New Homeowner Question about Water Heater

3 years ago

My girlfriend and I will be moving into a two bed, 1.5 bath townhouse at the end of this month. The inspector pointed out that the condo, which has electric heat throughout, has an 80-gallon electric water heater for the unit. He said it looked original with the house (1984) and was stone-walled, so he said because of that, they last much longer than the modern ones which have a shorter lifespan. He did suggest that we could upgrade to a modern one to save money on our electric bill since it’s just the two of us, but other people that are handy are telling us to keep it since it is more durable and will hypothetically last longer.

My question is, would it be worth it to upgrade to a more modern electric water heater, maybe 40-50 gallons, so as to reduce cost of electric bill and risk paying for repairs or replacement if modern one breaks, or should we keep the older,more durable one? Thanks for the insight and suggestions!

Featured Answer

kudzu9

3 years ago

I agree that replacing it isn't a bad idea if it is really 36 years old. However, it sounds like you think that the size of the water heater is directly related to the cost to operate it, which is a misperception. The cost is mainly a function of how much hot water you use: whether a gallon of hot water comes from a 40-gallon heater or a 100-gallon heater, the cost to heat the water is the same. The only difference is that maintaining the heated water at the desired temperature in a larger tank costs a little more than maintaining the temperature in a smaller one. However, given how highly insulated modern water heaters are, the amount of standy loss is pretty small regardless of the size of the tank. So, bottomline: consider replacing the tank in the near future, get one that is very well insulated, and choose a size that you are sure will be adequate for your needs (like two showers in quick succession) without worrying that an 80-gallon heater will cost any significant amount more to operate than will a 40-gallon heater.

Sort by:Oldest

Comments (7)

jrb451
3 years ago
Thirty-six years is really old for a HW heater. Eighty gallons is way big for 2 people. How inconvenienced would you be to go without hot water for 2+ days while you get a replacement. Would anything in the room with the water heater be damaged if it suffered a massive leak? You feel lucky?
dadoes
3 years ago
Is there a whirlpool tub or multi-head shower that calls for extra hot water capacity? Date or serial number on the unit to confirm the age?
Related Discussions
Help for new homeowner - furnace/water heater/AC
Q
Comments (9)
What you are describing is called the rule of thumb for HVAC sizing. It is the wrong way to do it and results in systems that are over sized. It is a form of guessing in my opinion. This is the way HVAC contractors who are lazy and can't be bothered to spend the time to calculate the requirements of your house. Over sized systems cost more to install, are inefficient, noisy, uncomfortable, and die prematurely. The only positive is they are more profitable for the HVAC contractor. I would not install a humidifier unless I really needed it. Are you currently having low humidity problems? Low humidity is usually a sign of leaking windows and doors. The steam humidifiers are supposed to be the best.
...See More
question on venting water heater (orphaned water heater)
Q
Comments (1)
Mechanical Codes require flues or chimney to be resized if appliances are removed and some appliances are left 'orphaned'. It is likely that your home inspector uncovered a Code violation and unsafe condition because of this 'orphaned' water heater. The simplest means to correct the problem is usually to replace the water heater with a new one and have that new water heater direct vented or power vented to the exterior. This should be done at the current owner's expense. Contact your local mechanical code inspector for details.
...See More
Questions about Rinnai Tankless Water Heater
Q
Comments (11)
Mounting the remote outside makes absolutely no sense. The purpose of the "remote" is to allow changing the temp setting at one (or more if there are multiple remotes) of the hot water usage locations inside the house. I typically see them mounted in the master bathroom. Tankless water heaters operate at best efficiency when the setpoint is AT the desired hot water temperature for a given task and only the hot water tap is run, for showering for example. I don't have a remote but my tankless is in a broom closet in my laundry room adjacent to the kitchen so is easily accessible for adjustment. I keep it set at 103°F as the normal temp (for showering) and raise it temporarily for other tasks such as handwashing dishes or laundry. Most people run a higher setpoint for "normal" use and perhaps would lower it for showering, thus having the remote in their bathroom.
...See More
Urgent question about water heater.
Q
Comments (22)
mandy has the right idea, you should be able to figure out yourself, or your plumber can help to check. Personally I'd be surprised if the smaller model wasn't sufficient. I think the way to understand it is this: the water heater's size determines how quickly you can replenish the storage tank (or recover from all the water being used), and - at the margin - continuously heat. The storage tank's size drives how much hot water you can use in a short period before running out. Bottom line is basically, how many of your seven people take a shower in a short period of time? Does everyone expect to have a shower within a single hour in the morning? On paper, your 120 gallon tank would cover 4-5 standard showers, likely less than that in practice with other needs (handwashing, kitchen usage, etc). The 50k BTU heater should have a figure for recovery in gallons per hour - perhaps something like 50. That's basically its maximum output. It would then take two or three hours to heat up your large storage tank (whereas your current 200k unit would fully recover in an hour). The hot water heater itself will have storage (50 gallons?) to include in your calcs. It sounds like your current set-up is more or less sized to be able to meet maximum likely demand at all times, with no significant recovery period - i.e. it might be able to meet all demand without the storage tank just by running the heater. Of course, keep in mind there are losses in the system and the real world 'hot water at the tap' will be somewhat lower. So you should be able to figure out how to test this. But fairly simple logic test - if everyone takes showers at different times of day, likely no problem. Even spread out over 2-3 hours you may be fine. If everyone takes two extra-long showers a day and all within the same time periods, maybe not. A few additional thoughts: -Of course, keep in mind laundry and dishwashing needs. But also check if they even use household hot water - mine do not, they heat water internally. (Then considerations of when you run them, of course). -Have the plumber check the storage tank - it'd be a shame if it started having problems right after, and they're likely the same age. Also note, assuming this is gas-fired, it's not a bad thing to have a smaller one running for longer periods. (I'm also a bit surprised there are only two sizes available - surely there are in-between sizes available, like 75k or 100k BTU?) I'm in a seven person household, too - and in my experience it's rare that everyone takes showers within short periods. I can't compare my set-up (household heat and hot water from same boiler), but on paper I wouldn't think the extra expense worth it, just based on our actual usage. Of course, if you're the last person to shower after everyone else and you can't stand even once running out, you might think differently.
...See More
kevin9408
3 years ago
last modified: 3 years ago
I really don't see how replacing your hot water heater will save you money. there is no magic process to increase the efficiency of resistance heating and it is already 100% efficient with any losses related to standing loss of about 1/2 degree per hour and stone lined WH's could easily last 50 yrs so what's the hurry? I suggest buying a water heater insulation blanket for the WH to reduce standing loss to less than a degree per day giving you about a 99.6% efficiency value, and wait until the thing leaks or the element burns out. Replacing it isn't a big job, quick and easy to do.

