Adding a Calorifier - Already Have a Morco

[alan_fincher]

Currently our sole water heating is provided by a Morco instantaneous heater.

 

As we have a water cooled engine, I'd like to use heat that is currently just being dumped to the skin tank to run a calorifier.

 

I've looked at some previous threads, which have been most useful, but would ask people to repeat their thoughts on 2 specific topics.

 

1) I've tended to hear that horizontal calorifiers do not work quite as well as vertical ones. However, whilst we would struggle to accommodate a vertical one, finding space under a bed for horizontal should present no problems.

 

What are the issues, if using horizontal, and any special steps to take to make as efficient as possible, please ?

 

2) We would like to continue to have the option of the Morco, (for when not running the engine, or when calorifier has no more "hot"). Obviously we only have one hot feed to all taps and showers, so how is it best to arrange for a choice of hot water sources, calorifier or Morco, as appropriate ? Just a manual valve, or is a more automated arrangement that will switch to Morco if no "hot" in the calorifier possible, please ?

[Guest]

Currently our sole water heating is provided by a Morco instantaneous heater.

 

As we have a water cooled engine, I'd like to use heat that is currently just being dumped to the skin tank to run a calorifier.

 

I've looked at some previous threads, which have been most useful, but would ask people to repeat their thoughts on 2 specific topics.

 

1) I've tended to hear that horizontal calorifiers do not work quite as well as vertical ones. However, whilst we would struggle to accommodate a vertical one, finding space under a bed for horizontal should present no problems.

 

What are the issues, if using horizontal, and any special steps to take to make as efficient as possible, please ?

 

2) We would like to continue to have the option of the Morco, (for when not running the engine, or when calorifier has no more "hot"). Obviously we only have one hot feed to all taps and showers, so how is it best to arrange for a choice of hot water sources, calorifier or Morco, as appropriate ? Just a manual valve, or is a more automated arrangement that will switch to Morco if no "hot" in the calorifier possible, please ?

I have the same idea as yourself but in reverse-we have the calorifier but not the Morco.

Ours is a horizontal one (twin coil) fitted under the bed and is very good. It has surprised me how long the water remains hot. We did the following when installing it:

 

Skin fitting from pressure relief valve allows expansion overboard (have only ever seen a few dribbles).

Non-return valve into cold inlet.

22mm copper feeds from engine (long run) these also make efficient heaters in utility area.

Copper pipes are slightly higher than engine then run slightly uphill away from engine. This appears to stop hot water gravitying back through engine header tank.

Bleed valves in flow and return at highest point (a Godsend when we comissioned it)

The only way I can think of incorporating a Morco safely is to use a changeover valve as you suggest.

It will be interesting to see if there are any other ideas.

Edited December 19, 2005 by Guest

[DaveR]

Alan,

 

I had a horizontal tank and I gave up on it and have now fitted a vertical 50 litre job.

 

The problems I had :

 

1) the horizontal tank was above the engine and so was constantly air locked, I just couldn't bleed the system to get the engine cooling water to circulate.

2) with the tank being horizontal, it is difficult to get the full amount of hot water out, there seemed to be a lot of mixing of the incoming cold water which resulted in a quick blast of hot water followed by some luke warm & tepid stuff. I found that after a number of hours cruising there was enough hot water for a single shower - even then it was going cool at the end.

3) the tank had to be flushed every year as the sediment in the bottom would build up and discolour the water.

 

The vertical 50 litre tank cost me £175 and I made the mistake of only fitting a single coil job. As I am now looking to replace the stove with a Morso and back boiler I am faced with another choice. The hot water lasts for two showers now. I also believe it is also worth while fitting an immersion heater easier to do it now rather than later and gives you another option if you have mains power available.

 

The vertical tank warms up very quickly as I have located the tank right beside the engine. I must fit a valve to stop the hot water re-circulating through the engine block over night.

 

There is a firm near Nottingham who will do tanks to order, so if you have an odd size they can help out. However i have no idea on prices. I will dig around and see if I can find their literature for you.

[Keeping Up]

I also believe it is also worth while fitting an immersion heater easier to do it now rather than later and gives you another option if you have mains power available.

Do you know if you can get low-power immersion heaters? I wanted to fit one too, but all the ones I could find would have tripped the 10 Amp breaker on my shore supply.

[Guest]

Do you know if you can get low-power immersion heaters? I wanted to fit one too, but all the ones I could find would have tripped the 10 Amp breaker on my shore supply.

