I've read so much conflicting advice from experts, I really appreciate empirical information. Is your unit far from your bath? Thank you!

what size my Rinnai s, but it's scaled for a family of 4, 2 baths, clothes washer and dishwasher. Never been without hot water due to heavy use. It's in my basement, so takes a bit for water to get upstairs, but no biggie.

Didn't realize you could do the whole house tankless. "Experts" lie. Duh.

is around $31/month for me.

I have never run out of water. It's just me and long shower? I dunno...mine are maybe 5 min?

concurrent hot water uses there are: shower + dishwasher + washer, etc.
There are guidelines provided by mfrs.

Endless hot water.

You will need to install the required electrical supply, usually a 40amp wire on a new circuit. It probably will required a disconnect switch at location. Make sure you have couplings installed with shut off valves so that next time tank is replaced the cost will be much more reasonable. A qualified P & H will follow all codes. You still need to cap the vent at roof.
In all likelihood the moisture from rains caused some corrosion at burner. This usually makes the pilot sensor malfunction. A new cap and cleaning may be all you need. With a 12 year old tank I would compare replacements as the electrical work could be costly.

Of course, amps never crossed my mind. Do plumbers usually do roof caps? I've been leaving messages at "water heater installation and replacement" businesses.

I bought a cap, probably wrong one, and climbed on the roof. Then I got the heebie jeebies so this septuagenarian hundred-pounder stuck the cap in the pipe and climbed down. Don't want to go up again.

Didn't think electric would need venting. Obvious why this isn't one of my DIY projects.

Thank you.

You would need a separate 220/40amp for the DHW and no venting required. Please do not get on your roof again.
Being a septuagenarian myself I have discovered that falling is no longer an option.

I've limited myself to six foot ladders from now on.

but I'm very disturbed that you're not getting calls back. Do any of the plumbers have websites?

And good luck to you.

About a year and a half ago I replaced a water heat that was a good 25 years old, so I'd been lucky it lasted so long. Fortunately, I was able to find an excellent local firm and was only without hot water for three days.

and completed what's-your-issue in two online forms, and left messages at two others. Since it went out two months ago, I couldn't claim emergency, yet I suspect that's why no call backs under CV restrictions. I'm going to try again next week, hoping to reach a live person as our state continues relaxing restrictions.

Depending on how much work any given plumber or company can realistically take on now, I see the problem. Hope this doesn't escalate to an actual emergency and that you can get a plumber in reasonably soon.

For what it is worth, I have a master plumber license in three states.

The most cost effective way of dealing with your issue is have that vent cap fixed. That will have to be done regardless of what other steps you take. I believe that the missing cap is allowing wind to blow out your pilot.

It takes no special skill to replace that cap, it simply twists on, so no plumber or gas mechanic is needed. Anyone who is not afraid to go up on your roof can fix the thing. If you don't have the old cap, you can buy one cheaply at Lowes or Home Depot.

Since you have to fix that issue, do that first. If you don't fix it, you are allowing rain and bugs into your home. You may also have a problem with a thermocouple, but I doubt it. Thermocouple replacement is one of the least expensive repairs to make.

To answer your question about sizing the water heater, even a 30 gallon gas tank-type heater would serve one person without a problem.

A tankless water heater will save money in energy use and would serve your needs, but it is going to be quite expensive to change out and it will be a long time in seeing any cost benefit. In fact, it may not last long enough to pay for the cost of installation. Tank type heaters are very simple, they last a long time, and they are easily repaired.

If you decide that you want to change to a smaller tank-type heater, do not be impressed by anything other than the energy rating of the unit. When you pay for a big name heater, you are paying for the name only. I have never been able to see a difference in quality in any tank type heater, except for the quality of their insulation and thus energy rating. It is not a big secret, your plumber makes more money if he sells you more stuff, many or most will try to sell you more than you need.

Bottom line is this: If money is no issue, swap to a gas type tankless heater. If money is an issue, fix your present unit, or replace it with a 30 gallon gas heater. I would fix it.

I bought this stuck it in, heated for 20 minutes or so, loud bang, heater out, turned off heater, turned off gas, wallowed in self-pity.

Because of the bang, the integrity of the vent pipe through the filthiest fifty year old attic should maybe be checked. Will a regular plumber do the roof and the attic?

I have mostly my stimulus money plus a little so it seems I should have it repaired or go with a 30 gal. gas replacement if I can find someone. Any SoCal referrals?

Thank you bunches.

If you go electric or change to another gas water heater, you'll most likely need to get a permit.

I will call people listed as plumbers next and forget the non-responding installers.

