Remote Control For Hot Water Recirculation Pump

[Beemer533]

These use the pump to push water back via the local cold water line at the fixture. Any other fixture on the cold leg then gets hot water.

Yeah, I realized that, but I missed that the OP said this was a new build.. I definitely wouldn't use this on a new build..

 

[wssix99]

I am building a new house which will have a garage-mounted tankless gas hot water heater.

BTW - If you haven't planned for it yet, you'll also need a wall drain box for the condensate line coming out of the boiler. (We didn't plan for that and ended up having to inconveniently run it to a floor drain, which I don't expect you'll have in your garage.)

I'm happy to be the guinnea pig here. We just installed our recirc pump with timer yesterday and already have issues:
- The timer (the one on the pump or a cheap wall timer) will only run for 30 minute intervals. During that 30 minute interval, the recirc water will heat up and then the heater goes in to a short-cycling mode as it keeps that water heated up to temperature.
- The recirc pump and heater keep the water piping hot in the lines - much hotter than the heater can produce on demand. So... when I took my shower this morning, the water was scalding hot and then tapered off to "normal" heat after all the super-hot water worked its way out of the lines.

Given last night's lessons, I think a thermostatic control (aside from the one on the water heater) is an absolute necessity. (So the recirculation temperature can be kept in line with what the heater can produce on-demand.) The downside to the thermostatic recirculating pump model is that it doesn't come with the flow control that the non-thermostatic pump does.

In order to control the recirculating temperature like I want, shut the thing off at night, and also keep the variable flow control, I think I'll probably end up with a custom thermostat/timer setup, using the standard pump that comes with the flow control off the shelf.


^ I know this doesn't address the remote control option requested in the OP, but I also think that is a tricky one. I'm not sure yet how long it takes our lines to go from cold up to temperature, but it does take several minutes. I would probably forget to trigger the system in time to get the lines hot before I want to use them.

I wonder if there is a good motion controlled solution that would sense you up and walking around the house to turn the system on?

 

[yeldogt]

Look at the TACO products .. The Smart Plus and the Genie. The Genie can be used both w & w/o a return line.

TACO also makes the wireless switch -- they also sell the temp sensor.

 

[roscoe2000]

A tankless water heater operates on the principle that you are heating cold water up to say 120 deg. It is design to raise the incoming water temp over the out going water temp say 70+ deg. It is not made to throttle down. Something akin to driving dragster in the mud. It's recovery rate is a lot higher than a tank type heater. That is why your water was extra hot. It is in design of unit. You may also shorten the life expectancy of you tankless heat cause with the pump off, you are not removing the heat from the heat exchanger.

You best solution is go to a point of use water heater, which will produce instantaneous hot water on demand. Or just insulate the return line and let the pump cycle as needed.

Using two stats to control the same loop is asking for trouble, you could control the the pump with a flow switch, but then you need to shut off the tankless unit prior to the pump stopping. That is not impossible with today logic circuits, but few plumbers will be able to handle future repairs short of pull it all out.

We had a saying KISS (keep it simple) or make it idiot proof.

 

[roscoe2000]

A tankless water heater operates on the principle that one you are heating cold water up to say 120 deg. It is design to raise the incoming water temp over the out going water temp say 70+ deg. It is not made to throttle down. Something akin to driving dragster in the mud. It's recovery rate is a lot higher than a tank type heater. That is why your water was extra hot. It is in design of unit. You may also shorten the life expectancy of you tankless heat cause with the pump off, you are not removing the heat from the heat exchanger. You best solution is go to a point of use water heater, which will produce how water on demand. Or just insulate the return line and let the pump cycle as needed.

 

[rharman]

When we remodeled 20+ years ago, we had recirc pumps installed (two water heaters). They ran 24x7. A couple of years ago, we finally wised up. Tried putting them on a timer running a few minutes every few hours - that was OK but not ideal.

Finally settled on an X-10 unit with a remote upstairs and one downstairs. Works great. Our electricity bill went down tremendously.

Now, we're down to one water heater and one pump - more savings.

 

[wssix99]

A tankless water heater operates on the principle that one you are heating cold water up to say 120 deg. It is design to raise the incoming water temp over the out going water temp say 70+ deg. It is not made to throttle down. Something akin to driving dragster in the mud.

