Calorifier maintenance

[Overandunder]

Hi all. I recently posted asking a few basic calorifier questions (which is a new feature to me, the used AWB I bought earlier this year has a factory installed one).

I have a lot of documentation for nearly all the boats equipment - but nothing for that unfortunately. Having just emptied the cockpit locker to finally access it - I can't see any manufacturers label to be able to Google very much either.

The unit is much larger than I was expecting - it's roughly the size of a beer barrel. It sits in the corner of the locker formed by the heads bulkhead to one side (no access) and the engine compartment partition (again no access).

The pipework to and from the engine I can access however from the back of the engine - so would that be the only way of draining it ? Perhaps answering my own question !?

Also how should the PRV take off pipe be routed ? At the moment it's attached to a clear piece of pipe just led loosely into the cockpit locker (which doesn't seem right at all).

One last please - should the black rubber pipes to and from the engine that supplies it be insulated - or really no point ?

Thanks for any replies / tips and advice.

 

[Plum]

Hi all. I recently posted asking a few basic calorifier questions (which is a new feature to me, the used AWB I bought earlier this year has a factory installed one).

I have a lot of documentation for nearly all the boats equipment - but nothing for that unfortunately. Having just emptied the cockpit locker to finally access it - I can't see any manufacturers label to be able to Google very much either.

The unit is much larger than I was expecting - it's roughly the size of a beer barrel. It sits in the corner of the locker formed by the heads bulkhead to one side (no access) and the engine compartment partition (again no access).

The pipework to and from the engine I can access however from the back of the engine - so would that be the only way of draining it ? Perhaps answering my own question !?

Also how should the PRV take off pipe be routed ? At the moment it's attached to a clear piece of pipe just led loosely into the cockpit locker (which doesn't seem right at all).

One last please - should the black rubber pipes to and from the engine that supplies it be insulated - or really no point ?

Thanks for any replies / tips and advice.

I assume your engine is indirectly cooled with a heat exchanger so the " coolant" from-to the engine contains the correct "antifreeze" therefore that part needs no maintenance or draining. No point in insulating those black hoses unless they are very long. You need to be able to inspect them for chaffing.

The clear hose from the PRV is often just run into the bilge by boatbuilders but not ideal (its the cheapest option! ). I run mine into a 1litre plastic bottle and empty it occasionally.

Unless you are in a country where sub zero temperature never happen then you definetly need to locate a way of draining the fresh water. Mine has a drain tap specifically for this.

Also, I added extra insulation to the whole calorifier which made a big difference to the retained heat the following morning for a shower.

 

[vyv_cox]

The importance of ensuring that the engine antifreeze is kept in good condition cannot be over-emphasized. I know of several calorifiers whose coils corroded through due to poor coolant condition. The coil could not be repaired so the calorifier was scrap. There can be quite a mixture of metals here for which good inhibitor is essential.

 

[Caladh]

I assume your engine is indirectly cooled with a heat exchanger so the " coolant" from-to the engine contains the correct "antifreeze" therefore that part needs no maintenance or draining. No point in insulating those black hoses unless they are very long. You need to be able to inspect them for chaffing.

The clear hose from the PRV is often just run into the bilge by boatbuilders but not ideal (its the cheapest option! ). I run mine into a 1litre plastic bottle and empty it occasionally.

Unless you are in a country where sub zero temperature never happen then you definetly need to locate a way of draining the fresh water. Mine has a drain tap specifically for this.

Also, I added extra insulation to the whole calorifier which made a big difference to the retained heat the following morning for a shower.

I also drain the PRV to an old bottle in the bilge. Can’t remember ever actually having any water in it. I’d be interested in what extra insulation you put around your cylinder ?

 

[Overandunder]

I assume your engine is indirectly cooled with a heat exchanger so the " coolant" from-to the engine contains the correct "antifreeze" therefore that part needs no maintenance or draining. No point in insulating those black hoses unless they are very long. You need to be able to inspect them for chaffing.

The clear hose from the PRV is often just run into the bilge by boatbuilders but not ideal (its the cheapest option! ). I run mine into a 1litre plastic bottle and empty it occasionally.

Unless you are in a country where sub zero temperature never happen then you definetly need to locate a way of draining the fresh water. Mine has a drain tap specifically for this.

Also, I added extra insulation to the whole calorifier which made a big difference to the retained heat the following morning for a shower.

Thanks - yes I have fw cooled engine. One of my tasks this winter is to remove and descale the heat exchanger and replace the a/f mixture. Salt water pump had signs of a leak past the water seal so I've already stripped and rebuilt it.

Thinking again about the safety PRV line I was thinking of perhaps tee ing this in to one of the overboard drain hoses (which all leave from the starboard qtr which are the same side as the locker anyway). Any drawback to this - it would be a slightly 'uphill' route but if the pressure was getting high enough the water would still have an escape route ?

 

[rogerthebodger]

On my Calorifier the PRV is piped into the engine anti-siphon valve skin fitting and both work together OK

 

[Plum]

Thanks - yes I have fw cooled engine. One of my tasks this winter is to remove and descale the heat exchanger and replace the a/f mixture. Salt water pump had signs of a leak past the water seal so I've already stripped and rebuilt it.

Thinking again about the safety PRV line I was thinking of perhaps tee ing this in to one of the overboard drain hoses (which all leave from the starboard qtr which are the same side as the locker anyway). Any drawback to this - it would be a slightly 'uphill' route but if the pressure was getting high enough the water would still have an escape route ?

Depends what that overboard drain hose does. Bilge pump?

 

[PeterBoater]

If the PRV is the type that has a knurled plastic knob, you should turn it at least once a year. I think about one quarter turn (can't remember which way) until it 'clicks'; apparently it stops the thing seizing up.

 

[Plum]

I also drain the PRV to an old bottle in the bilge. Can’t remember ever actually having any water in it. I’d be interested in what extra insulation you put around your cylinder ?

My "cylinder" is actually encased in a metal box which I cannot easily remove to see what the original insulation is like. I have added 50mm of Celotex type insulation board on top, two old polyester fibre pillows insulate two sides and the back (at least 50mm thick), 13mm of expanded foam bonded to the front face (tricky due to all the fittings) and the whole lot sits on a sheet of plywood.

 

[Plum]

Thanks - yes I have fw cooled engine. One of my tasks this winter is to remove and descale the heat exchanger and replace the a/f mixture. Salt water pump had signs of a leak past the water seal so I've already stripped and rebuilt it.

Thinking again about the safety PRV line I was thinking of perhaps tee ing this in to one of the overboard drain hoses (which all leave from the starboard qtr which are the same side as the locker anyway). Any drawback to this - it would be a slightly 'uphill' route but if the pressure was getting high enough the water would still have an escape route ?

my drain tap is near the bottom left corner in this picture: