Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [tankless]

A tankless water heater directly heats water on demand, instead of maintaining a reservoir of hot water. Use this tag in conjunction with the [water-heater] tag

6
votes
2answers
43 views

Can my home's power supply handle this tankless water heater?

So my home was built in 1960 and 15-20 years later another room was added on. There are panel boxes everywhere ha. I have mapped it all out and isolated almost everything. Anything that is ...
0
votes
2answers
50 views

Tankless hot water to heat home

I have a 1200 square foot second floor apartment that is presently heated using a forced hot water radiator system. The system is called a Paloma "Paloma Pak" heating system. It is basically a ...
2
votes
2answers
243 views

16“ center bracket to 24” center framing

I'm installing a tankless water heater (150lbs static load, 10" deep) I only have one option for installation and it is a 2x3 framed wall with 24" centers. The Top bracket is designed to mount on ...
-1
votes
0answers
28 views

tankless water heater running water out condensation line

We just installed a tankless water heater and there is water running out the condensation line as fast as it is coming into the heater. What is the problem?
1
vote
3answers
45 views

Is a tank less water heater a bad choice for a house with low water flow?

We are thinking of replacing our current natural gas tank water heater by a high efficiency tank less heater. However we have a water main issue, the house is from 1930 and the main is partially ...
0
votes
1answer
40 views

Tankless Water Heater - wasting water

It takes a while for the water to heat going to the tankless water heater and in doing that, a lot of water gets wasted. Is there such a thing as a pre-heat switch that would start the heating ...
0
votes
1answer
37 views

Tankless water heater venting

Most of the images show 90 degree angles for the venting. Can I run mine at a 45 degree angle like the image below?
1
vote
2answers
90 views

help determining amp service to my house

I'm considering installing an electric tankless water heater in my house, but need to know what amp service I currently have. I read that you should look at the amps on the main breaker to the house ...
1
vote
0answers
35 views

unique ? about venting tankless water header

I am installing a tankless water heater at the house. My question is unique because I can not find a reference anywhere in the code and the installation manual about where to place my exhaust vent. I ...
1
vote
0answers
49 views

Furnace draft inducer switch tripping

I have an older furnace and a brand new natural gas instant water heater that I installed. I only start this way because the furnace had one thing break last year, so I'm not sure if things on it are ...
1
vote
0answers
35 views

Service needed to add a tankless water heater

I am currently building a detached 250 sq feet studio in my backyard. The studio will have a tiny bathroom with a tankless water heater, a baseboard heater, and a few lights, a mini split (ac), of ...
3
votes
0answers
186 views

Tankless 240V water heater in detached garage tripping AFCI/GFCI breakers in house

We have two separate buildings, a house and a garage/workshop, about 20 feet apart, sharing the same electrical service. On the service entrance, there's a Siemens whole-house surge protector. The ...
0
votes
0answers
18 views

Replacing electric tankless water heater

I'm replacing my broken seisco 28 using 2 - 60 amp circuits with a ecosmart 18 using 2 - 40 amp circuits. Looks easy but can I use the existing circuits. I'd hire a professional but I live miles ...
0
votes
0answers
406 views

Can I use a sub-panel to supply a tankless water heater that requires three breakers?

I plan on installing a Echo 27 Tankless Water system but it requires 3 40 amp breakers. Can I install a sub panel to accommodate this and if so what size?
2
votes
0answers
273 views

Chemical Smell After Tankless HWH Install

I recently had a plumbing company install a tankless hot water heater in my crawlspace. Everything with the install works and looks great, but we are experiencing a very strong chemical smell (like ...
0
votes
0answers
197 views

Tankless water heater wiring

Need to supply a home tankless water heater with 3 40 amp breakers off a 200 amp main breaker box. What size breaker and wire gauge do I need to supply the sub panel that has the 3 40 amp breakers?
1
vote
1answer
47 views

what is a reasonable amount of condensate water produced by my pump?

I have a Ruud hi-efficiency furnace and also a Ruud tankless hot water system, both with condensate lines running down to the pump. My problem is... the pump runs (intermittently) ALL day long..lol.. ...
1
vote
1answer
60 views

17 years old tankless, fix or replace?

