Improving on TRV

[Mikefromlondon]

Trouble with domestic anaerobic toilets is one accidental dose of bleach or lavatory cleaner and the gas supply can end until the pot is cleared of the offending chemicals.

On a large scale it is far more robust.

http://www.geotechuk.com/products/applications/landfill-gas-field-management.aspx

I was thinking more along the lines of the internal conversion process and collection of the farts..

You are not far from it, one could rig a small pipe and a flint, and will never have to carry a cigarette lighter.

 

[DaveHerns]

I've always wanted to ignite one of my farts....
Going back to the original topic there's an advert somewhere for some "amazing new system" of electric radiators that you can turn on and off like an electric light . I'm sure you can but what about waiting while the room warms up?

 

[Mikefromlondon]

I remember making a thermostat control using just a normal silicon diode as the sensor, it was to replace a thermostat in a fridge, so i used a relay controlled by this little circuit which became so sensitive that as soon as you open the fridge door the relay would cut in within about a second, at first I suspected that the fridge light bulb coming on generated a spike that tripped the circuit on, so I tried suppressing for any spikes on my low voltage regulated power supply that supplied 12v dc to my circuit through a small transformer and regulator, but it still tripped each time you opened the fridge door, so then I tried another method to rule out that it wasn't definitely the bulb tripping the circuit on, so I took the bulb out, and it still tripped the relay, it was hyper sensitive, it did not have any hysteresis, but then I thought could the door switch also supply power to something else, so i eliminated this possibility by taping over the door contact switch, and again each time you open the door and more or less instantly the relay tripped in, the temperature control was hyper sensitive, so I had to enclose the diode sensor inside a plastic sleeve (heat shrink wrapping) so as to delay its thermal response, this stopped the relay coming on instantly and delayed it by about 10 seconds, but it still sensed an increase in temperature by a minute degree, so I then had to implement some hysteresis such that it won't trip on again until temperature rose by a full degree, so in other words 5a very closed loop feedback can also become nuisance and hence why TRVs do a reasonable job though their response could be shortened a little, so that occupants don't feel too cold for too long and nor too hot for too long.

 

[Agile]

Mike seems to have forgotten the obvious.

That's the same obvious as is involved in TRV control of rads.

That's the time constant of the heatup/cool down of rads. Conversely the cooldown/warm up of the fridge cabinet.

 

[Mikefromlondon]

Yes Tony, if you were incubating embryos , you need an oven with a very finite temperature control, I thought why not make a fridge with a finite control, what harm would it do? obviously no harm apart from being nuisance by having shorter on off cycles.

I don't suffer from a sudden cold spells if one opens a door even for a few minutes, cold air may gush in, but within a few short minutes temperature evens out as there is a huge thermal mass that has been build by keeping my house heated constantly at or around 21-22 c using a radiator flow temperature of no more than 35-45 degrees C. (Vaillant VCW221 can be taken down to 30C flow)

 

[flameport]

I thought why not make a fridge with a finite control, what harm would it do? obviously no harm apart from being nuisance by having shorter on off cycles.

Which will significantly shorten the life of the compressor and use more electricity, as motors use more power to start than they do when running.

There are good reasons why thermostats, TRVs and other devices work in the way they do - they have already been designed to be optimal for their particular application.

 

[Mikefromlondon]

Also note my CH does not require a Thermostat control since I run it 24/7 throughout winter months, this is because I believe i AM PROLONGING THE LIFE OF MY BOILER AS IT DOESN'T HAVE TO STOP AND START frequently which can draw more current on start up and so reduce the boiler life, yes you are right at last!

 

[Dan Robinson]

Guess we had better go round reducing the hysteresis on all our customer's kit that we've poorly installed over the years. What were we thinking?

 

[Dan Robinson]

Go on Mike. Pretend you're not reading my posts

 

[dilalio]

Are there any other "Mikes from London" or are you the only one?

 

[Mikefromlondon]

Are there any other "Mikes from London" or are you the only one?

I did not know you would act this stupid not to work that one out yourself.

 

[TCCHeating]

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And a witness too if you need pal