Monitoring a hot water circulating pump

[dzee]

Mark, Regarding benefit of leaving the pump running: Yes. The pumps aren't entirely free wheeling, so even if hot water is under demand, they can inhibit the flow. I can't say it's significant, but as soon as the demand ends, the water is stationary and cooling in the pipe. For example, a washing machine or dishwasher might only demand water every 10 minutes of running, so in the interim the hot water pipes cool. You might have people taking a shower then a half hour break and someone else gets in. I leave mine running whenever we're home or appliances requiring hot water are expected to run.

[dzee]

There are also these master controlled power strips that can run a separate sensor device when a timed device goes on/off. I wish Insteon made something like this that looks like a standard on/off module, but was instead a detector when the plugged in device draws power.

https://www.amazon.com/Uninex-Contro...JIA/ref=sr_1_2

Better yet, it's something like the Kill-A-Watt that detects kWh and current, not just on/off.

I have a TPLink Wifi plug that does this, but it monitors power usage when the plug is on, and doesn't broadcast the energy, just allows it to be polled from the TPLinkSmartHome plugin.

[frdaoust]

A zwave flow meter would be perfect and very accurate. Although a bit pricey.

https://www.flows.com/watertracker-z...SABEgIRCPD_BwE



Sent from my iPhone using Tapatalk

[Beowulf]

We are considering a Watts for our new construction but I'm still trying to understand some of the points. For those of you already with one and using HS to control your pump...

1. Does it impact the pressure of your hot water flow negatively? It's fine for a low-flow situation while you're just trying to circulate the hot water 15 minutes before everyone starts getting up, for example, but once showers are going you wouldn't want this pump to limit the water flow I would think. I'm hoping the pump isn't a bottleneck to water flow.

2. For those using HS (or similar) to control the pump...you just have the pump plugged into a zwave smart plug and leave the pump "always on"? From reading the manual I'm guessing you just set the timer to a full 24 hour config or is there a switch that bypasses the timer?

3. Again for those using a smart plug ( example: https://shop.homeseer.com/collection...nt=21088749126 ) do you have any way to know if the plug fails in the "on" mode? Our pump will be in a mech room with no chance of hearing it running unless you're in there. I'm sure you can hear some water flowing through the pipes when it's active but if you're sleeping or away it could be going for hours and hours...probably not good for the pump to say the least.

[joegr]

... it could be going for hours and hours...probably not good for the pump to say the least.

I'm sure that the pump would be happy to run 24 hours a day, 7 days a week. Most equipment has more wear when it switches on from being off. Anyway, the real downside to having it continue to run, is that you will waste energy (electricity, propane, or natural gas) heating the pipes when it is not needed.

I have almost all Insteon. So far, nothing has failed in the on state.

[dbvanb]

The house had a recirculating pump when we bought it 14 years ago. This was before I advanced my home automation - before only x10 lights and photo eye.

It ran for all that time without a problem with flow, restriction, etc. It did have a problem with electrolysis of the copper pipe attached to it. I don't know why, but could guess.

When it finally gave out, about 1 year ago - the plastic impellers wore out and the motor still going great - I replaced it with the one mentioned here in the first post. I started using the internal timer, but then when I got into sonoff and mqtt, I just used a sonoff outlet and plugged the pump into it. Then I scheduled times with homeseer.

We don't notice if it is on or off because of the flow, just if it is off it takes 90 seconds to get hot water at our shower. I know because I have timed it. When it is running, hot water in 3-5 seconds, because of the length of pipe to the shower from the bypass.

There really would be no problem if it ran 24/7/365, as mine did. I have a temp sensor connected to the furnace which heats the hot water, and it is interesting to see that graphed. The outflow temp drops 60-90 degrees when it is off in the summer and we are not heating the house as well, so I think it is saving a lot of energy to only run it when needed.

I have an LED connected to a nodemcu(esp8266) which turns on when the pump is running, as I mentioned in a previous post. One in every bathroom so I know if the water should be hot. I have become dependent on the LED. One of the downfalls of home automation.

Bruce

[Beowulf]

...
I have an LED connected to a nodemcu(esp8266) which turns on when the pump is running, as I mentioned in a previous post. One in every bathroom so I know if the water should be hot. I have become dependent on the LED. One of the downfalls of home automation.