I have a 17 years old conventional tankless combi boiler, it has a 'spilling' 3-way and DHW exchanger clogged by limestone. Should I fix it or I'd do better replacing the whole boiler with a new ...
-2
votes
1answer
425 views

Can 8 foot tall 2“ x 2” furring strips attached to a floor plate and joists hold a 60 lb water heater? [closed]

I'm trying to hang a 60lb tankless water heater in my basement against an exterior wall and trying to figure out if I can get away with 2" x 2" pine furring strips and some plywood. Assuming minimal ...
0
votes
1answer
80 views

How to modify and redirect the tankless water heater steam exhaust away from the house?

I am seeking help from this community to come up a creative solution on how to make a minor/elegant modification to direct the steam exhaust to go outside and away from the house. Right now, it will ...
0
votes
2answers
475 views

Do I need separate expansion tanks for my boiler and hot water heater?

My hot water tank went and I'm trying to replace it with a tankless system, but the old water heater did not have an expansion tank installed with it. In my previous house I had a combination unit ...
1
vote
2answers
530 views

Can a tankless water heater outlet pressure be increased without a second heater?

My father-in-law has a five-bedroomed house with three bathrooms, two of which are in use. The household is gravity-fed with a cold water tank on the roof, and a gas-fired tankless water heater on the ...
1
vote
5answers
1k views

Buffer tank on input or output of tankless water heater?

As I understand it, in residential systems, tankless water heater are commonly paired with a buffer tank to deal with the "cold sandwich" and finite capacity of tankless heater1. This seems ...
1
vote
1answer
894 views

How to chlorinate a tankless water heater?

I live on a private well and have had a tank for a while. Every few months I'd have to chlorinate the tank (with hydrogen peroxide) to get rid of the rotten egg smell. Two local plumbing companies ...
0
votes
3answers
446 views

Tankless point of use water heater that only heats when inlet is cold

There are other questions such as this that ask about a point of use heater to provide quicker hot water, but they don't seem to fit what I want. Our kitchen sink takes a while to get hot, and I ...
0
votes
1answer
256 views

Should I go with a stainless steel or copper based tankless water heater?

I live in Southern California, Orange County to be specific, and want to replace my 40 gallon (gas) water heater located in the middle (inside) of the house with a tankless water heater (electric ...
1
vote
2answers
90 views

Should I replace my conventional interior water heater with an exterior tankless model?

I'm shopping for a tankless water heater. When the salesman talked to me, he told me they install them outside and this is better because then the tanks do not take up room inside the house. I'm ...
1
vote
2answers
383 views

tankless water heater before the reg hot water

What if I installed a new tankless water heater before the regular hot water heater, so that the tank water heater is getting filled with hot/warm water vs the 40 degrees water its getting now? Our 80 ...
0
votes
1answer
43 views

What is this “on” cap that's adjacent to my tankless water heater's service valve?

There's a "cap" next to my water heater's service valve that says "on" with an arrow. What is this "cap" and its purpose?
1
vote
2answers
78 views

What is this pipe beneath my tankless water heater?

While watching videos about draining tankless water heaters, I noticed none seem to have this beige pipe with odd silver cab at the end. Does anyone know what this is and its purpose?
1
vote
1answer
492 views

Wiring washer, dryer, tankless water heater

Trying to wire for washer/dryer combo in the garage, and we need to add a tankless water heater to get hot water to the washer. In their current location, there's a (EDIT: 15) AMP circuit for washer, ...
1
vote
2answers
1k views

Pex Pipe Freezing & Tankless Hot Water Heater Too

I have Pex pipes. My issue is freezing pipes and tankless hot water heater on the north side of my house (built in 2009) where my master bath is (the tankless is on the outside of the house on that ...
0
votes
1answer
332 views

Protecting PEX Outdoors

I am installing a tankless water heater, which is an outdoor model. We are likely to use PEX when redoing the plumbing, but because the heater is outdoors, we will need to have a short, outdoor PEX ...
3
votes
1answer
72 views

Residentail Tankless Water Heater Electrical Concerns

So the electrical install guide for Ecosmart ECO 18 requires 2 (two) 40 amp double pole circuits. They specifically mention running two grounds too which I gather would be provided if NM cable w/...
0
votes
1answer
278 views

Isolation valves on tankless heater: is this setup ok?

