, shall be installed on the tempered line with the temperature sensing element immersed in the tempered water line as close as possible to the mixing valve."
> 
> When this was written it wasn't to mean to include gas/electric fired tankless hot water heaters but a tankless coil such as a tankless coil inserted into a boiler for producing DHW. In this case a thermostatic mixing valve would be needed to control fluctuating temps due to burner cycling and heating operation possibly taking place simultaneously. That is why the T&P is also required otherwise there wouldn't be a temp or pressure safety on the domestic side, heated via the boiler.
> 
> ...


Ok you clarified the first part of the code, what about this part?


> " Direct Fired Instantaneous Heaters. (Storage tank of more than 64 fluid ounces.) Direct fired instantaneous water heaters shall be equipped with a thermostatic mixing valve or valves which conform to ASSE 1017-1999. A pressure relief valve shall be installed on or adjacent to the heater. A properly sized temperature and pressure relief valve, based upon the energy input rating of the heater, shall be installed on the tempered line with the temperature sensing element immersed in the tempered water line as close as possible to the mixing valve."


 The Navien with its 2 gallon storage tank would fall under this right?


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## SewerRatz (Apr 25, 2009)

Colgar said:


> That's my understanding as well. Somewhere along the way, I think I was told that the new code clarifies the tankless distinction. I have no idea if that is accurate and I'll believe it when I see it.


 I hope they put in a part about properly sizing a tankless system for the whole home. I get so many people calling me that did "research" on which tankless model they want installed. Many do not realize they unit will only run a couple fixtures at once, if that. I prefer to size a tankless to be able to have all the baths running, along with the dishwasher and clothes washer, and they all will still get the required GPM and pressure.


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## ZL700 (Dec 8, 2009)

SewerRatz said:


> Ok you clarified the first part of the code, what about this part? The Navien with its 2 gallon storage tank would fall under this right?


I'm not aware of any tankless that holds 2 gallons 

The closest to that would be:

The Navien A model with the 2 liter buffer (less than 1/2 gallon) 3/4 gallon approx whole unit

The Eternal, they say its 2 gallon but truly its 1.7 gallons 

So both fall under two gallon storage and according to section 7 of ASME code, in plain term below 2 gallons doesn't suffice as a storage vessel requiring T&P protection.


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## ZL700 (Dec 8, 2009)

SewerRatz said:


> I hope they put in a part about properly sizing a tankless system for the whole home. I get so many people calling me that did "research" on which tankless model they want installed. Many do not realize they unit will only run a couple fixtures at once, if that. I prefer to size a tankless to be able to have all the baths running, along with the dishwasher and clothes washer, and they all will still get the required GPM and pressure.


In all fairness, they then should write a new ammended code dictating the tank size to allow all fixtures to run at once and for how long. Running all fixtures at once and depleting a tank in 2 minutes in my opinion doesnt offer significant tiime to bathe or fill the washer with desired temp.


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## SewerRatz (Apr 25, 2009)

ZL700 said:


> In all fairness, they then should write a new ammended code dictating the tank size to allow all fixtures to run at once and for how long. Running all fixtures at once and depleting a tank in 2 minutes in my opinion doesnt offer significant tiime to bathe or fill the washer with desired temp.


 
I grew up in a two bathroom house, both showers ran at the same time while my mother was doing wash. We never ran out of hot water with a 50 Gal gas heater.

The Illinois code sort of addresses the flow issues in this part of the code:


> *Section 890.1210 Design of a Building Water Distribution System*
> 
> a) Design and Installation. The design and installation of the hot and cold water building distribution systems shall provide a volume of water at the required rates and pressures to ensure the safe, efficient and satisfactory operation of fixtures, fittings, appliances and other connected devices during periods of peak use. No distribution pipe or pipes shall be installed or permitted outside of a building or in an exterior wall unless provisions are made to protect such pipe from freezing, including but not limited to wrap-on insulation or heat tape tracer line or wire.


