Water heater recommendations

[stampedecarwash]

Hello
Our water heater failed today. It is A O Smith 100 Gallon 199,000 BTU. If I want to replcae it with exact same one its very expensive. The On Demand tankless heaters are alot cheaper. Do you recommend on demand for a carwash? I have a Coleman Hanna Super Savor system which hot water goes from the heater to a tank before it goes to the pumps. That makes me wonder why not using on demand since there will always be water in the tank. So Im never tankless. Thoughts?

 

[Toms PTcarwash]

You need to be sure the tankless you choose can flow the gpm you need to keep up with your demand.
Usually tankless are more expensive than a tank for a given gpm flow.

 

[stampedecarwash]

Thanks only my soap and wax are hot, plus with hot water goes and sits in the tank before feeds to the pump, I never provide a super hot soap/wax to customers anyway… how do I measure what my gallon per min is? I have 5 wand wash each with a CAT 5CP2120W pump which each is 4gpm. So if all my 5 bays using soap/was then I need a heater than can do 20 gpm?

this is the spec of the heater just failed. Isnt this 4 gpm? 227 gph?

 

[MEP001]

For a MUCH lower cost than your unit that failed, you can run a tankless heater circulated through a storage tank. I need to do this at my wash, but before I do I plan to switch wax to low- or medium-pressure to reduce the hot water consumption.

 

[Earl Weiss]

Do you need to run straight Hot water to the bay? I have Cold and Hot T'd together so I can adjust temp to warmer during cold weather and not as hot in Hot weather so that reduces the Hot water flow as opposed to only Hot feeding any function.

 

[stampedecarwash]

For a MUCH lower cost than your unit that failed, you can run a tankless heater circulated through a storage tank. I need to do this at my wash, but before I do I plan to switch wax to low- or medium-pressure to reduce the hot water consumption.

Thanks is Rinnai CHS 199 100 HIN, a tankless heater with circulating tank? Here is the link to it:

CHS199100HiN | Rinnai

CHS199100HiN - Commercial Water Heating - Demand Duo™ H-Series Hybrid Water Heating System Indoor, Natural Gas, 199,000 BTU, 119 Gallon

www.rinnai.us

 

[MEP001]

You can get a heater and tank plus a circulator pump for under $3,000. A simple hookup would be to use a tank mounted thermostat to turn the pump on, which will trigger the heater to run and heat the water in the tank.

The one you linked is over $8,000.

 

[stampedecarwash]

Exactly that $8k USD changes to $12k CAD when it makes it to Canada. These Rinnai ones seem to be a combination of both on-demand heater attached to a circulating tank as you described above.

 

[Randy]

When you say your A.O Smith 199,000 btu water heater failed, what do you mean failed? Is it leaking or it wouldn't make hot water. At hot water appliance rated at over 199,000 btu is classified as a boiler. Shop around we got a couple of 199,000 btu water heaters for $1000 each that the outer jackets were dented in shipping, nothing wrong with the tanks.

 

[stampedecarwash]

When you say your A.O Smith 199,000 btu water heater failed, what do you mean failed? Is it leaking or it wouldn't make hot water. At hot water appliance rated at over 199,000 btu is classified as a boiler. Shop around we got a couple of 199,000 btu water heaters for $1000 each that the outer jackets were dented in shipping, nothing wrong with the tanks.

Water has got to the flame chamber. So things are rusted inside it to the extend water has made its way to the fire chamber. Here is a pic. Thanks for the tip Ill look around.

 

[SCWSMatt]

This is not a cheap problem to have that's for sure. I've been back and forth between on demand or boiler. I def recommend on demand with a tank. Otherwise your just throwing money away for nothing. My shortest tunnel requires 3 on demand just to produce luke warm water.

I would love to hear about a 3k solution because i was just quoted 11k for 2 on demand with tank, or go 960k btu boiler for 22k

 

[Randy]

Do you really need 100 gallon 199,000 btu water heater? What all are you using the hot water heater for? Could you use a 98 gallon 74,000 btu water heater, something like this https://www.lowes.com/pd/A-O-Smith-...r-Limited-Natural-Gas-Water-Heater/1000213663

 

[Toms PTcarwash]

Guys, you really need to be sure of a couple things.
The 199k water or the 99k water heater, or any "tank type" water heater for that matter is made to sit at a temp of 120 or greater. When they see lower temps with a high demand they start to condense water and "rain" in the combustion chamber and on to the burner. This really shortens the life.
Commercial tankless such as Takagi, and Rinnai are designed to handle this condensation if properly installed. Copper fin tube boilers can also handle it to some degree, but need a "primary / secondary loop and storage tank.