I had a tankless water heater installed with isolation valves. The setup that I got is a little different from what I normally see, and I'd like to make sure that this is a good solution and I'd like ...
0
votes
0answers
96 views

Tankless Recirculation Loop as Hydronic Radiant Heating

While researching ways to heat a small bathroom (28sq. ft. total), I came across a post that someone put some narrow piping above a bathroom subfloor and cemented it in under the tiling. They were ...
3
votes
4answers
793 views

Electric Water Heaters: Tank vs Tankless (Instant On) Energy Usage?

I've been told that a tankless electric water heater is enormously more expensive than a tank water. I have a 50 gallon water heater that I must replace. I have a friend who is a plumber telling me ...
1
vote
1answer
595 views

Tankless water heater - not consistent hot water output

I have a tankless with a descaler on the cold water input. When I turn on the hot water at the faucet it takes a minute or so to get hot water. Then I'll hear some banging/knocking of the pipes. ...
0
votes
0answers
68 views

Upgrade to a tankless heater

My water heater went out and I'd like to replace it with a tankless. Electrical setup is as follows: A.O.Smith 50gal water heater - 1, 30amp double pole breaker Tankless needs - 2, 40amp double pole ...
1
vote
1answer
227 views

Tankless heater that only works in the morning

We purchased a house with an existing tankless heater (installed in 2009). It would occasionally fail with error code 11 (no ignition). Over the past 2 months it has been failing more often and now ...
1
vote
1answer
87 views

Short run of propane to stove and tankless WH

I have a small stove with a propane conversion kit and a 3gpm propane tankless water heater. This is for a small MIL suite ~650 sqft. Both the stove and the water heater are on the same exterior wall, ...
0
votes
1answer
1k views

How crucial is a filter for your tankless water heater?

A plumber gave me a quote recently and told me that the tankless heater needs a water filter. This will extend the life of the tankless. How crucial is this? We do not have soft water here in Los ...
2
votes
3answers
537 views

Can tankless water heaters be used in Europe?

I just discovered tankless water heater technology while browsing alternatives to gas based water heating, more specifically the ones designed in the United States by EcoSmart. I have been trying to ...
0
votes
0answers
390 views

Is tankless water heater isolation valve sufficient for supply shutoff?

I am installing a natural gas tankless water heater with an isolation valve kit that permits easy flushing in the future. Every tank-based heater I've installed included a shutoff valve on the inlet ...
1
vote
1answer
1k views

What is the best way to mount a tankless water heater to a concrete wall?

I am planning to replace my hot water tank with a Noritz NRC98-DV tankless hot water heater. The best location to mount the new heater is in the basement on an outside concrete wall. The heater will ...
3
votes
1answer
1k views

How could a hot-cold plumbing crossover spontaneously appear?

OK, this is a weird one. Follow the bouncing ball: I have a tankless water heater I've had problems the last few weeks with the water running lukewarm instead of hot. Someone suggested power-cycling ...
1
vote
2answers
4k views

I Replaced Pressure Relief Valve on Rinnai water heater (twice!!). New one does not hold ANY pressure

I just finished replacing the pressure relief valve on my Rinnai hot water heater. Everything went well, I turned on the cold input and wham, water just started gushing out of the relief valve. All ...
1
vote
0answers
434 views

When upgrading a gas meter, do you need to install/upgrade regulators for natural gas appliances?

I live in TX and have Amica as my natural gas provider. I want to replace my tank water heaters with a tankless unit. According to the Amica tech, I will need an upgraded gas meter which would ...
0
votes
1answer
116 views

Is there an electric tankless water heater that takes multiple electric lines as input?

I currently have a 50 gallon water tank in my house and I want to replace it with a tankless system. The primary reason to replace it is space. I recently installed 2 HeatWorks Model 1 units to test ...
3
votes
1answer
743 views

Tankless water heater requirements

I'm looking at the possibilities of replacing my water heater. Currently we have an electric, 2 element, 50 gallon tank heater that is 32 years old and almost ready to go. The water can sometimes come ...