Commercial electric hot water heater
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An organization I’m involved with is doing a major remodel of a space, and part of the plans is for new kitchens (two and for good reasons but not important here).
Part of the plans, as cost cutting measures intrude, is to install a 100 gallon electric hot water heater. Since my department will need to carry the cost of repairs and replacement in the future, I hit the roof – they even want to take out the Natural gas piping since both kitchens will be all electric. Electricity rates here are among the lowest in North America, by the way, but so far, so is gas.
My usual plumbing sub told me the group is nuts. The cost to install is about the same as with gas, but running costs and replacement/repair of the elements and future tank renewal are expensive. I’m also concerned about speed of heat recovery in a commercial kitchen.
Could I please get some other expert opinions?
Quality repairs for your home.
AaronR Construction
Vancouver, Canada
Replies
Sorry to rain on the parade, but given the choice between gas and electic, in BC, Canada, I've always thought that electric had a better ROI. (Currently $.0605 CDN per KWH)
>>>The cost to install is about the same as with gas, but running costs and replacement/repair of the elements and future tank renewal are expensive.
In my experience gas tanks cost way more to install; i.e. black pipe and venting requirements VS some feet of #10 NMD. In your case does this offset the cost of elements and tank renewal?
>>>I'm also concerned about speed of heat recovery in a commercial kitchen.
That may be a valid concern.
>>>Could I please get some other expert opinions?
Disclaimer: I'm no expert.
I agree that I wouldn't go so far as to tear out pipes....
Scott.
Edited 8/12/2009 1:34 am by Scott
Thanks for the quick reply.
Venting is already part of the plan for range hoods etc.
The trend here is to toss electric, not gas, tanks for the heat recovery issue alone. If I could a case for the tankless systems, I would.Quality repairs for your home.
AaronR ConstructionVancouver, Canada
"Venting is already part of the plan for range hoods etc."Both those have to be completely different systems.Recovery is a problem and usually handled by a larger tank. However, I have absolutely no idea what the usage patterns that the kitchen needs. More storage might not help in some cases.And I have no idea of why the replacement/repair expenses would be higher for electric.Yes the elements might need replacements, but that is not a large expense. And much less than trying to replace a burner.And the tank should last as long if not longer. Much less stress on the tank keeping it in a moderate tempature range with and internal heat source than trying to heat it with hot flames from the outside..
William the Geezer, the sequel to Billy the Kid - Shoe
But you can't build a case for tankless. Or you shouldn't try. Tankless in your application would not be a good choice. Power outage? No hot water. No particular energy benefit, either; particularly if the kitchens are used often/regularly. Talk about expensive to install to boot!!
The arguments for gas/electric seem fine. Pay your money, take your choice. As a rule, electric will become WAY more costly to operate than gas. Historically electric prices have always been 2-3 times the cost of gas (for usable Btu). Your kitchen should be all gas. Most cooks like a gas cooktop anyway. Give me your cost for each and I'll compare them for you if you like.
While IMO, the electric is cheaper to install, it may not be the best long term value. But I know less about e.g. longevity of one tank over the other. I'm more of an energy guy.
I agree with Bill. Electric should last longer and elements ain't that expensive. Out here in Sask, 3 to 5 years for commercial gas seems to be normal.
Want another option? Use 50 gal gas as a preheater, connected to the 100 electric in series with bypass valves and a small recirc pump on a timer. The 50 will do most of the work and the electric will kick in during high demand. Plus with 2 heaters, one starts to leak, isolate it and keep cooking.
"100 gal" and "commercial" in the same sentence brings up a real issue: is this a 'water heater,' or a 'boiler?'
Code issues greatly multiply if it's a 'boiler.' After that, give them what they specify. After all, change orders can be profitable.
In my experience, electric water heaters have a longer lifespan than gas units. (Our electric is almost 33 years old.) The heat exchanger in a gas unit is its weak link.
If you are concerned about recovery with electric you could look for a water heater with more wattage at the element.
I'm not sure how much variation there is in elements. But it's worth a look.
Will Rogers
First I'd check codes... here anything 80gal or larger is a "boiler" requires different permit and yearly inspections... but might be fine where you are... but the cost for a single 100gal... is stupid compared to a 75gal which could feed the high use stuff... dish/pot washing ect... then install a cheaper 30gal to feed your handsinks... restrooms ect...