The issue I have is the fact that when people put in undersized tankless heaters, then call me stating they are having pressure issues with their hot water. When I go there I find that they where taking a shower while someone started doing laundry. I have to teach them how a tankless heater will only flow so much GPM to ensure it gives out the desired temperature. So if they want to be able to run multiple fixtures I told them they need to install a larger unit or multiple tankless units.

I prefer the multiple tankless installs due to when a unit fails they will at least still have some hot water while waiting for parts.


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## ZL700 (Dec 8, 2009)

"I grew up in a two bathroom house, both showers ran at the same time while my mother was doing wash. We never ran out of hot water with a 50 Gal gas heater."

That may be possible because you have approx 38 gallons + recovery of hot water to play with before temp drops. If the washer is 8 gallons, that leaves a estimated 15 minutes of 2.5 gpm mixed temp shower or 2 showers at 7.5 GPM mixed temp, so that is possible 

But your earlier comment included more baths and fixtures (whole house) running which would not cut it with 50 gallons.

Installed undersized tankless is a huge issue. I find to be both the cheap homeowners fault or a uninformed or greedy plumber just as often.


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## Mississippiplum (Sep 30, 2011)

Hell I wish I could do all that with heater I have, but I can't, it's an electric 40, I
Might change it out soon for a larger unit, 


Any way back on the tankless topic, we have to have a dirt leg on tanklesses here, and we can't tie the t&p's together. But atleast they used a data cable to tie the tanklesses together.


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## SewerRatz (Apr 25, 2009)

ZL700 said:


> "I grew up in a two bathroom house, both showers ran at the same time while my mother was doing wash. We never ran out of hot water with a 50 Gal gas heater."
> 
> That may be possible because you have approx 38 gallons + recovery of hot water to play with before temp drops. If the washer is 8 gallons, that leaves a estimated 15 minutes of 2.5 gpm mixed temp shower or 2 showers at 7.5 GPM mixed temp, so that is possible
> 
> ...


Homes with 4 bathrooms around here have two 75 gallon power vent heaters in most cases, the ones where I upgrade them for people I put in a pair of the Bradford White 55 gallon GX-1 heaters. They never run out of hot water. http://www.bradfordwhite.com/images/shared/pdfs/specsheets/119-B.pdf


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## Will (Jun 6, 2010)

plbgbiz said:


> Don't they require the T&P here Will? I never even considered installing a tankless without it. I do see your point though.
> 
> However...If the burner malfunctioned and somehow over heated, a T&P would be nice to have. For instance, is it absolutely IMPOSSIBLE for the burner to come on without proper flow of water? If so, the lack of a T&P valve could be messy.



From Rinnai operation and installation manual.

Safety Features
Overheat: The appliance will automatically shut
down when the appliance exceeds a predetermined
temperature.

Flame Failure: The appliance will automatically
shut down if the burner flame is extinguished.

Power Failure: The appliance will cut off the gas if
it loses electrical power.

Power Surge Fuse: A glass fuse protects against
overcurrent. If the fuse blows then all indicator
lamps will be off.

Fusible Link: In case the overheat feature does
not prevent the temperature from rising then the
fusible link will break shutting off the appliance

The tankless has internal safety features that protect it from high water temperatures. A tankless can only take in so much gas flow to the burner, and can only take in so much water flow(which determines how much gas flow it will need). A Tankless is also equipped with a mixing valve. Tankless has a max tempurature of 120-140 degrees for residential . And with the temperature rise, you won't ever hit that temperature. You also have to manually adjust a dip switch to get the tankless to go over 120 degrees.


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## SewerRatz (Apr 25, 2009)

Will said:


> From Rinnai operation and installation manual.
> 
> Safety Features
> Overheat: The appliance will automatically shut
> ...


Come on Will, you know as well as I do, things can fail. What if the temperature sensor fails and it starts to overheat the water? Not all tankless water heaters have a mixing valves.