The newer whole house units are more advanced than that. Ours is a dual unit that operates as a water heater for the house supply and also as a boiler for the radiant floors. (It only operates in one mode at a time, giving preference to the house water supply.) The unit is able to heat water of any temperature, can adjust the heating accordingly, and also has a fan to provide additional cooling when the unit gets too hot.

 

[Refuse1]

I recently had a tankless water heater installed and went thru this same issue. Doing some internet research, I stumbled on this guy who seems to have the solution (for what I want). His system senses flow on the hot water circuit. When it see's a demand, the flow sensor actuates the pump for a pre-determined amount of time. All you need to do is turn a hot faucet on then off and it will begin circulating the water.

http://www.fasterhotwater.com/DRS - T coupon-code.php

I have no first hand knowledge or affiliation with this company. After seeing the normal timer based pumps, I found this info and asked my plumber to order & install it. It is not installed yet so I have no performance to report.

 

[wssix99]

I recently had a tankless water heater installed and went thru this same issue. Doing some internet research, I stumbled on this guy who seems to have the solution (for what I want). His system senses flow on the hot water circuit. When it see's a demand, the flow sensor actuates the pump for a pre-determined amount of time. All you need to do is turn a hot faucet on then off and it will begin circulating the water.

http://www.fasterhotwater.com/DRS - T coupon-code.php

I have no first hand knowledge or affiliation with this company. After seeing the normal timer based pumps, I found this info and asked my plumber to order & install it. It is not installed yet so I have no performance to report.

This is interesting. I suppose the end effect is just like having multiple faucets open at the same time to flush the cold water out of the lines faster?

 

[KCT]

Here's the solution we came up with: A 3-way switch system on 1 circuit with a timer (all hard wired). There's a Levitan LTB timer switch at the bathroom and a Levitan VP0SR-10Z "coordinating switch remote" in the kitchen. The bathroom switch (which is closest to to the water heater in in the garage) has 5/10/15/30 minute timer options. The remote switch in the kitchen will signal that timer switch to repeat the last number of minutes pressed. Of course, the number of minutes is not important since all I/we really want is for the pump to turn on, so the hot water starts circulating, and then turn itself off so that it doesn't get left on due to human operator error.
Background: I wanted a 3-way switch system with a timed shut off. I have a hybrid electric water heater and a recirc line that has been managed by a Grunfos pump's simple daily timer. The water is a great temperature and available promptly in my kitchen & MA bath when the recirc pump is on but because my schedule is not predicable, I hated the daily timer system.

 

[volleyball]

There are tankless units that have a recir. circuit built in.
I had thought of getting one but I reduced my run lengths instead.

 

[Charles (in GA)]

A tankless water heater operates on the principle that one you are heating cold water up to say 120 deg. It is design to raise the incoming water temp over the out going water temp say 70+ deg. It is not made to throttle down. Something akin to driving dragster in the mud. It's recovery rate is a lot higher than a tank type heater. That is why your water was extra hot. It is in design of unit. You may also shorten the life expectancy of you tankless heat cause with the pump off, you are not removing the heat from the heat exchanger. You best solution is go to a point of use water heater, which will produce how water on demand. Or just insulate the return line and let the pump cycle as needed.

A gas tankless is designed to maintain a set temp, but will throttle the gas/fire up or down to maintain the set temp based on flow. They do, however, over fire at first and then settle down, so you will get some overheating at first.

Whole thing with a tankless system is you have to have a change in thinking. Turn on the hot water when you first need it and leave it on till you are finished. Otherwise you will drive the unit crazy firing up and shutting down. Whole different mindset to using one.

Charles

 

[wssix99]

Thanks again to easyrider13 for putting this thread out. It has been most helpful to me, personally. (I would probably continued to be bitter/stubborn and cursed my recirculating system until the end of time.) My plumber doesn't have a lot of experience with these and sent us in a bad direction.

I'm looking forward to seeing what the OP settles on. BTW - I found that my recirculating system takes 5-6 minutes for the lines to heat up from a cold condition. I don't know if this changes things for this situation, or not. It'd also be interested to see how long KCT's system takes to heat from cold.

I ended up switching out my variable speed Laing pump for it's variant with the adjustable thermostat and it made a huge difference. I was able to dial in the recirculation temperature at the pump, which eliminated the overheating of the recirculation lines. All is wonderful.