I think the one in ours is 1Kw (about 4 amps) but I would have to confirm that. Came with calorifier from Midland Chandlers.

[DHutch]

We have a twincoil calorifier, and a paloma (very like the the morco)

 

The way we have it set up is with the two units in paralell, with a valve on the two cold water feeds. So you just close one and open the other two swap between them.

 

The two coils of the (horizontal) calorifier are powered my the morso's back boiler (along with two rads) or steam from the boiler.

- And then if this runs out, or we not in steam and dont have the stove lit, you can swap over the two ball valves and lit the paloma.

 

Im not sure if it would work, but maybe you could have them in serise, with the calorifier first, and the paloma after, which could be lit all the time, just adding as much heat as nessary depending on the temp of the feed water (from the cal)

- Or do they get stropy about hot/warm feeds?

 

 

Dainel

[Big COL]

Currently our sole water heating is provided by a Morco instantaneous heater.

 

As we have a water cooled engine, I'd like to use heat that is currently just being dumped to the skin tank to run a calorifier.

 

I've looked at some previous threads, which have been most useful, but would ask people to repeat their thoughts on 2 specific topics.

 

1) I've tended to hear that horizontal calorifiers do not work quite as well as vertical ones. However, whilst we would struggle to accommodate a vertical one, finding space under a bed for horizontal should present no problems.

 

What are the issues, if using horizontal, and any special steps to take to make as efficient as possible, please ?

 

2) We would like to continue to have the option of the Morco, (for when not running the engine, or when calorifier has no more "hot"). Obviously we only have one hot feed to all taps and showers, so how is it best to arrange for a choice of hot water sources, calorifier or Morco, as appropriate ? Just a manual valve, or is a more automated arrangement that will switch to Morco if no "hot" in the calorifier possible, please ?

 

 

Alan

 

The choice of calorifier is yours to make considering the ease of installation, I have never had problems with air locks on horizontal calorifiers and if there was a problem with air locking then an auto air bleed would soon overcome it.

If you want to be fully automatic with hot water source then you can use a tank stat to control two mag valves one positioned on the hot water outlet of the calorifier and the other on the hot water outlet of the morco. The tank stat will open one valve and close the other and visa versa. If the water is not hot enough in the calorifier then the stat will have the mag valve closed on the calorifier and open on the morco, once the water reaches temp in the calorifier the tank stat will then close the mag valve on the morco outlet and open the mag valve on the calorifier outlet.

[Wolfy Smyth]

We have a twincoil calorifier, and a paloma (very like the the morco)

 

The way we have it set up is with the two units in paralell, with a valve on the two cold water feeds. So you just close one and open the other two swap between them.

 

The two coils of the (horizontal) calorifier are powered my the morso's back boiler (along with two rads) or steam from the boiler.

- And then if this runs out, or we not in steam and dont have the stove lit, you can swap over the two ball valves and lit the paloma.

 

Im not sure if it would work, but maybe you could have them in serise, with the calorifier first, and the paloma after, which could be lit all the time, just adding as much heat as nessary depending on the temp of the feed water (from the cal)

- Or do they get stropy about hot/warm feeds?

Dainel

My understanding of instantaneous heaters is that they must have cold supply at all times. I was going to go down that very same route until I read that.

Re 1Kw immersion heaters. they are available in most chandlers at about £30.00. They used to fit 750w immersions but these have been replaced by the 1Kw version. Available in several different lengths.

Re calorifiers. My calorifier is horizontal and I can get one bath and two showers out of it before it goes cold.

 

Steve

Edited December 21, 2005 by Wolfy Smyth

[alan_fincher]

My understanding of instantaneous heaters is that they must have cold supply at all times. I was going to go down that very same route until I read that.

 

Yes, but if you put valves in the OUTLET from the Morco, which is what I think Big Col is suggesting, then I don't think you are in danger of starving the Morco of water whilst it's turned on.

 

Surely it's just the same as current arrangements are for 99% of the time, when all hot taps are turned off ?

 

My calorifier is horizontal and I can get one bath and two showers out of it before it goes cold.

 

Steve

 

That sounds encouraging -

So far only DaveR seems to have voted against horizontal.

 

I will do a bit of studying when I next can to see exactly what size horizontal tank I could accomodate, and to what degree it's coils might be higher than the engine, leading to possible air locks.

 

And Colin....

 

Thanks for the additional PM you have sent me - most helpful, and I'll reply on that soon.