Energy Spike....

kcopp

I installed 2 electric water heaters in a duplex.... both 50 gallons. One  is a single lady, the other 4 people. The single lady had a bill 7 times higher. Naturally I was freaked out...Pulled and replaced  the elements and the chrome was corroded off the elements. But both elements on the single ladys had continuity... Would that cause the issue?

rlaggren

The billing might be correct...

All it takes is a lot of hot water usage. Long showers, lots of hair washing, full tubs twice a day, doing clothes for friends and relatives, a tub valve that doesn't shut off fully on the hot side....



Or the WH is located in a cold place (ie. somebody left a door open...). Or the WH is normally in a cold place and the old WH had more insulation, maybe a jacket on it.



Or the WH connections got switched for the neighbor's.



Or the hot piping wasn't done quite right and she's supplying one or more of the neighbor's fixtures.



Maybe it would help to put a heat trap loop on the connections _and_ insulate the connections for 3'. It's sometimes a lot easier to do that with the expensive soft insulation that conforms to bends and fittings w/out chopping and cutting.



Did you install or repair a recirc loop that was _not_ operating before?



You don't say whether her bill has always been 7 times higher, but I guess you mean this is new and different. How long has the WH been installed? Was the billing ever "normal"?

rlaggren

Also... Are you sure the billing related to the WH?

I assume you're operating off information the customer gave you about her electric bill.

 

1)  Have you seen the bill? How about last years bill?



2) What else was going on (electrically) during the billing period? Space heaters? Does she use a heat pump and was it chilly out?



3) Other weird stuff, eg.:Felt cold so she left the electric oven on in the kitchen w/the oven door open to make it warmer? Boy friend came over the practiced arc welding in her garage for a month?



Best luck.  Rufus

Ironman

Just curious

Why are you assuming the water heater is the cause?

kcopp

it was a "new " install.

Both water heaters are in the same place. The Landlord did check w/ the utility and they confirmed that there was  a spike. The heat is FHW- BB. She has her own t-stat. The heat is payed for by the LL. The Hot water by the tenant. The water heater is the only thing that changed....

rlaggren

Takes about an hour, maybe some less

To test a WH.



Assuming it performs to spec the usage pretty much has to be either other loads or actual hot water usage. Not sure exactly what you meant by a "new install". When did you replace the heaters or is this a new building? Has the system worked OK previously? For how long? You didn't mention any complain about the hot water supply, so that's been just fine?



Before doing the test, check to see if the T&P relief is working properly. If it is dumping for whatever reason, maybe that is the problem (or pointing to a problem). Some installations put the T&P outlet outside where it's not readily noticed and so possibly the thing was dumping water constantly because of overheating or because the supply pressure was too high; if the pressure goes over 80#, all bets are off - they need a PRV replaced or installed at the water service entrance. Other vague possibilities include one of those "HW purge" pumps installed under a sink somewhere that has failed ON; a mixing valve somewhere w/both hot and cold open (eg a tub/shower valve left on when somebody shut off the flow at the shower head or with a 2nd shower shut-off valve) forming a thermal siphon; generally any other work/changes in the building is suspect.



Anyway:

Open the 'stat covers so you can check voltages or install test lights, make sure things are normal (HW off and hot); test the temp; run tub at moderate flow hot only (too fast and you mix the tank more than you want) into a 5 gal bucket go keep track of volume . It's been 12 years since I did this stuff for a warrantee company - IIRC w/electrics you get the bottom stat "on" after about 1/4 tank and the top stat goes on after about 2/3+ tank; you expect to get about 2/3 of the tank before the water temp drops 10-15 F.



Electrics are more trouble than gas because you really want two clip-on test lamps (with good clips) so you can tell when the 'stats switch and a partner to shout out helps a lot. But basically if you get 2/3 a tank "hot" and the thing is powered up by that time, it's working.