 

[wssix99]

Rather than run the heater and pump for hours each day, I would prefer to install a wireless remote control in the kitchen, bathrooms and laundry that would turn on the recirculating pump (and heater) for perhaps 3 minutes to get hot water into the lines.

Any updates on this? Have you installed the system yet? As I get more experience with my system, I'm getting a better appreciation for the need for this.

Initially, I was wishing that I ran extra copper to run contractors/relays to turn the pump on but with the advances in home automation recently - I'm thinking that remote timers may be the way to go.

 

[Tomfixin]

All roads lead to Rome . Some are subjectively "better" than others depending on the travelers wants and desires.

I Installed my first tankless this year when I replumbed my 1953 raised foundation house in Pex A. So I wanted to have a recirc pump on the system that would allow me to remotely turn it off and on when we needed hot water. Several here have mention that having a small tanked water heater is the ticket. Yes if you want hot water fast at every faucet and shower head without having to press a button and wait a minute this is the ticket. That said, You have the expense of the tanked water heater and then the constant heating of that water as the recirc pumps runs even if it is on a temp stat that only runs it when the pipes get to a certain degree you are heating a lot more water every day than if you are willing to use a wireless switch system that turns it off and on as needed and wait the minute or so to have your hot water wherever you want it. I did run a dedicated recirc return line rather than run it back via the cold water line...either way works but you do end up with a little hot water in your cold line if you do it via the cold water return.

I am using a Taco 003 circ pump and it is turned off and on by a wireless remote switch that I paid $6.99 for. I bought 3 so I could use the flat grey on off switches in 3 locations ...and I end up with a couple extra wireless controllers if the first one fails... These are out of stock right now on Amazon but there are a ton of similar products there.



OK so that turns it on but what if I forget to turn it off. dang running that tankless for hours on end for nothing...not good.....enter the AH3-3 time delay. They run between $10 and $15. You can buy them with various time ranges the one I bought was a 0-60 minute range. I would buy one next time that has a smaller time range because trying to get this to shut off after a minute and a half took a bit of delicate dialing. I'd go for a 10 minute timer range next time.



It took a bit of head scratching to get this wired so it would function as I wanted but now when I hit that wireless remote the pump turns on and I have the timer delay set to turn the pump off after it runs for 1 1/2 minutes. When we want hot water in the furthest part of the house we hit the button twice ( to turn the wireless switch itself off and back on ) which actuates the timer again. in a minute or so we have hot water at all faucets and shower heads...definitely the most cost effective and energy saving way of having almost "instant" hot water without sending 3 gallons or more water down the drain to get it or having to run the water heater more than it needs to. The minute or so "wait" to me is worth it.

Happy as a clam

 

[justsam]

Looks like somehow another Zombie thread has come back from a 7 year hiatus!

For what it is worth I have been using a Grundfos recirc. pump controlled by an Alexa module for years now. No issues.

 

[Tomfixin]

Looks like somehow another Zombie thread has come back from a 7 year hiatus!

For what it is worth I have been using a Grundfos recirc. pump controlled by an Alexa module for years now. No issues.

100% YES "If" you use alexa, google or siri the power modules are simple and I know at least with Google you can say turn the XYZ switch on for 2 minutes and it will turn it on and shut it off. The wireless button system I came up with, once set up is simple stupid...no brains no headaches for the less tech savvy members of the family.


Now that I have figured this all out the way I did it I come to find there is this company pasted below that solves the problem in another way...Basically a little module and a flow meter that you hook up inline This part of the set up is @ $200 using this set up you open the hot water valve wherever you want hot water and it activates the pump to run for 3 minutes...You wait a minute or two and you have your hot water...similar to my set up..."IF" you want continuous hot water "on demand" you add their "constant hot water" module to the existing kit and it checks the hot water line temp every 15 minutes. If it is below 95 degrees it runs the pump until the line gets back up to hot.; You can schedule that constant to only run during your normal waking hours where you want constant hot water.....Innovative solutions for the Tankless game..

 

[wssix99]

For posterity, I got rid of all this stuff, made my recirculation pump a regular plug-in model and put it through a Wyze smart outlet. We can control it from our cel phones, computers, etc. and have several timers set.

When we turn it on outside of the programmed times, we don't use the ON-OFF function, but set a one-time timed routine so it automatically shuts off when we are done. Even if we forget, it will reset when it hits the next programmed cycle.