After your second kid you'll be looking to sell anyway so save the cash for the next house.
Ryan B
3 years ago
I can't really comment if you should keep your current WH or not, but if you do decide to replace it, you may want to consider a hybrid heat pump water heater. My last townhome was all electric as well, and it came with a Rheem heat pump water heater (there are several brands on the market though). I believe it was 50 gallons. They do cost more up front, but the heat pump uses a lot less electricity than standard coil-based heating. Mine was located in the garage, and I never had an issue with having enough hot water, leaving it in heat pump only mode. The only time I used hybrid mode (heat pump + coils) is when I had several house guests over for Christmas one year and was nervous about running out of hot water for so many showers. It worked great, but wow the bill shot up using the coils!

Some potential downsides to the hybrid heat pump:

- higher up front expense

- depending on where this will sit in your house, the noise of the heat pump compressor running. It's not very loud, but sounds like a small air conditioner, and it actually will cool the surrounding air a bit. Not an issue in a garage, but in a finished basement, it could be bothersome.

- if you live in a super cold area, you might not have enough ambient heat in the air for it to work effectively in the winter in heat pump only mode. I had this in my garage in Los Angeles where the coldest it got was 30's and it worked great

Good luck with your new home.
Bruce in Northern Virginia
3 years ago
last modified: 3 years ago
An 80 gallon unit is way too big for a two-person family, but its already paid for and appears to be working fine, so maybe just run with it for a while. However, the design of that water heater seems odd, since one pipe appears to connect at the bottom and the other about 2/3rd of the way up. Most have two fittings on top.

Intermatic sells electric water heater timers, and we have found it works well to limit the water heater "on time" to about 2 hours in the morning (for showers, etc.) and 2-3 hours in the early evening (dish washing, shower, etc.). You might try that solution first, since the timers are relatively cheap, and not hard to install.

Another common solution to increase efficiency of an old unit is a water heater insulation blanket.

Bruce
Izzy Mn
3 years ago
Maybe the old owner had in serviced yearly also. Changing out the sacrificial rods and flushing it out yearly or more. I have hard water that I treat and I'm lucky to get 10 years or so out of a water heater.

New Homeowner Question about Water Heater

kudzu9

Comments (7)

jrb451

dadoes

Related Discussions

kevin9408

Ryan B

Bruce in Northern Virginia

Izzy Mn

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US