Morco Instantaneous Water Heater

[NB Alnwick]

Allan,

 

It is possible that the new expansion has had the same effect on the accumulator as when I ran the tap with the power off. Is the expansion tank pressurised to the same level as the water supply to the Morco? This is certainly the line of enquiry that I would be following - our Morco is the same age and probably the same model as yours and it is very sensitive to fluctuations or pulsations in the inlet water pressure.

 

We are now ice free (thank you for asking) and the boat is gently rocking in the wind without the nasty cracking noises that we had when iced in

 

Best Wishes,

Graham

[alan_fincher]

It is possible that the new expansion has had the same effect on the accumulator as when I ran the tap with the power off. Is the expansion tank pressurised to the same level as the water supply to the Morco? This is certainly the line of enquiry that I would be following - our Morco is the same age and probably the same model as yours and it is very sensitive to fluctuations or pulsations in the inlet water pressure.

The new expansion vessel was fitted a long while after the Morco woes began, so I don't think is anything to do with it. (In fact I've made virtually no attempt to sort out the Morco since it was added).

 

However the accumulator definitely has a question mark over it, so that's what I'll investigate next.

 

I've not been to the boat today, but am guessing most of the ice will now be gone. The thaw was working it's way down to us yesterday, with half the marina clear, but still significant ice around us. (It's rocking again though, so no longer held firm).

 

Alan

[Nb Harold]

The new expansion vessel was fitted a long while after the Morco woes began, so I don't think is anything to do with it. (In fact I've made virtually no attempt to sort out the Morco since it was added).

 

However the accumulator definitely has a question mark over it, so that's what I'll investigate next.

 

I've not been to the boat today, but am guessing most of the ice will now be gone. The thaw was working it's way down to us yesterday, with half the marina clear, but still significant ice around us. (It's rocking again though, so no longer held firm).

 

Alan

Hi

 

I suffered this problem just before christmas. Followed the low gas route with no success. Burner worked flat out (big roaring flame) still no hot water. Our Morco is about 3 years old. Stripped the water control valve found nothing wrong with it, but when reassembled heater worked fine. May not solve your problem but worth a look.

 

Allan

[alan_fincher]

Hi

 

I suffered this problem just before christmas. Followed the low gas route with no success. Burner worked flat out (big roaring flame) still no hot water. Our Morco is about 3 years old. Stripped the water control valve found nothing wrong with it, but when reassembled heater worked fine. May not solve your problem but worth a look.

 

Allan

Hi Allan,

 

Thanks for the input.

 

I've actually had all the water side of things apart, including replacing the diaphragm, (I wasn't convinced it was going to help, and it didn't ).

 

I was slightly optimistic when I found the pin that activates the gas was quite "sticky", but responded well to some silicone grease, that I might have found the problem. Sadly no.

 

Glad you got yours sorted though, (mine's a lot older BTW).

 

Alan

[NB Alnwick]

I am bumping Alan's topic because we are still having problems with our Morco D61E Instantaneous Water Heater:

 

Earlier in the year we found that the performance was quite poor with water coming out barely 'luke-warm' and the flow rate was quite poor. At the time we identified the possible cause as insufficient flow and pressure - so the water pump was replaced. After which the flow level improved and we seemed to be getting adequate hot water.

 

Recently, however, the water output has reverted to its earlier 'luke-warm' state (in fact it would be better to describe the output as cold) - with one major difference, the water pressure and flow rate through the Morco is better than ever! There seems to be nothing amiss with the burners - they burn fiercely with a nice blue flame - so I suspect that the problem is in the water control regulator which now appears as if it is not sufficiently restricting or altering the flow of water when the control knob is turned from its minimum to its maximum setting.

 

Has anyone had similar problems? And, if so, how have these been solved please?

 

A replacement 'Water Control Assembly' from Morco costs over £50!

[churchward]

I am bumping Alan's topic because we are still having problems with our Morco D61E Instantaneous Water Heater:

 

Earlier in the year we found that the performance was quite poor with water coming out barely 'luke-warm' and the flow rate was quite poor. At the time we identified the possible cause as insufficient flow and pressure - so the water pump was replaced. After which the flow level improved and we seemed to be getting adequate hot water.

 

Recently, however, the water output has reverted to its earlier 'luke-warm' state (in fact it would be better to describe the output as cold) - with one major difference, the water pressure and flow rate through the Morco is better than ever! There seems to be nothing amiss with the burners - they burn fiercely with a nice blue flame - so I suspect that the problem is in the water control regulator which now appears as if it is not sufficiently restricting or altering the flow of water when the control knob is turned from its minimum to its maximum setting.

 

Has anyone had similar problems? And, if so, how have these been solved please?

 

A replacement 'Water Control Assembly' from Morco costs over £50!

In my limited experience with these things (we have a D61B) it sounds like a water flow diaphragm issue. Possible frost damage? They are expensive to replace as you say.

[NB Alnwick]

In my limited experience with these things (we have a D61B) it sounds like a water flow diaphragm issue. Possible frost damage? They are expensive to replace as you say.

 

I don't think recent frost damage is likely as the heater is only a couple of yards from our Squirrel stove which hasn't been allowed to go out since October! However, there is always the chance that it may have suffered frost damage earlier in its eight year plus existence.

[churchward]

I don't think recent frost damage is likely as the heater is only a couple of yards from our Squirrel stove which hasn't been allowed to go out since October! However, there is always the chance that it may have suffered frost damage earlier in its eight year plus existence.

Ah yes I forgot you are on board most of the time! I guess it could just be a flaw/weakness in the diaphragm and the rubber has split/perished. I can remember if there is a valve there as well that could fail?

Edited February 18, 2010 by churchward

[RobinJ]

I did lubricate the sliding pin on the disc it presses on last time, with Silicone grease, but I'll check again that that is still moving freely.

 

I hadn't until recently seen that the manual says what the burner pressure should be - 36.3 mbar if running on propane.

 

I make that 14.6" WG, but when I tried to measure it back in October, down in London, only got about 13.6" WG, (so only about 33.9 mbar).

Hi Alan

 

I thumbed through the book and note they say maximum drop of 2.5mb (thats takes it to 34.5).

I also noted it mentioned something about a filter in the water inlet, you're obviously getting plenty of flow, do you think the water pressure is high enough to operate the gas valve fully?

Have you noticed any difference after its been on a couple of minutes?

[NB Alnwick]

Ah yes I forgot you are on board most of the time! I guess it could just be a flaw/weakness in the diaphragm and the rubber has split/perished. I can remember if there is a valve there as well that could fail?

 

This does seem logical - especially since we now seem to get a virtually unimpeded flow of water through the heater. I am not sure how the water flow control knob actually controls the flow - there seems to be a valve with a tapered seat held in place by a spring below the diaphragm but I cannot see how it is actuated.