webasto to run heating and hot water

[Alantw]

Hello,

        I have a Wesbasto C fitted in my boat, it has been there for a number of years piped to two rads one 3ft one 2ft when i got it running it was noisy after a while it was not making as much noise ,so it works fine.Can i plumb this to run the clorifier as well as running throgh my B.M.C 1.5 engine as it is the engine heats the clorifier [60 lts] and wesbasto runs two radiators seems a waste of power, heat and fuel .

                                                                                                  Any ideason this

                                                                                                                    many thanks Alantw

[Tracy D'arth]

You would need a twin coil calorifier or some sort of heat exchanger as the water in the engine system is not the same as is in your radiator system.

You have a header tank for the heating probably and a radiator cap on the engine exhaust manifold? You cannot connect them together.

[Alantw]

Yes very good point,did not think of that.

                                                         Thanks Alantw

[ditchcrawler]

When we had or share boat somehow the Ebberspature was set up so that the engine cooling and theEbber went through the radiators, dont ask me how but you could switch the pump on while cruising.

[cuthound]

32 minutes ago, ditchcrawler said:

When we had or share boat somehow the Ebberspature was set up so that the engine cooling and theEbber went through the radiators, dont ask me how but you could switch the pump on while cruising.

 

If you had to switch a separate pump on to get hot radiators from the engine, they were probably using the calorifier as a crude heat exchanger.

 

My boat has this arrangement, and whilst the radiators get warm with the second pump in the HW circuit switched on, they are nowhere near as hot as with the Webasto on. A proper plate heat exchanger does a better job.

 

The other alternative is that the calorifier coils are plumbed incorrectly in series.

 

I had this when I bought my boat and the engine coolant was circulating through both calorifier coils, the Webasto and the radiators whenever the engine was running. ?

[Tony Brooks]

1 hour ago, Alantw said:

Hello,

        I have a Wesbasto C fitted in my boat, it has been there for a number of years piped to two rads one 3ft one 2ft when i got it running it was noisy after a while it was not making as much noise ,so it works fine.Can i plumb this to run the clorifier as well as running throgh my B.M.C 1.5 engine as it is the engine heats the clorifier [60 lts] and wesbasto runs two radiators seems a waste of power, heat and fuel .

                                                                                                  Any ideason this

                                                                                                                    many thanks Alantw

If the engine cooling system and the Webasto are both sealed pressurised systems running at a similar pressure then I don't see why not apart from the 1.5 runner manifold blanking plugs tend to  fail/blow off at higher pressures.You would have to organise only one topping up point and that could prove difficult. If both are unpressurised open systems then as long as the two header tanks are at the same level then it should also work. However I think a plate heat exchanger is the way to go so you keep two totally septate systems - easier fault finding etc..

[Alantw]

.Hello Mr Brooks 

                         I have sat and thought i should be able to connect the two but as pointed out by Tracy'D'arth the engine side is presuised the Webasto just has a header tank join together and it wud blow out though the header tank,i just looked at it as two hot water systems,the idea of hot water use of both system woud be good to help one another but ,but, oh puff.Oh well at least i;ve learned that manifold blank plugs can blow out ,

                                                                                                   Many thanks for the input

                                                                                                                                                Alantw

                                                   

[Alantw]

Ah Mr Ditchcrawler

                                  that was my plan great idea but alas presuised system

[nb Innisfree]

Innisfree's LPWS4 ran unpressurised to enable CH and Mikuni to share the same circuit, IIRC when I sold her she had done about 7k hours with no problems, a combination of diverter and isolating valves allowed Mikuni to preheat engine (handy in cold weather) and/or CH, or engine to heat rads (6), engine coolant pump coped ok and kept boat toasty while on the move. Only possible downside was engine temp coolant in CH circuit, also large header tank to accommodate expansion of 5 to 6 galls coolant. (I utilised a length of plastic soil pipe mounted upright in a corner on the cruiser deck) 

Edited March 15, 2020 by nb Innisfree

[cuthound]

15 minutes ago, Alantw said:

Ah Mr Ditchcrawler

                                  that was my plan great idea but alas presuised system

 

In which case either put a seperate (to the Webasto central heating) pump on the central heating circuit and then either use the calorifier as a crude heat exchanger to give slightly warm radiators to take the chill off, or better still, then add a stainless steel plate heat exchanger off a domestic central heating boiler between the engine coolant circuit and the central heating circuit to give you piping hot radiators.

[ditchcrawler]

1 hour ago, cuthound said:

 

If you had to switch a separate pump on to get hot radiators from the engine, they were probably using the calorifier as a crude heat exchanger.

 

My boat has this arrangement, and whilst the radiators get warm with the second pump in the HW circuit switched on, they are nowhere near as hot as with the Webasto on. A proper plate heat exchanger does a better job.

 

The other alternative is that the calorifier coils are plumbed incorrectly in series.

 

I had this when I bought my boat and the engine coolant was circulating through both calorifier coils, the Webasto and the radiators whenever the engine was running. ?

I dont think so. I have that arrangement now for a single radiator at the front end of the accommodation from the top coil