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## Will (Jun 6, 2010)

I don't believe you can even get a high enough temperature out of a tankless on a residential unit to pop off a T&P. Most will only do a 45 degree rise on the incoming water. As long as the tap stays open and as long and you incoming water is around 70 degrees you realyy can't get in any danger of getting scolded. 

And as far as I know(I could be wrong) all tankless water heaters mix hot and cold water to get the proper temperature depending on how much GPM is leaving the unit.

I'm not familiar with the Navien unit that has the buffer tank. I know which one your talking about, but I've never installed one. So I don't know much about them.


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## SewerRatz (Apr 25, 2009)

Will said:


> I don't believe you can even get a high enough temperature out of a tankless on a residential unit to pop off a T&P. Most will only do a 45 degree rise on the incoming water. As long as the tap stays open and as long and you incoming water is around 70 degrees you realyy can't get in any danger of getting scolded.
> 
> And as far as I know(I could be wrong) all tankless water heaters mix hot and cold water to get the proper temperature depending on how much GPM is leaving the unit.
> 
> I'm not familiar with the Navien unit that has the buffer tank. I know which one your talking about, but I've never installed one. So I don't know much about them.


The smaller Noritz units do not mix the hot and cold, and Noritz makes it a point in their classes that their larger models do mix hot and cold while other brand heaters do not. What if the mixing valve fails? All tankless heaters will restrict the flow to ensure it is getting the desired set temperature. What if there is a malfunction in the programing, and it is restricting the water flow and over firing which can cause the water temperature reach dangerous temps where a T&P valve would work.

Lots of the Tankless heater systems I work on are set to 180º F So we are awfully close to reaching the temps needed to set off a T&P.

Point is no matter how much the manufactures put some sort of safety built in, it can still fail. Electric tanked heaters have thermostats that supposed to turn off when the desired temperature is reached, if that fails there is an overload/ high temp safety on the thermostat that pops which is resettable, but I have seen this fail as well, and the required T&P valve did its job and opened when the water got too hot. So in this example there are two electrical safeties, and it is still required to have an additional safety. The reason is many know no matter how many built in safety devices things can still fail.

To me it is no big deal to install a T&P valve , a tempering valve, and anything else our code may require.


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## plbgbiz (Aug 27, 2010)

Will said:


> I don't believe you can even get a high enough temperature out of a tankless on a residential unit to pop off a T&P....



Only if the safety mechanisms function properly.

A cigarette lighter flame will boil water if left unattended in a closed pipe.

Granted it may be a one in a million perfect storm, but man made mechanical devices can and do fail. The trick is to put as many devices as possible on a unit so as to decrease the chances of a disaster. A unit with 5 safety widgets is less likely to blow up as compared to a unit with only one.

So...

Adding a T&P valve may not be relevant on 999,999 installs, but if you live in number 1,000,000 then you may be really happy that $10 item was added on.

I guess I can't say with certainty that there is no danger if a T&P is not installed, but I am fairly certain it won't hurt to have it.


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## #1 n the #2 Biz (Sep 22, 2011)

OK, The tankless heaters does not have a temperature and pressure relief valve. It has only a pressure relief valve. The reason that i have been told by rinnai is if the house has a booster pump on the house, or something to that effect. It will relieve the pressure instead of distroying the tankless. The new rinnai tankless comes with "The Isolator" installation kit witch is to be installed completely to insure the warranty. :thumbsup:


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## Mississippiplum (Sep 30, 2011)

In my opinion a tankless should have a t&p, because if the controls inside the tankless were to malfunction and the burner stay running with no water flow through the unit then water temps inside the heat exchange will reach near boiling point and that near boiling water will need to discharge some where or the heat exchanger could explode. and cause some serious damage, now the chances of this are slim but I would rather install a t&p just to be on the safe side.


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## GREENPLUM (Jul 27, 2008)

Tankless heaters dont need a T+P valve, proof of that is the manufacture includes a Pressure Relief Valve with the tankless unit. 

