Advice for replacing broken water heater

branimal

My 75 gallon natural gas American Water heater was leaking from the bottom this morning. I shut off the gas, drained it, and removed it from the boiler room. It was 12 years old. I replaced the anode rod maybe 3 years ago.

I'm gut renovating my 3-family building right now, so I can rework the plumbing to have each apartment pay for it's own hot water. The broken 75 gallon water heater was serving all 3 apartments.

There is a 1 1/4" gas line that runs into the boiler room and supplies a fairly new ~180K Burnham (2018) steam radiator system. That line tees off to 3/4" pipe that was providing gas to the 75 gal water heater. This gas line doesn't supply gas to any of the apartments. So I will have to pay that bill.

I'm thinking about running three electric hot water heaters for each apartment. There is enough room in each apartment's electrical panel for a 2-pole breaker. Electrical panels are in the basement not far from the boiler room.

Based on this, I think I could install 3 electric water heaters. There is enough space for 3 water heaters down there.

Each apartment will have 3 tenants. Each apartment has 2 bathrooms, a washing machine and a dishwasher. Will a 40 or 50 gallon water heater suffice?

There are no incentives/rebates for electric water heaters in NYC right now. But the heaters are not very expensive $530 - $560 / per unit.

Any thoughts or advise on this plan?

Jamie Hall

This would certainly be good from the standpoint of letting each apartment pay for its own hot water (I assume the plumbing lends itself to that?). I would say, though, that you should certainly go for the 50 gallon heaters.

Larry Weingarten

Hi, I'd also look into 120 volt heat pump heaters, at fifty gallons. The bigger size helps make up for the slower recovery. Also, that approach shouldn't tax the main breaker panel.

Yours, Larry

ethicalpaul

Do your leases indicate who pays for hot water?

Curious: What was the condition of the anode rod you replaced?

WMno57

If later an apartment complains about not enough hot water, you could raise the temperature on their heater and install a mixing valve to get it back to 120.

branimal

ethicalpaul said:

Do your leases indicate who pays for hot water?

Curious: What was the condition of the anode rod you replaced?

Hi Paul,
The leases will indicate that the tenants will pay for the hot water. Here in NYC we are only required to provide cold water for free.

The anode rod was completely shot when I replaced it 3 years ago. I'll take a look at the one I put in when I get a chance.

JUGHNE

While I am not against heat pump water heaters, I would not put those in a tenants building.

ROI?? Where is the Return on your Investment?

Most tenants will not care about the "green" hot water, they will only care to not run out.

Then if any breakdown you have to be Johnny on the spot with the replacement.

I would go for 3 50 gal plain jane electric tanks.
I would even consider buying a spare and leave in the box in the basement.

How many amps are each panel rated for?

branimal

JUGHNE said:

How many amps are each panel rated for?

I think 100 or 125amp. Each apartment has a main panel in the basement and I installed sub-panels in each unit. Modern NEC code requires so many circuits.

branimal

Jamie Hall said:

This would certainly be good from the standpoint of letting each apartment pay for its own hot water (I assume the plumbing lends itself to that?). I would say, though, that you should certainly go for the 50 gallon heaters.

Yeah the plumbing shouldn't be too bad. Currently there is one 3/4" hot water riser that tee's off on each floor. B/c I'm renovating, I have access to that plumbing stack.

JUGHNE

Electric range, dryer & AC?

Hot_water_fan

Seems simple enough to go the 3 electric heater route. If the panels are tight, you can get them with smaller elements than the typical 4.5kw. 

branimal

JUGHNE said:

Electric range, dryer & AC?

3rd floor - gas dryer and gas range.
2nd floor - electric dryer and electric range
1st floor - not sure yet

Plan is to install mini splits on each floor.

Jamie Hall

You're kind of pushing it with 100 amp service, but it should work with the electric range and dryer

hot_rod

If the water heaters are in the same room as the steam boiler and the space is large enough, I would look into HP water heaters
There are some pretty hefty rebate programs available to help off set costs

There are versions that  need dedicated 240v circuits all the way down  to models that can share a 120v circuit. So you should have adequate power

EBEBRATT-Ed

Electric Dryer stove and water heater will go in a 100 amp panel without AC for sure.

JUGHNE

In the late 60's we changed out a lot of house services from 60 amp fuse box to a fine 100 AMP FPE panel...no nuisance trips of CB's.....guaranteed.

The house was about maybe 1200 sq feet and got a 2-3 ton AC added to existing furnace.
It had electric range, dryer and probably NG water heater.

