Hot Water Heaters

[Len Rowland]

 

I am considering buying a new house in David.  The house is almost complete and has the plumbing for hot water to the 3 bathrooms, kitchen and laundry room but no heater has been installed.  There is electricity run to the heater area so I will probably use either an electric "instant on" or a standard electric hot water tank like we typically use in the U.S.  The house will be used for vacations about half the year.

 

Does anyone know the advantages and/or disadvantes of "instant on" vs. standard electric hot water heaters using a water tank???????

 

Thanks for the imput.

 

Len Rowland

[jim and nena]

Where does your dad stand on the subject of "tunaFISH" sandwich? haha  How about 24/7, 365 days a year (as if some weeks don't have 7 days)?

OK, I'm done.

jim

[Claudia DeMoss]

And still another...

Me - Daddy, I just saw 2 twins.

My father - Oh, were there 2 of them?

BTW-He would agree on both counts...the sandwich and the 24/7.

Based on the other replies, I guess you can tell I supplied the gringo answer to his question! I'll keep my opinions to myself from now on. Unless it doesn't specifically apply to Panama, that is!

[jim and nena]

Hot water isn't specific to Panama, far from it actually.  Lots places in Boquete never had hot water, this one sure didn't! 

And if you are planning a move to Boquete, you can offer as many opinions as you want. :-)

jim

[wryawry]

Electric "instant" water heaters typically have an extremely high amp-draw -- check the electrical service. Additionally, hard water will compromise electrical resistance elements quickly. If you utilize a storage-type heater, plan on routine draining to prevent sediment build-up.

Co. Lic. 179-842

[jim and nena]

Another plus to tank type heaters, when the power goes out you have hot water for a shower for awhile, if you can shower by candlelight.

jim

[Keith Woolford]

Not sure why you would be going with electric when gas is so much cheaper to operate, Len, especially if you use the smaller propane tanks which are subsidized. We recently installed a gas-fired 50 gallon tank heater. Cost at Franklin Jurado was about $600. Just my $.02.

[wryawry]

Agreed.

[Judy Sacco]

When we bought our house, it had an electric water tank (storage tank like in the U.S.).  The electric bills were $90/month.  We immediately removed it and installed an on-demand gas water heater.  The electric bills dropped to about $36/month, and a tank of gas (5 gal.) lasts at least a month for the whole house.  You take in the empty tank and get a full one for $5.37.

[jim and nena]

There is another angle to this that could be a deciding factor, the house will only be occupied 6 months a year.  I would think that if the tank type heater is used, it should be drained when the house is closed up for the off season.  It would need to be refilled and heated for the next visit.

When I replaced our 52 gallon tank heater in Texas, I changed from gas to electric and added a 10 gallon heater for the kitchen/laundry use.  The 52 gallon temp is set to 100°F, the 10 gallon is set to 120°F.  My gas and electric bills combined were less than with the old gas system.  The other plus is we don't worry about kids getting scalded in the showers.

jim

[David van Harn]

Excellent solution, Jim - with a real-world look at the savings.  I will remember it and recommend it to others who ask these questions. 

Standby losses are critical in saving money with tank-type water heaters, and the higher you keep the temp in the tank, the more is lost, and the more you pay for fuel/electricity.  We used to recommend external water-heater insulation blankets to reduce standby losses, but the new tanks have thicker and better insulation.  I would recommending spending a bit more for a tank with extra insulation, if you can find one.  My current rental casa has an 30 gallon "American" brand electric "domestic water heater" (I don't know how they became known as hot water heaters, because they don't heat hot water).  After reading your post, Jim, I measured the water at the tap as 75°F at ambient, and 145°F after flowing long enough to reach full hot.  I turned it down to 120°F and will verify the actual temp tomorrow with a thermometer. and fine tune it if necessary.

In my years as a solar heating system designer and salesman, we sold the solar systems to preheat domestic or commercial water.  However, the water in the solar storage tank could get as hot as 180°F, which is way too high for domestic use.  We included a mixing valve with the systems to blend it with cold water as it came out of the solar tank at 120°F.  When the solar tank dropped below 110°F, we recommended a "modulating" flame natural gas or propane "instant" heater to kick it up.  Solar heating is much easier to implement here in the tropics, where freezing is not a problem, but the equipment cost is fairly high, and I'm guessing that you would have to use a lot of hot water to justify the expense of a modern solar HW system.

My limited experience in Panama is that in-line heaters require a certain flow to keep heating, and pipes in concrete/concrete block cool quickly  At my first rental, I often had the warm shower water go cold, then had to step aside, turn the water off, than back on at a higher flow rate, and wait for the new batch of hot water to arrive from the outdoor heater on the other side of the building.  I don't know if the quality of the in-line propane heaters affects their ability to stay on at lower flow rated, but my limited experience was that dealing with at least that particular in-line propane heater was a pain in the butt. 

Lower Water Heating Temperature for Energy Savings (from energysavers.gov)

You can reduce your water heating costs by simply lowering the thermostat setting on your water heater. For each 10ºF reduction in water temperature, you can save between 3%–5% in energy costs.

Although some manufacturers set water heater thermostats at 140ºF, most households usually only require them set at 120ºF. Water heated at 140ºF also poses a safety hazard—scalding. However, if you have a dishwasher without a booster heater, it may require a water temperature within a range of 130ºF to 140ºF for optimum cleaning.

Reducing your water temperature to 120ºF also slows mineral buildup and corrosion in your water heater and pipes. This helps your water heater last longer and operate at its maximum efficiency.

While there is a very slight risk of promoting legionellae bacteria when hot water tanks are maintained at 120 degrees, this level is still considered safe for the majority of the population. If you have a suppressed immune system or chronic respiratory disease, you may consider keeping your hot water tank at 140 degrees. However, this high temperature significantly increases the risk of scalding. To minimize this risk, you can install mixing valves or other temperature-regulating devices on any taps used for washing or bathing.

[jim and nena]

I was raised poor, David, we squeezed dimes until we got 3 nickels.

The long pipe run from the main heater to the kitchen/laundry meant waiting for hot water at the sink, dish washer, and clothes washer.  The dish washer wasn't a problem as it heats its own water but waiting on the clothes washer and especially the sink to get hot water was wasting time as well as water.

When we gutted the kitchen for the redo, that was our chance to make it all better.  I wanted to add solar into it (did I mention the 3 digit temps today?), but we ran out of time as I was still working.  I left stubs in place so maybe now I will get around to it.  I can easily believe 180°F temps from solar here so some blending would be in order.

The point of use heaters on the shower heat are what we use at mom's house but she usually doesn't use it.  I could never quite acclimate myself to 55°F showers in the morning but early afternoon showers felt good.  Many of the locals will duck into the shower just after their siestas.

Panama has never taken full advantage of all the natural energies available but for it to work, there must be a multiple approach.  Solar is good except during the extended rainy season.  If it is raining, the chances are the winds are blowing so turbines would be online.  The systems for individual homes would be best and could take one almost completely off the grid.  If there is a stream/river nearby, hydro scaled to family sized needs would pick up the slack.  The idea is to use a network of technologies to keep the power going.

jim

[Keith Woolford]

I didn't bother to get Into it with my previous post but I did leave the existing tankless water heater and re-connected it between the tank output and the load. (electrician speak). In this fashion I can operate it as a hybrid system if I desire to, and it also serves as a backup to the tank heater. For now I'm enjoying long hot showers without valve-fiddling as in the last 17 years.