Now... question... gas vs electric... I would guess a 100gal electric would require at least 100amp service maybe 200amp if it was a fast recovery... that alot of copper wire and would spin a meter like an arc welder... do you have that much extra service? to wire that puppy in could double the cost... black pipe is cheap vs copper wire and building a service...
I have built alot of commercial kitchens and except for the military have never used electric for cooking... (military always has gen sets)so they have a reason...
I'd look at the 75gal be'n gas... and the 30gal be'n electric...
just my off the cuff think'n
p
I didn't think size determined boiler vs heater. Although I'm not certain where the line is drawn. 100 gallons is not that large of a water heater in a commercial application. It is only a little large for residential. Someone else mentioned the boiler thing, too. I know boilers may have a higher pressure rating required ... but again ... what says something is a boiler vs. a water heater ... maybe someone will enlighten us.
The ASME "Boiler and Pressure vessel" code defines 'boiler' by the btu output of the heating elements.
Commercial is the defining term around here.
We have one building with a 40 gal. domestic WH and two heating boilers. On the same property our main building has domestic hot water boiler. All of them are inspected annually by both the local authority and the insurance underwriter.
Local codes rule.
Knowone has ask about the electric service?
We have a facility with four 100 ga. WH. I can't recall if they are parallel or series piping but do recall that there is a circulating pump and loop. IIRCC they are 480v heaters. Even with our hard water we have inly replaced two of the four tanks in the last 15 years for leaking tanks. Replacing heating elements is simple and the cost is minor.
The HWH banks serve two locker room/ showers for our linemen and gas crews.
I would think that the cost of running electrical services to the water heater, as well as to the stoves, would speak in favor of gas. Besides, electric cooktops are miserable to cook on and I've never seen a commercial kitchen have anything but gas. It would be terrible to have gas available and rip it out for no good reason.
Ah, my boy, you have never seen a remodel insituted by lawyers and accountants, with the architect now the project manager, and at the end of realizing it's going to cost more than budgeted, decide to go ALL ELECTRIC to save $30000.00 an a 2 mil job.
According to the chair of the committee (I was excluded), a professional caterer was brought in as consultant and agreed electric was fine.
Sigh. Since I'm a professional renovator, my input was not sought, although I'm on the Board .........Quality repairs for your home.
AaronR ConstructionVancouver, Canada
OMG - lawyers and accountants!?!? $30K on a $2mil job is only 1.5%! Have you really determined that gas vs. elect will cost $30K more to install (total installed cost)? What a place to cut corners! I'll bet their finish work didn't cut corners or consider e.g. sustainability (I can't believe I just said that). What kind of heating/cooling did they use? Baseboard heaters and window shaker A/C? I suppose they cut corners on the range hoods, too. And managed by an architect (who knows little about the technical issues, I'm guessing). And they paid a professional caterer to say their idea was OK ... I'm guessing not an independent person or one who was not well experienced.
Again, another good example of people making decisions about technology w/out the benefit of understanding the science and the practical implications of their decisions. You'd think 'smart' people like lawyers and accountants would look past the end of their nose before making a decision.
Got no money to build it right, but they have the money to pay the energy bills down the road. I'll bet they complain about the cooking, too when the cooks are stuck w/ electric ranges.
I feel your pain. The old expression pertains, some people know the cost of everything and the value of nothing.
As long as you get paid, that's probably the best you can do. Stay cheerful. You are fortunate to have a job.
Sigh. Since I'm a professional renovator, my input was not sought, although I'm on the
Just reread that.
ROF
I've been telling my supervisors how to fix a drainage problem at the back of building for five years.
Had 6" of rain in < 60 minutes three weeks ago. Storm sewers couldn't handle it, and our "drainage problem" became a big issue after it flooded part of the first floor of the building.
Called in an engineer.
Paid him $300/hr to tell them how to fix it.
Same solution they had been getting from me.
Funny how thier hearing improved when it cost $300/hr.
They hired me 24 years ago because I was a commercial construction superindentent.
Now I'm just a dumb old "union guy."
LMAO
Aaron, unless it is too late, check the recovery of the electric vs a smaller gas unit. Gas might be cheaper. Both kitchens going at the same time? Any one know the actual load? Most restraunts around here only have a 75 gal heater.
Another option is low temp dishwashers, probably get one free if you commit to purchasing chemical.