I have a strong suspicion that the noise you heard was not related to the new vent cap. By all means, call a licensed professional to check out your problem. If the city requires a permit, pay for the permit, if nothing else it will be worth the cost for peace of mind.

Plumber came and wrote the vent cap properly installed (it's not, I was on the roof) and the old heater safe. Told me if I let inspectors in there's no telling what they'll find as he nodded at my 50 year old stove.

Told me if I flip that lever I can stop water from filling the tank. Having learned my lesson, I responded that was funny because before he passed my husband always turned off the water to the house when he drained the tank twice a year.

11 months, no running hot water because 1) a tiny old lady doesn't know anything, or 2) because I don't have $200,000 to rehab my house, I couldn't possibly have $2,000 for a water heater.

The fix could be a small adjustment requiring no parts, but it sounds a bit more serious.

Any referral is welcome. The unit went out when the 50 year old vent cap was knocked off by a golf ball.

Is there any way to fix that, or does the unit need to be replaced? Bear in mind, that money is definitely "an issue". I've been filtering through DIY videos for the past couple of days, but it would be great to get some advice from a DU pro. I found a 5 y.o. tank on ebay, that says it's in excellent condition, but for some reason, I feel like I might be buying someone else's troubles.

Yorba Linda

They are also 5x the price of a conventional heater. Maybe a little less, but WAY WAY more expensive. They also require professional installation to be correct.
I chose to go the route of conventional gas, (and being quite handy) installed it myself.

My 2c..

Gas replacement is my plan, now. I haven't figured out how to turn the cold water off without standing on my washing machine. My ladder doesn't get close enough.

If you can turn that off, it will cut off your water supply, Any residual can be drained by opening up all the faucets. Then you can install the new heater.
If its' too much trouble for you, get estimates from licensed plumbers. Most will offer payment plans, but at least you'll have piece of mind it was done correctly. And you'll get a warranty.

Best of luck.

Thanks for pointing the obvious which should have been clear to me. I've been trying to get a professional and plan to work the phones again Tuesday. Between my county being a bit more open and the long holiday over, I hope to find someone willing to go in the attic and up on the roof, as well as the swap.

My lack of skills combined with being a small, old woman make this not a DIY project for me. I have funds.

I thought you were something other than a small old woman. I guess I take too much for granted on these posts.
That being so, I URGE YOU to get several estimates from LICENCED plumbers in your area. I'm certain there are plenty that need the business. Don't stop until you have at least 3 good estimates with WARRANTYS for their work.
If you ever need advice in this area, please feel free to email me and I will do my best to help you. I HATE IT when people are taken advantage of......
Best Regards,
AZ

I have had my last two 50Gal Gas water heaters rust through and leak at about 3 year mark each.
They were both the same Bradford White model. The 1st was replaced under warranty.
Looking for a better brand to use.

In my experience even cheap water heaters last a long time under the right conditions.

If you are lucky enough to have fairly soft water that's relatively ion free, then your hot water heater will likely last a very long time without having to do anything to it. Some of us aren't that lucky. In this case you have a couple of defenses. The first and easiest is to follow your manufacturer's maintenance recommendations, which involve periodically draining some of your water heater's water. The other thing is anode inspection. All steel water heaters have a sacrificial anode which will degrade over time. The ions in the water attack the anode instead of your tank. If the anode calcifies or simply erodes, then this defense is gone and those ions will start attacking your tank eventually causing failure. If you are experiencing failure at the 3 year mark, you might want to check your anode every year or so and replace as necessary. All steel tank type water heaters have these anodes and regardless of which brand you have they will all fail if this anode becomes ineffective. If your anode is failing due to calcification, and I suspect that might be the case here, you might want to consider turning down your hot water temperature. Higher temps result in higher calcification.

See pages 22 and 23. https://s3.amazonaws.com/bradfordwhitecorp/wp-content/uploads/residential_gas_natural_atmospheric_vent_naeca_compliant_iomanual_51012.pdf

to buy based on energy efficiency and price, not brand. There is not near as many water heater makers as their is water heater "brands." The same factory can make a dozen brands. Same heater, different case. I suspect that in my career, I installed 500 water heaters and usually if they are going to leak in the first three years, they will leak in the first three weeks. Three years is a very short lifespan for any water heater, it must have had a factory defect or either you have some very rough water. I have repaired water heaters that were 30 years old, I recently replaced my 22 year old gas water heater with an electric, and there was nothing wrong with it other than I did not want to deal with propane any longer, the truth is, I don't recall what brand ether heater was/is.....

A water heater company once sent my wife and I on a free, all expense paid, luxury vacation, to Acapulco for a week, and I didn't even push their "Brand." I did, however, very much enjoy their trip!