The kitchen and bathroom in the attached apartment to my house is far from the water heater. I was thinking of installing a small electric water heater in line so they could get hot water quickly rather than wait for it to travel from the main water heater. I would hook it up in line, in other words the hot water coming from the main water heater would go into The cold side of the auxiliary water heater and then out the hot side and then continue to the kitchen and bathroom. Any ideas? Pros? Cons?
In-line water heater.
- Thread starter Fmkehoe
- Start date
Help Support Plumbing Forums:
1. you need a lot of amps and large wire to power enough instant electrical to serve the load noted.
2.Most instant water heaters are just 3/8".
A small electric water heater will need a T & P line piped to the exterior.
Best solution in most cases is to do a recirculating loop with controls. https://gothotwater.com/product-category/residential/
2.Most instant water heaters are just 3/8".
A small electric water heater will need a T & P line piped to the exterior.
Best solution in most cases is to do a recirculating loop with controls. https://gothotwater.com/product-category/residential/
Nukedaddy
Well-Known Member
Laing, Grundfos and a few others make thermostatically and timer controlled circulator pumps for the purpose described. I have one in use at my home. Works fine, but there is a loss in energy efficiency..
We had a similar situation when we bought our current house 12 years ago. the master bath/shower is about 70 feet from the main water heater. I installed a 2 gallon tank-type 120 volt heater in the crawl space under the bathroom. It works great, we get hot water quickly and the temperature does not change during a shower. Runs on a 20 amp breaker, works great.
thanks all. Russ Smarts reply was what I had in mind. Not “instant” hot water, just a smaller, closer source of hot water. I don’t suppose it does any harm running hot water thru a water heater. It will just stop heating when the supply water is already up to the desired temperature.
Jeff Handy
Pro Handyman, NOT A Pro Plumber
Forget the double heater setup.
Install a recirculating pump, and a dedicated return line.
You don’t want to use the cold line.
Everything else is throwing parts and money out the window, and just adding more clunky and hard to hide elements likely to fail.
Install a recirculating pump, and a dedicated return line.
You don’t want to use the cold line.
Everything else is throwing parts and money out the window, and just adding more clunky and hard to hide elements likely to fail.
Jeff Handy
Pro Handyman, NOT A Pro Plumber
Maybe the pros on here can give some instructions, if you describe or draw a diagram of your existing plumbing set-up.
Diehard
In Remembrance
If you do decide to go with a recirc pump and dedicated recirc line, you may want to give some thought of the control of the pump.
1. Manual on/off switch, located in some convenient location. OR
2. Auto on and off based on a timer. OR
3. Aquastat to turn pump on and off based on return water temperature. OR
4. Combination of 2. and 3. together, where aquastat will only turn pump on and off based on time set on timer.
1. Manual on/off switch, located in some convenient location. OR
2. Auto on and off based on a timer. OR
3. Aquastat to turn pump on and off based on return water temperature. OR
4. Combination of 2. and 3. together, where aquastat will only turn pump on and off based on time set on timer.
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Diehard
In Remembrance
I don't think a small electric tank type water heater would be that bad.
Of course you could easily have a bypass line on it in case it went down. Of course your main unit could go down too. But if that was the case you'd still have the use of the added unit.
I would look at the pros and cons of each system with recirc system needing some type of controls to help efficiency. Particularly if much of the existing pipe is not insulated.
Also, sounds like a long run of new piping back to the existing water heater
Of course, water heater needing electric service and P&T relief valve drain line to an approved location.
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Dan the Plumber
Active Member
Actually, if you put a 4 gallon electric 120 V unit in line as you say it will provide enough instant water for every purpose except a shower and the people showering can just wait for the hot water. I just did this at my house, kitchen sink, after 25 years of wasting water and time waiting for that water to get hot. Now I can wash my hands, fill a pot, wash a few dishes, fill the dishwasher all etc. without having to wait at all for any hot water.I can’t believe what a difference it makes not having to wait five minutes for the water to get hot just to do those little things.
We only have a 2 gallon inline tank type heater and I don't have to wait for hot water, the 60 feet of cold in the line mixes in the heater and I don't notice any temperature change. As far as the heater going out, I think it's a more reliable system and more energy efficient than running a pump!
Diehard
In Remembrance
You may have 60' of 1/2" which would be about 5/8 of a gallon.
While Dan may have 3/4" piping.
While Dan may have 3/4" piping.
Dan the Plumber
Active Member
There isn't a whole lot of price difference between a 2 gl. and a 20 gl.... The important thing is the 120v element so you don't have to run new wires,
You could try a grundfos instant return system.
