Dirty hot water, boiler overfilled, related?

Judging by the sight glass, I gained maaaaybe a quarter of an inch since I drained the boiler.

I noticed that there's pinging or popping from the tank. I've never heard that before. Then again, I've also never drained and refilled the tank, so maybe the noise is just a one-time thing caused by a big swing from the cold refill to the hot operating temperature.

My warranty request was approved. The local plumbing supply house has the same tank in stock. I've got to find a plumber first to proceed. How long can I keep going with a leak? For all I know, it's been leaking for months.

I'll watch it overnight and see what happens. I'd rather not pay emergency plumbing labor prices if I don't have to. Hopefully, the boiler isn't filling too quickly and I can get it swapped out next week or the week after. Thanks for the help!

I shut off the supply to the tank and left it overnight. In the morning, the boiler level was a little higher, but not as much as before. I did not drain the tank because I don't have a pump or basement drain and didn't want to carry out another 45 gallons by hand. I also didn't release the pressure in the tank (e.g., by opening a faucet). I think that was a debugging mistake because I think residual pressure in the tank could explain a small rise in the boiler level overnight.

Plumber is coming Wednesday to give an estimate.

One question I'm going to have for him is whether this is a good time to upgrade to a bigger tank. I think HTP would let me pay the difference to go to a bigger size, but I'm waiting on confirmation about that. The SSU-45 was put in 12 years ago when we had a toddler and baby. Now we've got a teenager and almost teenager. It's been fine so far, but we do occasionally notice luke warm water when showers are back to back or at the same time.

Two showers, one tub that's barely used, one dishwasher, one washing machine that's almost always run on cold, one kitchen sink, three bathroom sinks.

The SSU-60 is bigger with the same size heat exchanger that I have now. The SSU-80 is bigger still with a bigger heat exchanger to go with it. I don't have 1-1/2" water lines though. The 60 is probably a much easier swap. Can probably reuse all the existing piping. The 80 would require moving all the pipes. https://htproducts.com/literature/HTP_MKTLIT_111_SuperStorUltra_ProductSheet-01.21.25.pdf

The plumber came today to take a look in preparation for sending a quote. He recommended the SSU-60 for a couple reasons.

He thinks the old tank is probably less efficient than it could be due to build up of crud in the coil over the last 12 years. A new tank would be instantly more efficient. Swapping the mixing valve coming off the tank might help too. (I descaled it a few years ago, but it's probably due for another vinegar bath or a swap.) Going from 45 to 60 would give me that much more headroom on top of that new efficiency. He also said that they could crank up the thermostat on the tank, which can make the tank feel bigger by reducing the amount of hot water needed to reach the desired temperature at the faucet. And the 60 has similar hookups as the 45, so it'd be an easier swap.

He said they could also do the 80 if I wanted. It'd be more work with the piping, but not much more. He said one risk is that the boiler would have to run longer to heat the much bigger tank, which might send steam into the radiators in the summer. Not sure how likely that is, or if there's a way to mitigate it.

He was comfortable with recommending the 60, but said the 80 would be for the "never want to worry about hot water ever again" scenario.

I got the quotes for taking out the SSU-45 and putting in a SSU-60 or SSU-80. They're quite a bit higher than I expected. I know we're not supposed to talk about pricing here, so I'll just say that the quote is high enough that I'm wondering if it includes the cost of the new tank and they're expecting me to get paid back by the manufacturer.

The quote lists what they're doing:

• Removal old tank
• Install new tank
• Reconnect/repipe boiler supply and return
• Reconnection/repipe hot and cold
• Install new aquastat (mine seems to work fine, so maybe just some preventative maintenance?)
• Install new mixing value (provided by me—I have a spare)
• Bleed boiler
• Test operation

There's no breakdown of parts and labor though, just the total price. Too late to call them now, so I'll see if I can get more detail in the morning.

I think putting in the 60 would be really straightforward. The tank has a bigger diameter compared to the 45, but the ports are all in the same place. The 80 would require repiping, so I expected a bigger jump in price for that one.

Either way, not much more than a half day of work for two guys, or am I underestimating the difficulty? A family member had good luck with this plumber and I was hoping to just go with them, but I'm thinking I need at least another quote.

I got a more detailed quote. The price does not include the cost of the new tank.

They're figuring a licensed plumber plus an apprentice for half a day. This cost matched my expectations.

Even if I did a like-for-like replacement and stuck with a SSU-45, the new tank isn't exactly free. There's a warranty fee from the distributor that I have to eat, and I have to pay for the plumbers' time while they get rid of the old tank and do the warranty paperwork. That fee and extra time adds a couple hundred bucks to the quotes.

The upgrade cost for the SSU-60 or SSU-80 is a little higher than I expected based on pricing that I could find online. Prices vary though though and everyone has different relationships with suppliers, so maybe it's fair. This adds another couple hundred bucks to the quotes.

Finally, the "other materials" cost is much higher than I would expect. For the SSU-80, the materials cost is about the same as the labor cost. Even just swapping in a new SSU-45 comes with a lot of materials cost. The only new hardware called out is the aquastat, so they must be planning to replace a lot of piping.

Add it up and the cost is $X for the SSU-45, $1.5X for the SSU-60, and $2X for the SSU-80.

Here's a question for the experts. More hot water is better, but is there a point where the tank is too big for my boiler to keep up? I guess this gets to the maximum recovery rate that you mentioned earlier. I tried reading the manual to see what size I could get away with, but I don't understand sizing tables. By the way, I previously said that I have a PEG-45, but I was wrong: I actually have a PEG-50.

If the 45 is good and the 60 would be great, that seems like a worthwhile upgrade. The 80 seems tempting based on "bigger is better," but I'm afraid of ending up with worse performance.

45 and 60 have the same 20 sq ft heat exchanger. The 80 has 34 sq ft.

Am I understanding right that the 80 won't be worse than what I have now, should be better than what I have now, but that it just might not be as good as the brochure says it could be because my boiler isn't big enough?

If so, what would you pick? 😀

We have a 45 and sometimes get not-quite-hot-enough water when both showers are going. Two adults, two kids. One crewcut, three Rapunzels.

Could be a gunked up mixing valve that's limiting the output. That was the problem a couple years ago. Back then, the water never got hot, just warm. A vinegar bath fixed it. We get hot water now most of the time. Sometimes it's just noticeably not as hot. Maybe it just needs another vinegar bath. The plumber is going to put in my spare. Maybe that will fix it, even with a 45.

Could be scale build up on the heat exchanger. Testing done by the town says the town water isn't too hard, but I haven't tested my water. Maybe a new tank with a new heat exchanger will fix it, even with a 45.

Could be something else. I don't know.

It's not bad enough that I would have ripped out the old tank and put in a bigger one. But, the old tank sprung a leak and has to come out anyway, so if I'm going to go bigger now is the time to do it.

I'm asking for advice, not insisting I need an 80 or even 60. If I'm going to spend $X anyway and still end up with not-hot water sometimes, I'll be annoyed if I could have spent $1.5X or $2X and never had not-hot water ever again.

I decided to go with the 60. I watched this video from Taco about indirects and learned a lot.

I think 80 would have been overkill for us. 45 probably would have been fine through the teenage years, but 60 will give me a little extra oomph so that hopefully we never have to think about hot water.

Thanks for the help.