Connecting Circulation to Hot Water in 54m² Apartment with Termet 20kV: Pros, Cons & Alternatives

Will someone tell me if it is worth connecting the circulation to hot water?
It has an apartment of 54 meters. I hang a condensing furnace with a tray - Termet 20kV.
17 m long pipes go from the stove to the bathroom, i.e. the entire loop is about 34 m long.
The plumbers set up a circuit for circulation.
But one of the installers pointed out that this significantly increases the costs of using hot water.
In fact, when the water circulates it cools down.
So I have a few questions:
- How much circulation will it take to use hot water? Can it be estimated somehow?
- Are there any sensor, time or thermal systems that allow this circulation to be programmed so that losses are minimal?
- Can the circulation be turned off, even when the pump is already installed? And how it affects the use of water.
- My installer says not to install the circulation system yet. If the water is cold for too long, the pump will be installed. It's a good idea?
- Exactly how long does cold water 17 meters run from a heater with a tray? Is the cold water poured loss (cost) less or greater than a well-set circulation?

Thanks in advance for the advice and answers.

bobo6969 wrote:

Pipes about 17 m long run from the stove to the bathroom

I have a stove about 3 meters from the tap. Before the flame ignites and the water heats up, approx. 4 liters of cold water flows out. You will get 2 x more.

bobo6969 wrote:

Can the circulation be turned off, even when the pump is already installed?

You can.

bobo6969 wrote:

Are there any sensor, time or thermal systems that allow this circulation to be programmed so that losses are minimal?

Sure they are, but usually it consists in lowering the temperature during the "break" and raising it during consumption. So here you will gain / lose there.

Thanks for this information.
But you probably have a flow oven and I have a storage tank, so there should be a little less cold water here.
Am I wrong?

bobo6969 wrote:

How much circulation will the use of warm water travel? Can it be estimated somehow?

I don't know if it will travel for sure. Take into account how much water you will be wasting while waiting for the warm tap water to come out. Comparing the cost of this lost water and comparing it with the cost of electricity to the pump and the loss of heat from the water, you may find yourself going to zero or even a plus if the tap is far from the stove and a lot of cold water flows out when you turn it on.

Xantix wrote:

bobo6969 wrote:

How much circulation will the use of warm water travel? Can it be estimated somehow?

I don't know if it will travel for sure. Take into account how much water you will be wasting while waiting for the warm tap water to come out. Comparing the cost of this lost water and comparing it with the cost of electricity to the pump and the loss of heat from the water, you may find yourself going to zero or even a plus if the tap is far from the stove and a lot of cold water flows out when you turn it on.

Well, is it numbered somewhere? The installer says that the water chills in up to 15 minutes in the pipes. So the circulation would have to spin this water almost all the time. On the other hand, hotels have such systems, and given the length of the installation, the costs could be enormous. So I don't know what pays off myself.

bobo6969 wrote:

Will someone tell me if it is worth connecting the circulation to hot water?

It depends what criterion will be used to judge "is it worth it"?
If assembly costs are this criterion, it is not worth it.
If this criterion is the operating costs, it depends on how you will use the water. If you wash each plate and glass by hand, and each dish is washed immediately after use, it's worth it. If a dishwasher is installed, it is not worth it.
When it comes to functionality and comfort, it's worth it.

bobo6969 wrote:

- How much circulation will it take to use hot water? Can it be estimated somehow?

- Exactly how long does cold water 17 meters run from a heater with a tray? Is the cold water poured loss (cost) less or greater than a well-set circulation?

It is possible to estimate, but without knowing the diameter of the pipes, how insulated and how the installation will be used, and what the battery capacity is, you can only predict.

bobo6969 wrote:

- Are there any sensor, time or thermal systems that allow this circulation to be programmed so that losses are minimal?

Are. Mostly, people install clocks that start the circulation at certain times of the day when the household is at home and when they use hot water in the kitchen.
But you can also use a motion detector that will turn on the circulation pump when someone enters the kitchen. Another solution is to install a bell connector and a timer in the kitchen, the so-called the stair clock, which, after pressing the button, will turn on the circulation pump for some time, e.g. for 5 minutes. But then you have to teach the household members that they must press a button before they want to use hot water.

bobo6969 wrote:

- Can the circulation be turned off, even when the pump is already installed? And how it affects the use of water.

You can. It affects as if there was no circulation, i.e. you have to wait a while for hot water.

bobo6969 wrote:

- My installer says not to install the circulation system yet. If the water is cold for too long, the pump will be installed. It's a good idea?

The pump costs a few hundred. If you can afford it, install it, because you can always turn it off. You can also add later, but it would be good to have a controllable installation, because later it will be more expensive to install. Later, only wireless systems remain.