However IIRC we did 100amp for houses that had ele WH in addition to range and dryer and AC.
125 amp svc no problem and you also have the diversity usage of loads.

branimal

I agree 100amp is pushing it.

I looked at the panels - it can handle 125 amp. There is a 100 amp circuit breaker in there. But I can replace it with a 125amp. It's an old GE Powermark plus panel.

I ballparked the AMP usage for the 4 major appliances. I'm not sure if the 80% circuit breaker rule is still applicable. All my wiring is up to spec. (6 gauge for the range, 10 gauge for the dryer). I might be off on my amp usage.

This is assuming everything is running at the same time. Which is possible. Then if someone is using a high wattage hair styling tool (blow dryer, straightener, curler, etc) it could get close.

Jamie Hall

Doesn't leave you much, does it? One toaster... toaster oven... hair dryer... and you're done. Wire sizing goes by the 80% rule; breakers don't.

Many electric utilities also have a main service breaker outside the building, near the meter. You need to look at that one, too -- and that is not yours to touch. That's the power company's property.

Hot_water_fan

@branimal google panel sizing. There’s a right way to do it out there, it’s not just adding everything up. 

How big are these apartments? The mini split and DHW amps could both come down 

bburd

The limit on maximum capacity here is not just the size of the panel and its ability to accept a larger main breaker, but the size of the feeder and/or service cables. 

mattmia2

You have to do the load calculations on each individual service and the conductors to it and on the conductors for the service for the whole building if those conductors are shared between all the individual services. Just having an open space doesn't tell you if it can handle the load. There is a procedure in the code to calculate the load on a service.

Electric water heaters have very slow recovery, the tank needs to store enough water for nearly the entire draw. Raising the temp doesn't get you a lot more capacity. Depending on how the tenants use hot water a 50 gallon could be far too small with 2 baths and laundry.

I thought a $150 water heater was inexpensive. I think they are all very expensive now after the price of steel shot up 15 or so years ago.

branimal

I called the water heater company to see if the item was still under warranty. Turns out the warranty expires in February 2024 (12 year warranty). It's a 75 gallon Nat gas WH. They offered me $350 - that was the "calculated remaining value of the WH". I was shocked. Pretty good customer service.

jesmed1

branimal said:

I called the water heater company to see if the item was still under warranty. Turns out the warranty expires in February 2024 (12 year warranty). It's a 75 gallon Nat gas WH. They offered me $350 - that was the "calculated remaining value of the WH". I was shocked. Pretty good customer service.

@branimal Just curious, you mentioned you had replaced the anode rod. How many new anode rods did it get over its lifetime? Just that one, or more?

The reason I ask is that we also have a 75-gal natural gas water heater. It was installed in 2013 with dual anode rods and a 10-yr warranty. I replaced one anode rod in 2020 and again in 2022. When I saw how fast the magnesium anode rods I was installing were being eaten, I then installed a Corro Protec powered anode rod so I wouldn't have to keep installing magnesium rods once a year.

I'm curious how long our heater will last, given that I didn't start replacing anode rods until year 7, by which time the original rods were probably long gone.

branimal

jesmed1 said:

branimal said:

I called the water heater company to see if the item was still under warranty. Turns out the warranty expires in February 2024 (12 year warranty). It's a 75 gallon Nat gas WH. They offered me $350 - that was the "calculated remaining value of the WH". I was shocked. Pretty good customer service.

@branimal Just curious, you mentioned you had replaced the anode rod. How many new anode rods did it get over its lifetime? Just that one, or more?

I only replaced the anode rod once ($50 flexible anode rod from HD). I bought the home with the WH in place. I doubt the prior owner replaced the anode rod.

branimal

I did a simple load calculation with all the major appliances I could think of. While it's unlikely all these these items are running simultaneously, it is possible. This would put me over the 80% threshold.

I will run my dryer and cooking range on natural gas and that will safely get me under the limit.

Service line - FWIR I have #3 incoming service cables, which should allow 125amps.

mattmia2

There is a procedure in the code. It has allowances for the square footage of the dwelling, specific required outlets like laundry and kitchen outlets, and procedures to calculate the load for various fixed appliances.

If the service to each individual apartment are served by a common feeder then the load on those conductors also needs to be calculated.

Hot_water_fan

A 3 ton heat pump for an apartment? How big are these? 

branimal

Hot_water_fan said:

A 3 ton heat pump for an apartment? How big are these? 

Its a 1000 sq ft apartment with 3 bedrooms and one large living space - so 4 indoor units. Three 9k and one 12k. 10' ceilings. The bedroom units might be a bit oversized but it was the smallest Senville offered.

JUGHNE

IIRC, Mitsubishi has 6K indoor heads.