Bruce

Thanks. So to have it powered and controlled by the sonoff do you just set the timer on the Watts to be 24/7 or is there a switch to bypass the timer on the pump? I'm just trying to understand how you get around the physical timer built onto it.

I'll read up on the sonoff plugs here and outside the forums as well. I am familiar with messaging platforms (having used IBM's MQ at work for about 15+ years) and moving into some lighter versions now and have seen a lot of MQTT usage around here. As long as a solution is not cloud-dependent I'm pretty open to seeing what it can offer. I only considered the zwave plug initially because it seems like a pretty simple and immediate plug-and-play (no pun intended) use with a starting HomeSeer setup.

[dbvanb]

The pump has a switch for the timer which can be set to off or bypass, which basically means it would be on all the time.

For the mqtt messaging, you do have to have a "server" running on a computer. I use a raspberry pi and misquitto.

The raspberry pi is in the HVAC closet, and I have connected multiple temperature sensors, which measure the hot water tank and the outflow lines from the furnace to several heating zones and the hot water tank. The values are also sent to Homeseer via mqtt. Homeseer also sends the mqtt message to the nodemcu(esp8266) modules in the bathrooms to turn on and off the LED

With the local misquitto server, no cloud is necessary. For the sonoff, it does require flashing new software, ie tasmota, to connect directly to your own network, and not have to use the cloud service which the factory software uses.

Tasmota also uses mqtt. So I send a mqtt message to the sonoff from Homeseer.

With tasmota, the sonoff does have a web server (local), and this allows you to turn it on and off from a web page, outside of Homeseer. This still sends a mqtt message back, so Homeseer keeps synchronized with the state of the sonoff. You could check it also to see if the pump is on or off.

It also has built in timers which could be used. Lots of options, your choice.

Sorry this has gotten away from Insteon.

Bruce

[Dan the LAN man]

I dove deep and installed 1Wire temp sensors (UltraJones' 1Wire PI) at key points in the house's hot water lines to form dynamic feedback loops with an appliance module for recirculating pump motor control. I recently replaced the Insteon appliance module with a UPB version, as that supports a "maximum run time" (hardware watchdog timer) setting of two minutes - more than it should ever take to preheat the hot water pipes. My closed loop system was developed for a 40 gallon heater and Watts Premier pump, which has since been replaced with a Rheem tank-less water heater system and pump, plus PEX hot water return lines. A return line was too difficult to install from kitchen, so I dropped in a Bosch 2.5G electric hot water booster there. All aspects of hot water system is automated, based upon lifestyle routines and activity. Entire family loves instant hot water and I like conserving water, energy and wear (oh - and I love automation).

[jvm]

We are considering a Watts for our new construction but I'm still trying to understand some of the points. For those of you already with one and using HS to control your pump...

1. Does it impact the pressure of your hot water flow negatively? It's fine for a low-flow situation while you're just trying to circulate the hot water 15 minutes before everyone starts getting up, for example, but once showers are going you wouldn't want this pump to limit the water flow I would think. I'm hoping the pump isn't a bottleneck to water flow.

2. For those using HS (or similar) to control the pump...you just have the pump plugged into a zwave smart plug and leave the pump "always on"? From reading the manual I'm guessing you just set the timer to a full 24 hour config or is there a switch that bypasses the timer?

3. Again for those using a smart plug ( example: https://shop.homeseer.com/collection...nt=21088749126 ) do you have any way to know if the plug fails in the "on" mode? Our pump will be in a mech room with no chance of hearing it running unless you're in there. I'm sure you can hear some water flowing through the pipes when it's active but if you're sleeping or away it could be going for hours and hours...probably not good for the pump to say the least.

If you're doing new construction, one piece of advice is to have dedicated re-circulation return lines from the farthest point (or if you have multiple end-points, from each of the end-points). They work much better than those under-sink valves that are typically used when you install the pump after your water lines are already sealed in the wall. And dedicated returns should not add any significant plumbing cost (a 100 feet of 1/2 inch PEX return line is less than $50 at HomeDepot!).