In a new-to-us house and we can’t seem to get the water to get hot.

Water was warm (104f) out of the nearest faucet with water heater set to 120f. I bumped the top and bottom thermostats to 135f, and it really didn’t seem to help any. I’m at 108f now.

I shot my temp gun near the top and bottom panels and got 130+ reading, but can’t get it to come out of the faucet anywhere near that. Water pressure out of the hot water line seems just fine. Not a single faucet in the house gets above 105-110f

Any ideas?

I am not a plumber and don't know jack shit about water temperature, but how long are you running the water before taking a reading?

I think the below may be considered:
1. It would have to push the cold water out.
2. It would have to warm the pipe.
3. There are anti-scald valves in the showers.
4. IF sinks are a single handle - there will ALWAYS be a blend of cold water into the output water.

Thanks, it’s a 55 gallon tank and I’ve let it run on hot-only with a dual handle faucet. It’s just mind blowing that it won’t get hot, even after running hot only for 5+ minutes.

1 bad heating element?

A lot of fixtures have a scald guard.

I think I figured it out!

No idea why anyone would want to do this, but it has a cold water line that runs into the hot water outlet from the heater. Guessing it’s anti-scald as some have mentioned. Backed it all the way out and got 114f. It’ll do for now but I’m probably gonna remove it when I get some time.

It’s always mixing with cold water. Showers/tubs have an adjustment on how far you can increase the hot side of the mix. Probably sink faucets do too but I’ve never messed with those. Should be able to Google instructions on it.

Never seen a set up like that ........ What's the little tank coming off the cold supple line for?

Looks like you need to remove that line from the cold supply and hot and plug the holes . Don't forget to cut the cold supply off . It's got two valves .........

From my understanding, the small tank is an expansion tank. I think they’re required by code now?
But two shut off valves is to be sure, to be sure!

What kind of faucet are you trying to get the water from?

Hot on left. Cold on right?

Single handle with hot progessing from cold to hot? Mixing valve stop may not be set where you need it.

I’d do away with all of that craziness

its a thermostatic mixing valve. Primary design is to allow the boiler/water heater to be set at a high enough temperature to kill all bacteria but not scald anyone using it. Manufacturer spec calls for 140deg inlet temp and approx 120ish deg outlet temp downstream of cold line connection. If you don’t want it, delete it. I wouldn’t remove the expansion tank, contrary to popular opinion.

I have had multiple water heaters through the years and I had never seen an expansion tank, including the houses I lived in growing up. I am about to install one now due to the water department installing back flow preventer valves at the meters. When either of my two heaters are emptied, the pressure rises and one starts dripping from the pressure release valve. I didn't have the issue (same water heaters) before they put the backflow preventers in place.

I keep mine at around 110 to 115. I have a little one. Wife complains. Hell it save energy.

Yep, don't remove the expansion tank, they are better than just a popoff valve, unless you don't mind the leaks from the valve. The pressure build up is not worth it to me.

I didn't see it, you did turn the thermostat up on it, correct? I just wanted to make sure, kind of like a computer, the first thing you check is it it plugged in, is it turned on, are all the cables connected properly. Also, new home doesn't mean everything works properly, have someone from manufacturer come check it, you get in their system for maybe a fault down the road, they already have a ticket on it there may have been a problem.

You are saving the Planet. Enjoy

That little tank may be code now , lota code things that make you say hmmmmm. I grew up in houses with tank , electric water heaters , have two now . Never had a extra tank , never any problems. I've also never seen a line running from cold supply to the hot . That seems counter productive. You're heating water then cooling it . If the water is too hot , turn the thermostat down or adjust the mixture at the faucet or shower.