Cylinder/calorifier cooling

[Glynn]

Our upright cylinder or calorifier is cooling down quicker than I think it should, it is factory insulated with the foam stuff.

It heats up very hot by either the immersion, webasto or the engine, just that it cools down too quick.

It is mounted vertically in the engine room of a wide beam cruiser stern boat.

Is it worth adding a cylinder jacket ?, any other suggestions ?.

Edited October 12, 2014 by Glynn

[Tony Brooks]

Is it thermo-syphoning round the engine coil and actually heating the engine or skin tank?

 

If it is try first re-routing the coil pipes so there is a horizontal length. Then try reversing them so the hot goes in the lower connection and if that does not work fit a flap type check valve but beware, depending upon the engine it could reduce the coolant flow and thus extend the heat up time.

[mango]

Is it thermo-syphoning round the engine coil and actually heating the engine or skin tank?

 

If it is try first re-routing the coil pipes so there is a horizontal length. Then try reversing them so the hot goes in the lower connection and if that does not work fit a flap type check valve but beware, depending upon the engine it could reduce the coolant flow and thus extend the heat up time.

I had this problem with the hot water tank in my house and fitted a motorised valve to shut off the flow except when the boiler was running. It made a huge difference and did not affect the time taken to heat the water.

[dor]

Had this on my last boat. Fitted a flap-valve and cured it.

[Tony Brooks]

I had this problem with the hot water tank in my house and fitted a motorised valve to shut off the flow except when the boiler was running. It made a huge difference and did not affect the time taken to heat the water.

 

The differences are that a motorised valve does not impede flow when it is in the "flow" position and most modern domestic boiler systems use a pump to circulate the water and that would open a flap valve.

 

On a boat the calorifier may be connected to the skin tank side of the engine thermostat and any restriction to flow is likely to make it more likely that the water will flow via the skin tank rather than the calorifier coil.

 

Not too many 12 volt motorised valves at reasonable cost as well.

[mango]

 

The differences are that a motorised valve does not impede flow when it is in the "flow" position and most modern domestic boiler systems use a pump to circulate the water and that would open a flap valve.

 

On a boat the calorifier may be connected to the skin tank side of the engine thermostat and any restriction to flow is likely to make it more likely that the water will flow via the skin tank rather than the calorifier coil.

 

Not too many 12 volt motorised valves at reasonable cost as well.

I have seen this done but it's better to feed the calorifier from the hot side of the thermostat, even if it means the engine takes longer to reach operating temperature.

 

Many boats have 230V systems these days, so a motorised valve could be an option.

[smileypete]

As well as unwanted themocycling, a surprising amount of heat can be lost through connecting pipes and immersion bosses, can do with decent insulation.

 

Also the calorifier coil is or the immersion heater is usually some way up, so over time the heat may even out, so the top gets cooler but no heat is 'lost' as such.

 

There's a Ford heater control valve available for £10ish on Ebay, might be good to help reduce overcooling of the engine and thermocycling, dunno what size hose it takes:

 

http://www.ebay.co.uk/itm/NEW-Ford-Heater-Control-Valve-High-Quality-Fits-Fiesta-Transit-KA-Puma-/191055239846

 

cheers, Pete.

~smpt~

Edited October 12, 2014 by smileypete

[ditchcrawler]

As well as unwanted themocycling, a surprising amount of heat can be lost through connecting pipes and immersion bosses, can do with decent insulation.

 

Also the calorifier coil is or the immersion heater is usually some way up, so over time the heat may even out, so the top gets cooler but no heat is 'lost' as such.

 

There's a Ford heater control valve available for £10ish on Ebay, might be good to help reduce overcooling of the engine and thermocycling, dunno what size hose it takes:

 

http://www.ebay.co.uk/itm/NEW-Ford-Heater-Control-Valve-High-Quality-Fits-Fiesta-Transit-KA-Puma-/191055239846

 

cheers, Pete.

~smpt~

Or a 12 volt solenoid valve http://www.ebay.co.uk/itm/Adafruit-Industries-Solenoid-Valve-Plastic-Water-12-Volt-997-/400583553395?pt=UK_Computing_Other_Computing_Networking&hash=item5d44a3f173

[Phil Ambrose]

MTB might be able to comment on insulating the immersion boss, I think it is a no-no but may well be wrong. Surcal claim that their calorifiers lose less than 1c an hour.

Phil

[mango]

Thanks for the information about 12V solenoid valves folks. That could be very useful to a friend.

[ditchcrawler]

Thanks for the information about 12V solenoid valves folks. That could be very useful to a friend.

You better show him this as well http://www.ebay.co.uk/itm/1pcs-Motorized-valve-brass-G1-1-4-DN32-reduce-port-2-way-12v-electric-valve-/121275681095?pt=UK_DIY_Materials_Plumbing_MJ&hash=item1c3c980947

[mango]

You better show him this as well http://www.ebay.co.uk/itm/1pcs-Motorized-valve-brass-G1-1-4-DN32-reduce-port-2-way-12v-electric-valve-/121275681095?pt=UK_DIY_Materials_Plumbing_MJ&hash=item1c3c980947

Thanks. I like the fact that it will stay open or closed without consuming power.

[Hawkmoth]

12 volt motorised valve. The best option. No current used unless it's actually moving.

http://www.ebay.co.uk/itm/3-4-DN20mm-Electric-Ball-Valve-Two-Way-Brass-Motorized-Ball-Valve-/251479798128?pt=UK_Home_Garden_Hearing_Cooling_Air&var=&hash=item3a8d5d3170

Edited October 12, 2014 by lyraboat

[Detling]

A solenoid valve which is energised when the engine is on will use "free" power from the alternator so will not have any effect on the batteries, It is also easily available UK threads, not US plumbing threads and is fairly fool proof.

[smileypete]

MTB might be able to comment on insulating the immersion boss, I think it is a no-no but may well be wrong. Surcal claim that their calorifiers lose less than 1c an hour.

Phil

 

Could measure the temp under the cap with a probe, I suspect it's pretty close to the cylinder temp, see pic below.

 

Looks like heat is lost around the edge of the boss, so just insulate and leave the cap uncovered if concerned:

 

 

http://www.greenbuildingforum.co.uk/forum114/comments.php?DiscussionID=9041

 

cheers, Pete.

~smpt~

Edited October 12, 2014 by smileypete