TopBanana
Well-Known Member
Does it matter whether it flows up or down through the coil?
Immersion coolant flow direction
- Thread starter TopBanana
- Start date
PaulRainbow
Well-Known Member
No.
ChromeDome
Well-Known Member
Not if connected correctly.
If you tap into the engine coolant ‘wrong’ side of the thermostat, no heating of water will happen until the thermostat opens.
If you tap into the engine coolant ‘wrong’ side of the thermostat, no heating of water will happen until the thermostat opens.
TopBanana
Well-Known Member
Thanks
jwfrary
Well-Known Member
One might argue that's desirable as it would be better for the engine to reach operating temperature first prior to essentialy overcooling heating your water.
In practice its probably just less convenient and the effects are minimal.
Jmc1764
Well-Known Member
Hot in the bottom out at the top....logic says that this way the calorifier will heat more evenly, rather than super hot at the top and warm at the bottom. But in reality probably does not make much difference. But ensure your water gets over 50oC if you have a shower on board, you would not want to get legionella 
VicS
Well-Known Member
In at the top , out from the bottom.
This is the way any indirect domestic hot water system will be connected to the boiler.
You will quickly get hot water available for use at the taps whereas if you connect the other way round you will not get really hot water until the whole calorifier tank has heated through..
PaulRainbow
Well-Known Member
You appear to have stumbled into the wrong forum, this is PBO, not plumbers are us.
ChromeDome
Well-Known Member
I have a Sigmar calorifier and the connection of water circuits is clearly marked on the 2+2 in- and outlets.
The installation manual is clear on allowed installation angles too: "Universal mount (vertical and horizontal)".
Of my two engines one is providing hot coolant to the calorifier coil, from a drain plug low on the engine block. The rather low amount in the coil and its transfer of heat to the fresh water does not affect the engine temperature between the two engines, as they raise at same rate until normal working temperature.
I'm certain other setups will work - this works flawlessly also after draining/winterization/filling.
Hot water at the tap is very hot. Nice as you'd blend in a lot of cold water (use lee of the heated) for most uses. To mitigate the risk of someone getting burned, our tap has a blend valve that we normally keep at the desired temp.
The installation manual is clear on allowed installation angles too: "Universal mount (vertical and horizontal)".
Of my two engines one is providing hot coolant to the calorifier coil, from a drain plug low on the engine block. The rather low amount in the coil and its transfer of heat to the fresh water does not affect the engine temperature between the two engines, as they raise at same rate until normal working temperature.
I'm certain other setups will work - this works flawlessly also after draining/winterization/filling.
Hot water at the tap is very hot. Nice as you'd blend in a lot of cold water (use lee of the heated) for most uses. To mitigate the risk of someone getting burned, our tap has a blend valve that we normally keep at the desired temp.
Dragon461
Active Member
Yes, I realise that it's a pumped system on older gravity systems always hot at the top as it cools it is returned cooler and you heat the water at the top of the tank which is drawn off first.
Howerev in boats the cylinder lies horizontal and possibly this alters the effect.
PaulRainbow
Well-Known Member
The temperature of an engine supplying a calorifier is still regulated by the engine thermostat, so both engines will heat up at the same rate as normal, until the thermostat opens, at which time some coolant is allowed to flow through the calorifier coil. If, in doing so, the coolant temperature drops below the thermostat set point, it will close again. Assuming that the calorifier is correctly installed.
Most current calorifiers are fitted with a thermostatic valve at the hot outlet. You can have the water in the calorifier at a very hot temperature (it usually is when running the engine) but the water at the taps cannot exceed the temperature that the valve is set to.
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superheat6k
Well-Known Member
There is not a lot of impetus to the flow and anyway flow through any heat exchanger should be counterflow for best effect, so the hottest coolant at the high point will naturally sink downhill by convective flow, where it will meet the hottest water at the higher point in the calorifier. Then as it descends through the coil it will meet the cooler water further down.
The cooler water outside the coil will naturally percolate upwards providing a good mixing within.
So for these two reasons in at the top and out at the bottom - IMHO of course, although I deal with and design use of very large convective flow heat exchange vessels as part of my day job.
The cooler water outside the coil will naturally percolate upwards providing a good mixing within.
So for these two reasons in at the top and out at the bottom - IMHO of course, although I deal with and design use of very large convective flow heat exchange vessels as part of my day job.
superheat6k
Well-Known Member
Certainly heating the water close to engine coolant temperature say ~ 80 - 90oC could be potentially dangerous, but if you then introduce a thermostatic reg valve the result is say 15 litres of water in the calorifier at 80oC becomes perhaps 20 - 25 litres at 55oC, so far longer in the shower.
PaulRainbow
Well-Known Member
Boater Sam
Well-Known Member
If it is pumped by the engine, in at the bottom out at the top will enable easy self bleeding of air from the coil and will be approx 4% more efficient at heating the calorifier water.
Gravity circuits have to be the other way round.
Gravity circuits have to be the other way round.
PaulRainbow
Well-Known Member
What make/model of calorifier are you fitting ?