If it helps you sleep better at night install a T+P


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## Will (Jun 6, 2010)

I'm no tankless expert. I should be, I've installed hundreds doing new constuction, but I never repair or service them. 

Is it even possible for the burner to kick on with out flow? The flow sensor is what tells the burner to kick on.


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## SewerRatz (Apr 25, 2009)

GREENPLUM said:


> Tankless heaters dont need a T+P valve, proof of that is the manufacture includes a Pressure Relief Valve with the tankless unit.
> 
> If it helps you sleep better at night install a T+P


The manufacture does not include one. The service valve kit does.



Will said:


> I'm no tankless expert. I should be, I've installed hundreds doing new constuction, but I never repair or service them.
> 
> Is it even possible for the burner to kick on with out flow? The flow sensor is what tells the burner to kick on.


Its a flow sensor, keyword *"sensor"* which can fail, in hopes it fails in the no flow condtion, but what if it fails in the flow condtion. And yes they can fail. I came across a firm on the web that was investgting a tankless explosion due to it turning on with a no flow, and the service kit was never installed so there was no pressure or T&P valve installed. I will try to find it and post it here.


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## Cal (Jun 17, 2008)

Will said:


> I'm no tankless expert. I should be, I've installed hundreds doing new constuction, but I never repair or service them.
> 
> Is it even possible for the burner to kick on with out flow? The flow sensor is what tells the burner to kick on.


 Same way here ,,, installed a bunch ,, but i guess should be ashamed -- Have no desire in servicing them .


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## GREENPLUM (Jul 27, 2008)

SewerRatz said:


> The manufacture does not include one. The service valve kit does..


 
Well, rinnai condensing tankless heaters do come with a service kit that includes a pressure valve. All the service kits for tankless water heater come with a pressure valve only. What does that tell you?


I would also think that thankless water heaters have a "fail safe"? anyone know this for a fact?


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## SewerRatz (Apr 25, 2009)

Just came across two Nortiz units with a code 16, which is water was being overheated. The output water was way hotter than what the controller was set for. The water got upto 200º the controler was set at 150º So the heaters locked out till the problem was able to be fixed. In this case the heaters filters where part way clogged so the flow of water was not as fast as needed for the heater to work properly. 

Now what if the temp sensors did not detect that the water was way hotter than the set temp?


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## Mississippiplum (Sep 30, 2011)

SewerRatz said:


> Just came across two Nortiz units with a code 16, which is water was being overheated. The output water was way hotter than what the controller was set for. The water got upto 200º the controler was set at 150º So the heaters locked out till the problem was able to be fixed. In this case the heaters filters where part way clogged so the flow of water was not as fast as needed for the heater to work properly.
> 
> Now what if the temp sensors did not detect that the water was way hotter than the set temp?


Woah that could have burned someone badly, or caused damage to the unit. That's why we install t&ps on tanklesses incase of a sensor malfunction or in the case mentioned above by sewerratz.


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## c-note (Aug 12, 2011)

we use filteres before cold enters units or the warranty is voided


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## Greenguy (Jan 22, 2011)

Let me ask this when servicing the units do you lift the lever, and dump some water or do you not touch it for fear it may not re-seat properly. 

As to the gas line they may have the drip leg out of the picture, I think our code says it has to be on the last vertical drop before tying into the unit.

Edit: code says "6.13.1 A dirt pocket shall be installed at the bottem of any piping or tubing on the final drop serving an appliance other then:
An illuminating appliance, a range, a clothes dryer, an outdoor grill, a portable appliance or equipment, a decorative appliance, a gas log, a room heater and an appliance incorporating a sediment trap."


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## 504Plumber (Jan 26, 2011)

Greenguy said:


> Let me ask this when servicing the units do you lift the lever, and dump some water or do you not touch it for fear it may not re-seat properly.
> 
> As to the gas line they may have the drip leg out of the picture, I think our code says it has to be on the last vertical drop before tying into the unit.
> 
> ...


turn off the cold and turn on a hot faucet to bleed pressure. There won't be much water left in the unit after that.


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