The next thing is max water flow, and head loss.
Without going into a bunch of engineering calculations, common sense says if you have a 2" water main and you pipe it to a water heater with a 1" inlet and outlet, its going to be a problem.

Go to a local commercial plumbing or hvac distributor. They will have someone that can help you with these calculations and provide the proper equipment.

Box stores do not have what you need for a busy carwash, unless its for the hot water in your restroom.

The lowest price is almost always not the best solution!!!

 

[Greg Pack]

I am about to replace a raypack 275K btu boiler with recirculating storage tank with a Rheem 100 gallon 199K btu water heater. The boiler is fine, I just need the floor space. An on demand mounted on the wall tied into an existing tank that MEP mentioned would have been a more economical solution. The water heater I bought is simple. I've used these in the past and really haven't noticed an issue with them and have one over 20years old, although it is also going to be replaced soon My gas bill is relatively low now (probably an average of $200/Month) and I saw no reasonable return on investment on the expensive high efficiency units. Best price I found was zoro with a 20% off coupon and i think it cost a little less than 4K delivered.

 

[Toms PTcarwash]

Greg, if you always keep that storage tank above 120 degrees, you should be good. If not you will trash that water heater in a couple years. If you look at the pic a few posts above, that is what happens when condensation occurs in the heat exchanger.

 

[bigjws]

I’ve always figured when I have to replace my boiler I’d probably go with the option that 2biz has… That HTP commercial tank… You’ll have to search for it on this site, but it always looked pretty good to me

 

[Toms PTcarwash]

I bought my carwash about 18 years ago. I was just two years old and was designed and equipped by a carwash supplier that is still in business today. Something something systems.
I was brought in by the original owner as some problems could not be solved by the designer / installer.
A 1,000,000 btu copper fin tube boiler was installed with a 150 gallon storage tank. Yep, it heated the water fast. It would fire up for 1 to 2 minutes and shut off, all day every day. And it would rain on the burner due to short cycling.
A couple quick calculations told me this was about 70% oversized for even the most possible loads. We pulled the boiler, replaced it with two Tagkai 250 btu units with a staging control piped into the storage tank with a secondary recirculating pump to keep the flow needed for the Tagaki's. Only in the middle of winter, with all five bays and the auto wash cranking away does the second boiler fire up.
Gas use dropped 20%. Maintenance dropped 100%

 

[2Biz]

I'll have to disagree with some of the statements here...Not ALL HE tank style heaters are the same...Some of the HE designs use "Lined Steel" tanks and can corrode/rust over time. The HTP is an HE design that uses an all stainless steel tank and SS heat chamber. It is designed to condense and drains the condensate from the heater without damage. I think it has 5 stages of modulation and have rarely heard it shift out of low gear. It can be set as low as 100° and is where I have mine set. Its now 7 years old and has been flawless....Only issue, actually not much of an issue, is the control errored out once...I believe I had a power failure while it was running that caused the fault. A simple restart fixed it... This heater is a beast....My most busy day for my 4 bay (Warm Winter day after a major snow) I used 4400 gallons of water, not all heated water of course, it kept up fine without running out of heated water. I heat soap and wax cycles.

As for the demand heater, circulator, and storage tank, I batted the two methods back and forth for a really long time before settling on the HTP...The HTP is all SS, takes up a lot less space, less parts to maintain, and has flow capabilities with 1" ports to 40+ gallons a minute... Yea, it won't heat that much continuously (But it doesn't have to), and it won't starve a pump either in comparison to operators who think they can heat water with a demand directly to the pump stand...The HTP is more expensive, but so far I feel I've made the better decision between the two methods....

 

[Greg Pack]

2biz, sounds like a good solution, what as your total price for the system?

 

[soapy]

I use 2 Voyager units that were Pre HTP designation. One per location. Basically the same unit. 199K BTU with 80 gallon tanks. It will raise the water temp 5 degrees per minute. I run two IBAs and a 4 SS bay wash with them and always have hot water. They even have a built in heat exchanger that you could hook into for floor heat if you wanted. One unit has been in for 23 years and one for 13 years and have had very little problems with either.