Thank you very much. That explains a lot to me.
The apartment is for us for summer and sometimes for rent, so timing is not an option. It is also difficult to instruct guests about the button.
But a motion detector is already something. The thing is, however, that I won't pull the cable from the bathroom to the stove anymore, because the walls are just painted. But maybe there is a detector with a radio system? It would be perfect. My stove is ecocondens integra 2 plus - Termet and I think you can turn on the temperature sensor, so maybe the detector would go to the radio.
I am thinking about it, because in the kitchen the stove hangs 2 meters from the sink and has a tray, so there is no circulation there, but the problem concerns the bathroom (mentioned 17 meters). If someone does not fall into the bathroom to wash their hands immediately, but goes to the shower or uses the toilet, the detector should cool the water in the circulation.
Do I think right? So the detector in the bathroom is the solution? Convenient and economical? Is it only a radio one?
And I don't know if I understood correctly. The problem with the subsequent installation of the circulation is connecting detectors or a bell on the cable. But here I am already swept, because the walls are just painted. My only point is whether the pump can be retrofitted later. It is not a big expense for me in general, but during the renovation of the apartment I would rather postpone it.

bobo6969 wrote:

But maybe there is a detector with a radio system? It would be perfect. My stove is ecocondens integra 2 plus - Termet and I think you can turn on the temperature sensor, so maybe the detector would go to the radio.

There are radio controllers / programmers for boilers and radio motion detectors.
By doing installations for people comprehensively, i.e. electrics, alarms, cameras, automation, central heating, I usually do automation that controls the circulation pump or protects against flooding the house and turns off unnecessary electrical circuits in the absence of household members based on an alarm control panel. At this stage, these are very cheap solutions, because they are based on the already installed alarm system and anti-burglary sensors as well as the automation capabilities of modern alarm control panels.
For this purpose, I use reed detectors (installed in the door, e.g. to a toilet or bathroom) or PIR motion detectors.

bobo6969 wrote:

And I don't know if I understood correctly. The problem with the subsequent installation of the circulation is connecting detectors or a bell on the cable. But here I am already swept, because the walls are just painted. My only point is whether the pump can be retrofitted later. It is not a big expense for me in general, but during the renovation of the apartment I would rather postpone it.

In order to be able to install the pump later, the hot water must be led through 2 pipes and the place of installation of this pump must be provided, and this is what you have done. If so, you can later install a circulation pump and radio control of this pump. You can use both a button and a wireless motion detector.
Of course, if it was possible to lay the cable, it would be so much better that you would not have to replace the batteries in the button or in the motion detector. In addition, wireless detectors and buttons are more expensive than wired detectors and buttons.
For example, the Zamel Extra Free system can be used, but there are plenty of solutions of this type

Added after 11 [minutes]:

Christophorus wrote:

There are also various types of liquid flow sensors. You turn on the hot water tap, the sensor turns on the pump. It is true that not immediately, but warm water should appear quite quickly. The downside is the slightly high price of these sensors.

The flow sensors are not working, as the circulation pumps are quite inefficient and take some time to turn the water in the pipes. In addition, the incoming hot water quickly gives off heat to the pipe. Hot water will appear at the tapping point only when the pipe is already warm.

For me, for 7 years there is the cheapest Allegro circulation pump (about PLN 100), probably 45W, and connected to the contact via a primitive control clock, with a rotating dial (about PLN 12) on the pawls is set that it turns on every half hour for about 8 minutes, and in the middle night (24-5) does not turn on. The water in the pipes does not cool down for half an hour (all pipes in sponge condons)
The comfort of using the water is very nice, without a pump, especially in the morning, or after work, you had to release a lot of water to have hot water, about 12 meters of pipe.
Having several people in the family makes it very profitable to circulate.

Are you sure this is a DHW pump?
45W is something way too much and looks like a typical cast iron boiler water pump, not a domestic hot water pump.
Typical domestic hot water pumps have brass, plastic or stainless steel bodies and have powers below 30W. Good, branded pumps have power from even below 10W to 15W.
Those with cast iron bodies are only for boiler water and cannot be used for drinking water.

Seven years ago, I also had a dilemma whether to buy, many people wrote that it is not profitable, and when the pump is already some great miracles with ceramic bushings, and some firm vignettes.

And so I bought for the test the cheapest that was on Allegro, a Chinese orange rectangular can and a brass turbine attached to it, maybe I was wrong about the power, because they have 23-25Wat similar on the net.
Years pass and this test Chinese still works.
Now I can't imagine not having this pump.

First of all, DHW pumps are stainless, secondly, it is worth activating the pump with a clock or light in the bathroom.

For example, it works only when the DHW tank heats up and the water in the tank is mixed and more and the water heats up faster then compared to working without a pump.

Plumpi wrote:

Those with cast iron bodies are only for boiler water and cannot be used for drinking water.

Do you use hot water for drinking and cooking?

Sstalone wrote:

Plumpi wrote:

Those with cast iron bodies are only for boiler water and cannot be used for drinking water.

Do you use hot water for drinking and cooking?

Do you live in Great Britain or in Poland?
Only Brits have double taps, one for hot and one for cold water.
In Poland, both cold and hot water go to one tap. When pouring cold water into the kettle, you will always get at least a little water from the DHW tank circuit, i.e. hot water.

The solution to turn on the circulation is a simple device that I have installed and has been working for over half a year. The water is almost immediately, and at the same time the water in the tank does not cool down because the circulation is not working all the time. below is a link to this device. The device is called eco-circulation on youtube there is a movie about how it works.