Self-construction thermodynamic water heater

[dede021385]

Hi tran,
I think to post in the good forum my self-build.

I have always been very interested in the phase change system, what clims!

I currently have a production ECS oil, and I wanted to reduce conso already important. (~ 300L / year)

So I thought thermodynamic water heater, some of you will say, but why not the solar ??
Solar is for a little later (1an I think).

My goal is mainly to recover the calories balanced by the VMC, out of the question to invest in a VMCDF too expensive for my taste and less profitable.

Seeing the prices crazy about a thermodynamic balloon, I decided to make it myself with a max recovery.

I started by installing 2 VMC in the house (it is large so 2 mandatory blocks) I completely isolated the pipes to recover maximum heat.

I have also installed insufflation vents in the rooms to return the heat when the temperature of the balloon is reached.

cost: ~ 500 €


I recovered :
a reformed balloon of 200L with a coil.
1 boiler circulator
1 compressor danfoss 1.5cv + are exchanger GAZ / WATER
wooden planks


I bought :
the R134A
the thermostatic expansion valve
1 dehydrator
1 liquid indicator
some rings 40% silver
1 digital thermometer
1 calorie counter (but I will sell it later)
Copper + fittings
2 GAS / AIR copper exchangers (condenser opel corsa + evaporator small cold room)

Cost ~ 500 €


Integration of the air / gas exchangers in an insulated wooden box, 3 air passage for maximum exchange, there is also a filter to retain the particles in order to avoid clogging of the exchangers.
I did not take pictures from inside, at the next filter change I would





Hydraulic connection on the water heater


The compressor and its organs:


The thermostatic expansion valve


Liquid light + déshy



The gas / water exchanger


Overheating:


Internal temperature and circulator


Service pressures


The complete gas plant !!!





Very conclusive test.
I climb the water from 14 ° C to 55 ° C in 4h, which represents 12kw of power, off on my energy meter I have a conso elec of 6kw.
I have an average COP of 2, I think it increased when I would have well isolated all and that there will not be so much pipe for the tests.
The air coming out of the exchangers on the cold side is 1 ° C above the evaporation temperature, so I conclude that I get the most calories.

Next DIY an anti noise box for the compressor with passage of the air extracted from the VMC to recover the heat released by the compressor (still some calories glean)

So, if it can help someone to launch

[dede021385]

I'm going to make a new half-load test of the balloon.

Water temperature -> 32 ° C
After 2 hours of charging -> 54 ° C
Calorie counter reading -> 7kw
Energy meter reading -> 2.9kw
COP -> 2.4

If we use the formula 200L x 1000grs -> 200000grs of water
200000grs X 4.18J -> 836000J
836000J X 22 Δt ° C -> 18392000J
18392000J / (60 * 60 * 2) -> 2560w / h

So I recovered 5.1kw on 7kw product, must I quickly isolate all that.

I think my calculations are good, if a specialist goes in the corner

[chatelot16]

very interesting

a refrigerator who makes us share his experience!

there is work to do! this kind of whole material is sold dismally too expensive, and it is too difficult to buy the spare parts, and almost forbidden to buy the gas

[chatelot16]

a shame to mix the units

an energy counted by a meter is measured in KWh (not in KW)

W / h does not exist

a power is in W or just kW

it's the opposite of flow

the m3 is the unit of water quantity and the m3 / h the unit of flow

in electricity it is not energy that has the simple name, but of energy flow that is called power

the energy unit is the kWh
the energy flow would be kWh / h which is simplified to be the kW just short

there is alas, especially in ecology, an abominable number of sites that make these errors of unity that make certain things incomprehensible: it is much worse than the errors of the hortograph!

[dede021385]

Hi,
the funny thing about all this is that I'm not a refrigerationist
I am in the humbug!

I agree with you, the thermo water heater is a shame the sale price, for 1 compressor fridge, 20m copper and an evaporator, it's expensive the beast ...

The stuff is easily found and at a "reasonable" price if you have the time.
The hardest is the R134A because it is forbidden for a person who has no certificate, to use gas fridge.

[Christophe]

I am in the humbug!

You're not the only one !!

The stuff is easily found and at a "reasonable" price if you have the time.
The hardest is the R134A because it is forbidden for a person who has no certificate, to use gas fridge.

Business is business ... so grosso merdo if we follow you there is an industrial margin of 5 to 10 on thermodynamic water heater?

Because of their high price (and complexity = reliability?), I have always considered thermodynamic water heater as a humbug see:
https://www.econologie.com/forums/chauffe-ea ... t9236.html
et
www.econologie.com/forums/ thermodynamic-heating-t11015.html

Ah well here I knew that you were not the only one in smoke

Your editing shows that we know much better than that! Bravo!

Not yet looked at the technical details ...

[chatelot16]

Hi,
the funny thing about all this is that I'm not a refrigerationist
I am in the humbug!

it's not funny: it proves that every time there is a strict regulation so called because of security or pollution, it makes a privilege some of which benefit to swindle everyone

there is a good solution to avoid the problem of purchase of refrigerant gases: use the R297 which is only propane very simple

and it's not uncommon: just look at the labels of the fridge and recent freezer
R297 = propane
R600a = isobutane

in addition with these gases it is no longer essential to do everything in copper ... there is no corrosion in case of moisture in the gas

the propane dissolves a little in the oil and decreases its viscosity just change the compressor oil, to put a simple mineral oil, a little thicker

on the site of Bitzer, a manufacturer of compressur fridge it gives information on the choice of the oil to use the propane in their compressor standard

[dede021385]

I could use propane R290 (I use it before in my chiller) the problem is that on an installation like mine you to several hundred liters of gas, so in case of leakage, the house becomes a time bomb .
It is not for nothing that this gas is only used in refrigerators (load less than 100grs).
Large heat pumps are out of the question because of the risks.
Moreover at equal pressure, the R134A condenses 10 ° C higher.

[BobFuck]

Business is business ... so grosso merdo if we follow you there is an industrial margin of 5 to 10 on thermodynamic water heater?

Should compare with a thermodynamic group of the same power, roughly an air conditioning, which is for many, much cheaper ...

In addition it takes heat in the air, but where? in the House ? And winter?

[chatelot16]

in addition, I made a mistake ... it's good R290!

for a water heater there should not be much more gas than in a freezer

for larger machines such as heat pumps, pump out or in a well ventilated technical room such as a gas boiler, and use only water / water pumps so as not to run gas in long pipes.