Here is a WH crib giving normal accepted performance standards.

http://www.plumbingshowrooms.com/media/documents/Water%20Heater%20Sizing.pdf





Rufus

kcopp

What I meant by...

new was that they had hot water off a tankless coil before. The old NY AP680  boiler burned through and needed to be replaced. I replaced it w/ a new Smith boiler (cold start) then gave each unit its own electric water heater. (as it was the LL paid for everything Heat & HW. If tenants don't pay for HW they generally will not conserve.) This was early November.

I separated the piping and gave each unit its own heater.

The T&P is fine, this is a no nonsense place no pumps, just 1 bath and a kitchen... they don't even do laundry there. The hot water was a bit cool for them...not even really hot. Pressure is not an issue

rlaggren

Don't take this wrong, but...

Just have to tag the bases. I'm assuming you tested each fixture for each side and found it ran off the correct heater? Especially important if you can't easily see all the plumbing, but should probably do it anyway just to reinforce your sanity (something that works right ).



Other thing is: If the WH is 240volt, have you tested the voltage? It likely wouldn't even be luke warm if that was a problem, but again... sanity. Also check at the element terminals while heating - if there are bad connections somewhere voltage will check OK until the heavy draw, then voltage will drop.



The voltage drop problem also applies to 110volt heaters.



It kinda sounds like _maybe_ the WH isn't delivering hot water the way it should, though. You didn't mention how the neighbor is getting along. Are the 'stats set low?



The other end of the equation is the power... Are the heaters "plugged into" the correct breaker box for each unit? Do the breaker boxes look like they're wired OK? Not my territory here, but maybe both heaters somehow got hooked into your lady customer's load center?



This is one one of those "can't be _that_ many ways.." moments.



Rufus

Larry Weingarten

leak?

If there were a leak in the hot side plumbing, it could show like this.  A pressure test will let you know.



Yours,  Larry



ps.  Sometimes the meter gets read wrong.

Charlie from wmass

I am betting on a crossed pipe

or even a crossed wire. Are you sure they are wired to the right panels and there by meters?

Charlie from wmass

Were you cutting a threading a lot?

If so who's juice was powering all your stuff when you were working. It could be that tenant's meter spins for the power in the basement?

kcopp

not doing much at all...

and it was the other (lower bill) guys meter. I was hardly in the other side of the basement. She showed the bill to the Land lord for the last year. Each month it was $180-190... then it spiked to $700.00!  I changed out the elements Christmas eve....Even if Both sides were using 1 water heater I can't imagine that for a water heater bill. Something was up.... I hope it was the elements, they looked pretty corroded and had some scale on them.

kcopp

No change...

Still a huge electric draw. Looked at at the wiring and it was tight. breaker swapped out. Meter was still drawing crazy HUGE 2000Kw/ mo.... I am 100% sure that the problem is not excessive HW use.

 It is swapped out w/ a new water heater now. Very frustrated! there is no explanation for the huge draw. Would a Bad T-Stat cause this? Hot water is not super hot.... kpc

rlaggren

You might talk with the utility company...

Inform them about the problem, ask for suggestions, help, etc. Feel your way toward a little mutual aid here - they probably would rather not hear about the problem from their customer service dept. if they don't have to - and they will if the problem persists. A lot depends on the local people, the individuals you deal with. I've received some excellent assistance from utilities and other times not. Sometimes it's the bill-payer that needs to call them to get (free) action; if you don't get any good results, the user might be able to.



Possibly they have a way to monitor the house usage by the hour or something. Or they may be able to install a monitor to the WH and see what it adds up to over a week. They may also be able to eyeball the meter and tell whether it's drawing large or not. Then you hit the "on switch" on the WH and see if the draw changes...



Also, multiply out the WH power over 24/7 constant draw, multiply out to the billing period and see where you get vs. the billed/metered-usage. The utility's help desk should be able to do that toot-sweet. See if one water heater running continuously could add up to what they billed for. If not...



One last thought: Have you _felt_ the breaker(s)? Are they warm/hot indicating they're carrying more current than you'd expect? Well, that's just a wild shot. Take care.



Luck.  Rufus