Gravity circulation through Thermotop C

[plumbob]

Hi I am a new member with a 2004 not so new boat.

When i have been cruising the calorifier gets hot from the engine as expected (it is mounted in the engine bay). If i use very little water in the evening by the morning it has cold down considerably. This weekend i heated it with the thermotop c, got nice and hot and the flow and return pipes to the engine were cold so no gravity circulation there, however the thermotop was still hot and hour later. The flow pipe from the ttc is at the same level as the to flow pipe into the clarifier and the return is lower down. I am a heating engineer and my experience is telling me there is reverse gravity circulation through the ttc. My question to forumt is, has anyone else had this issue? The easy fix is to put a U shaped loop between the calorifier and the TTC or a clack valve. As the clarifier is effectively outside there will be a reasonable loss of heat into the engine bay but it seemed excessive to me.

[Boater Sam]

You have eliminated any gravity circ through the calorifier so it must be through the ttc which is most likely as you say because there is no loop to stop circulation.

I would put a downward loop in the flow pipe if that is feasible. An upward loop would work but you may have an air lock problem then.

Non return valves, even clack, may not be a good idea with the ttc, the circulator is very small as it is.

[plumbob]

Thank you for your input i will alter the pipe work and see what happens.

 

 

[LadyG]

3 hours ago, plumbob said:

Thank you for your input i will alter the pipe work and see what happens.

 

 

That sort of reminds me, a few weeks ago we had a new boater as in complete newby: we got the engine started 

and stopped.

Then he was going to do something electrical ........ has he ever been back?

Edited March 28, 2019 by LadyG

[dor]

Not quite sure what a 'clack' valve is, but I have in the past used a flap valve.  Sprung NRVs take quite a bit of pressure to open but the flap valve offers virtually no resistance.

 

ETA:  I see from Google that a clack valve is in fact a flap valve.

Edited March 28, 2019 by dor

[MtB]

 

I don't even understand the question....

 

 

But I'm FEEK, as any fule kno......

[LadyG]

5 minutes ago, Mike the Boilerman said:

 

I don't even understand the question....

 

 

But I'm FEEK, as any fule kno......

As long as it's not wiffin yer compass Mike, we don't expect miracles , but is one old boiler not the same as another? ?

 

 

 

[incoming]?

Edited March 28, 2019 by LadyG

[MtB]

6 minutes ago, LadyG said:

As long as it's not wiffin yer compass Mike, we don't expect miracles , but is one old boiler not the same as another? ?

 

 

 

[incoming]?

 

Qué?

 

 

[plumbob]

Clack, flap i have only been a heating engineer for 30 odd years, i cant be expected to remember the name of these things after only being in the trade that long. Having thought about it further i dont think i have ever fitted one in those 30 years. iI prefer the loop method as other than air lock it won't go wrong or stick and we all know if it can go wrong it will do but it will save it until the very worst time then go wrong.

 

Thank you all for your input