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Smart 40 Indirect Water Heater
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MANUALS (7)
Product Highlights
Description
The Triangle Tube brand has been discontinued by the manufacturer as of 11/3/2025. Suggested replacement units will be available on our website and replacement parts will continue to be available as supplies last. If you'd like any further assistance, please contact our customer service team.
NOTE: The Triangle Tube Smart water Heaters do not come with a T&P Relief Valve, to order a T&P Relief Valve please follow the following link, T&P Relief Valve.
Product Features
- Boiler Output Btu/Hr : 112,000
- 1st Hour Recovery (gal) : 180
- Continuous Flow (gal) : 150
- Peak/Flow (gal/10 min.) : 50
- Diameter : 22"
- Height : 46"
- Boiler Supply/Return : 1"
- Domestic Inlet/Outlet : 3/4"
- Domestic Capacity (gal) : 36
- Heating Water Capacity (gal) : 6
- Shipping Weight (lbs) : 135
Specs
| BTU Input: | 112000 |
|---|---|
| Capacity (Gallons): | 36 |
| Height (Inches): | 46" |
| Application: | Plumbing |
| Diameter (Inches): | 22" |
| Water Connection: | 3/4" |
| Size: | 1" |
| Continuous Draw: | 150 Gallons/Hr @200F |
| Heating Surface: | 16 Sq. ft. |
| Max PSI (Boiler): | 45 psi |
| Max PSI (Domestic): | 150 psi |
Questions?
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Product Reviews
Most Liked Positive Review
Great performance, very minor quibles
Most Liked Negative Review
Outer tank rusted through within 2 yrs
I would buy again
New Tank had Fittings in Different Orientation.
Just what I needed
Nice unit
Water heater works great. Getting it to me was a nightmare
Never buy this tank
Good company, ok tank
Rusted through and leaking
Not full stainless steel
2 Leaked
Product Q&A
14 QuestionsQ: Which part of the product is stainless steel? Several reviews suggest that the outer tank is not stainless, but we were under the impression that it all was.
Asked by Jody 5 years ago
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Verified Reply- SupplyHouseHi Jody! The inner tank is stainless steel and the outer tank is steel. This information is shown on page 4 of the product overview: https://s3.amazonaws.com/s3.supplyhouse.com/manuals/1297270226861/47062_PROD_FILE.pdf
Q: I have a question about this product, I have a Lochinvar indirect tank now with Lochinvar condensing boiler. We are on our 4th indirect tank they seem to last about 2 years then start leaking, so now the factory tells me that I can get another tank, they mentioned the smart tank by triangle tube did they buy Lochinvar so with the issues with the past tanks not sure what to do is there leak issues with Triangle as well thanks for the help.
Asked by Jim 12 years ago
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Verified Reply- SupplyHouse StaffLochinvar was purchased by A.O. Smith a few years ago, and neither company is affiliated with Triangle Tube as far as we know. Triangle Tube SMART indirect water heaters have an internal stainless steel tank that serves as the heat exchanger. Lochinvar may have made this recommendation because stainless steel is a durable material. Lochinvar Squire indirects, however, also have stainless steel heat exchangers, but use a coil rather than an internal tank. It is also possible that you have aggressive water, in which case water treatment could extend the lives of the tanks.
Q: What's the proper T&P relief valve for a Smart 40 tank hooked up to a Triangle Tube Prestige Solo 250 boiler? Manual seems to indicate one (Watts 100XL-8) for the 40 Gal tank, but then another (much pricier) for a 200,000 BTU boiler (Watts 40XL-8). Can anyone answer which to use?
Asked by Jay 13 years ago
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Verified Reply- PexSupply StaffThe Smart40 requires the 100XL-8, which is SKU 0556001. The 40XL is only required for the larger indirect tanks, such as the Smart60 and up. The boiler itself does not effect the choice of T&P valve for the indirect.
Q: I have had a Smart III Indirect water heater in my house since 2005. I just noticed about two weeks ago that I am getting some rusty water coming through my hot water taps in the house. It is more prevalent in some taps than others. I took about 5 gallons out of the tank via the release valve on the side but the water remained rusty colored. Does this mean my tank is shot or is there a fix to this problem?
Asked by Paul 13 years ago
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Sounds like an anode problem. Call a service guy. But, it sounds like a big problem. You can completely drain the tank and start over to see if that works Sent from my iPhone
Q: i am planning to purchase this tank the smart 40 to replace a 40 gal. amtrol tank that is now leaking and the company refuses to honor the life time warrenty. so out goes the amtrol question is is this the tank size i need. and is all i need to do is just take the old one out and replace it with this one or is there other things i need to make this tank work thanks roger
Asked by roger in hot water 14 years ago
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Verified Reply- PexSupply StaffIndirect water heaters are almost always interchangeable. It should not be a problem.
Good morning Roger, I purchased the smart 40 tank over a year ago..It works perfect. Don't know how many members in your family or how big your boiler is. My boiler is 150,000 BTU. It recovers very fast. There're only two of us home now so the water demand is not as great as it would be if you have children and do lots of laundry, baths and dishes. You might want to get the next size larger if you have lots of usage. I'm very happy with mine. Hope this helps. G.
