In hot water

plumbob

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Having recently tripled the size of our hot water tank (calorifier) I find I now have lots of very hot water indeed. Now, in my job , I have acess to any type of plumbing gear there is, BUT , if the water is heated via the engine, how can I control the temperature ? I have also changed the stats to new 85 degree ones , so now the water does indeed get to that sort of temperature.
There is a device known as a TMV ( thermostatic mixing valve), which takes hot in one port, cold in the other and produces approx 45C at the outlet. These are now to be fitted to every new home and to all major refurbs.

45C is not that hot, so does anyone use a different type of control over their hot water system that I dont know of ?? Is there a valve that people fit to the engine hoses ?? It dont seem possible to get lower temp engine stats, and would they be warm enough for the engines?
The TMV , as it mixes outside a contained environment, will not promote the growth of legionella, which at 85C will already have become a paella anyway.

Can anyone advise please.
 
if you introduce a plain bib/gate valve and reduce the flow through the calorifier, that would decrease the heat you are putting into it without using expensive mixer systems or thermostats.

Then if - for any reason you don't want any hot water, shut the valve completely ?
 
Putting a valve in the engine circuit will not control the temperature, only the time it takes to heat up the water.

Being of a generation where we are used to adapt, (or is it perhaps not wanting to add complications), we just take care. Extra pipes / junctions are a pin in a restricted area.

That's not cool nowadays, so how about this one?

Looks that is the job it is supposed to do - I note that new LTTTs have valves fitted nowadays, parallelling what has to be done in houses, but do ring them up - the Braunston branch is the most knowledgeable, and I think they're open today till 4. They do mail order from Penkridge.

Be aware that the valve introduces yet another restriction in the circuit, reducing what is already an indifferent flow on boats.
 
Could a valve like this be used to control the flow through the calorifier circuit? If connected in the return circuit between the outlet of the calorifier and the engine it would enable the maximum temp of the hot water to be controlled.

http://heating.consumers.danfoss.com/PCMPDF/VDTGO302_FJVR.pdf

Graham

Thanks, it could indeed possibly , do the job. Then of course, you would have to weigh up the possibly increased heat up time. That said, we normally have a tank full in about an hours running.
I have gone down the safest route , I have mixers on sink and shower and 2 ruddy great labels warning of very hot water at high pressure ( we arent sole users and have a 4 year old grandaughter ).
I may try the TMV blending valve first, mainly as I have a couple spare.
I will report my findings.
Thanks all.
 
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