Hi Roger: First off, I should preface this response by letting you know I am not a plumber nor an HVAC expert. I am a homeowner who researched (and ultimately purchased) the indirect Smart 40 a few years ago. There are a lot of indirect tanks on the market but I decided on this tank for a number of reasons. Perhaps you could use these as guidelines when thinking about which type of tank to replace yours with. 1) Warranty: The warranty on the product was impressive. Many of the components are not covered for life but the tank itself is. Some indirect tanks I looked at did not offer this. 2) Capacity and Recovery Time: You should size your new indirect heater based on the demands generated from your household. Simply replacing a 40 gal. with another 40 gal. is not always the preferred measure. You may find (after calculations) that you'll require a smaller or bigger unit. I searched some websites to do a demand/load calculation. It's not difficult to do. Basically, the variables are: the appliances you run along with the number of people in the household as well as the gallons of hot water utilized.. My calculations allowed me to arrive at the Smart 40. The other very important factor is the recovery rate. This refers to its ability to recover and resupply the "spent" domestic hot water. The longer the recovery rate, the more difficult it is to supply out consistent hot water. 3) Head Loss: The better the insulation, the less heat is lost. Most of the heat escapes from the top, hence "head loss". This data is available on all of the brands' specifications sections. This unit comes with its own jacket that provides a good level of thermal retention. 4) Reliability: This tank does not use a coil. The tank in tank design exchanges a greater surface amount of area, making it a preferred choice for me. I also know someone who had an earlier version of this tank and it's still going strong some 18 years later. You should do some homework (it is not a cheap unit) and definitely speak with a qualified plumber/hvac pro before purchasing any model. His/her input, along with your research should land you in a narrow category from which to choose. This is not a do it yourself job and should be installed by a pro-warranty is voided if it's installed improperly. Also make sure you get the residential version of this unit. There is a commercial-grade one if I remember correctly that is not eligible for residential use. An educated choice will pay you back for years to come. Good luck and let me know how you do!
I do not know the mechanicals of the Amtrol. Electricly it should be a drop in. How well the fillings will line up is another story. If you go to the two web sites you might be able to compare them side by side.
I will also preface this response by letting you know I am not a plumber nor an HVAC expert. But I believe the Amtrol tanks have all the plumbing connections out of the bottom of their tank (to minimize heat loss). I'd say they WON'T be easily interchangeable. I'm not saying "can't", just not an easy swapperoo. Have a licensed plumber do it. I do a lot of my own installations, like replacing existing stand-alone heaters, but even I'm considering having a pro put one in my mother's home.
Q: What is the standby loss of this tank (degrees per hour)?
Asked by Crown Guy 14 years ago
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According to http://blog.triangletube.com/blog/hydronic-heating-solutions/water-heater-co mparisons-indirect-water-heaters-and-instantaneous-water-heaters, 1/2 degree F per hour. <http://www.triangletube.com/documents/2/SMART> -=Stephen=-
Per the manufacturers documentation this tank has a standby loss of less than 1 degree per hour. I have not personally verified this but I am very happy with this tank.
Hello, Triangle Tube says the following on their website: SMART Series, is insulated with 2" of injected polyurethane foam, resulting in a stand by heat loss of less than 1º/Hr. I hope this helps.
Good question. I asked the same thing as it is stated as loosing 1degree/hour but when I installed it; and monitored its internal temp from my Triangle Tube boiler, it was closer to 2 degrees/hour. I could simply be a matter that the sensors and electronics here are not as accurate as their lab stuff thus giving erroneous readings. My question then is what is the standby loss for the average, good, plain old tank? Martin Loney CTS-D Duocom Canada
I have not measured the temp. Loss per hour. But I can tell you that I have saved a ton of $$ on heating oil. I'd say my boiler only fires once or twice a day to keep the water hot.
Q: what is the energy factor/thermal efficiency for the smart 40 water heater
Asked by 14 years ago
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Verified Reply- PexSupply StaffIndirect water heaters do not have these ratings. They are essentially just tanks and the efficiency at which they operate is dependent on the efficiency of the boiler that actually heats the water.
Indirect operate at approximatly 92% of the boiler afue. Multiply the AFUE by .92 for an approximation of the EF.
Q: I am trying to correctly size this unit for installation for a family of 5. Currently have a Peerless WBV-03 boiler with an estimated output of 100,000. Is this boiler adequate to get the required recovery for this unit or should I be looking at a different unit.
Asked by cleaver97 15 years ago
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Verified Reply- PexSupply StaffOn average a family of five will use about 100 - 150 gallons of water during a peak hour. This unit should cover that demand.
Q: I am trying to hook up the smart 40 water heater to a white rodgers 3 wire zone valve. What terminals connect to make this operate correctly. The smart 40 has the terminals c, 1, & 2 while the white rodgers zone valve has 2, 2/5, 4, 6, 1, & 3. Thanks for your help.
Asked by brrrrian 15 years ago
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Verified Reply- PexSupply StaffYou will need to use a zone valve controller. The zone valves themselves do not wire directly to the indirect water heater.
Q: Can any of the Smart Indirect Water Heaters be installed on its side, assuming the use of a platform that provide stable support?
Asked by 15 years ago
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Verified Reply- PexSupply StaffNo, this is not recommended.