dan
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Posts: 31
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Post by dan on Oct 24, 2014 14:31:12 GMT
On our 2007 42i the hoy water system is playing up.
Whist running the water off, the temperature is not stable. This is especially noticeable in the shower, as you are very near to being scalded.
It seems that whilst the pump is dropped out the hot water gets hotter and hotter until the pump kicks back in again then it cools down to a more manageable temp, then as the pump drops out the water gets hotter again, and so it continues.
[/font]We have the 40l Quick water heater.
The same thing happens weather the water is heated by shore power or off the engine.
Any ideas welcome.
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Post by Tafika II on Oct 24, 2014 15:15:27 GMT
Sounds more like a pump problem than the water heater. When we ru the shower, the pump is on all of the time while the water is turned on, so it gets the proper mix of cold & hot. It sounds as if your pumps shuts off (rests) and the the pressure from just the hot water comes through and no mixing. What happens at the faucets?
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dan
Full Member
Posts: 31
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Post by dan on Oct 24, 2014 15:21:15 GMT
Hi Again!
The same thing happens but not as noticeable.
when the galley tap is run , the pump runs continuously, when the shower runs, the pump kicks in and out.
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Post by electricmonk on Oct 24, 2014 21:02:21 GMT
what you describe is a problem with the accumulator, the shower is a restricted flow so the pump being capable of supplying more than is needed cycles, when the galley tap is on the pump cant keep up so it stays on. The accumulator needs to be recharged.
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Post by nornaj on Oct 25, 2014 3:29:49 GMT
Agree that the problem is probably the accumulator loss of pressure.
Additional air should help - but for how long?
A replacement accumulator is more expensive than a variable speed FW pump.
Anyone out there installed such a pump? And how has it worked out?
best
Norna J
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dan
Full Member
Posts: 31
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Post by dan on Oct 25, 2014 5:09:55 GMT
What should the pressure be in the accumulator?
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Post by electricmonk on Oct 25, 2014 7:14:06 GMT
a new accumulator costs around £25 or it should.
the pressure in the accumulator is best adjusted by trial and error (IMHE). What you must do is get all the water out of the accumulator to start. This is best achieved by turning off the water-pump and opening a tap - any tap. next attach a pump to the valve on the accumulator and introduce some air - water should come out of the tap. In my experience you are not looking for a lot of pressure, 3 - 5 psi works for me (the water pump will provide the rest). Keep the tap open and the small amount of pressure on until no more water comes out of the tap - should be about 8 litres if the accumulator is full of water. The valve on top of the accumulator is the same as a car tyre valve and can be changed in the same way - now is a good time to change it.
With a new valve fitted try just a couple of pumps with bicycle tyre pump then remove the air pump, turn off the tap and turn on the water-pump, the pump should run for about 15 - 20 seconds as pressure is stored in the accumulator. When you turn on the tap water should flow for about 20 seconds before the pump comes on, job done.
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Post by sailbleu on Oct 25, 2014 7:37:32 GMT
Did you install a new shower head/spray recently ?
Was the problem always there ?
Remember some sprayheads need a minimum of pressure to work properly , maybe a funny behavior of the spray translates into an imbalance of hot and cold supply.
Also check for debri in the tap filter(s) , when the pump swtches on and off while taking a shower that indicates an obstruction somewhere.
I would think , but could be mistaken of course , it is not the accumulator .
Off topîc , some years ago I installed a thermostatic faucet , I strongly recommend this to everyone.
It saves you a lot of water adjusting the showertemp in the beginning and prevents supprises during showers when the boiler runs short of warm water
Regards
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Post by electricmonk on Oct 25, 2014 12:25:04 GMT
Did you install a new shower head/spray recently ? Was the problem always there ? Remember some sprayheads need a minimum of pressure to work properly , maybe a funny behavior of the spray translates into an imbalance of hot and cold supply. Also check for debri in the tap filter(s) , when the pump swtches on and off while taking a shower that indicates an obstruction somewhere. I would think , but could be mistaken of course , it is not the accumulator . Off topîc , some years ago I installed a thermostatic faucet , I strongly recommend this to everyone. It saves you a lot of water adjusting the showertemp in the beginning and prevents supprises during showers when the boiler runs short of warm water Regards Yes but the situation is the same if he uses a tap, so the problem isn't the shower head though showers are more susceptible to pressure drops as in this case, the problem is the pump and/or the accumulator. Obstructions would be easy to spot as there would be a reduction in flow, accumulator problems are very common, some "marine engineers" don't know how to set them up! the Jeanneau instructions for my SO37 were completely wrong and resulted in the pump coming on every time a tap was opened, (the engineer claimed that was how it was supposed to work - he was re-educated) he had effectively removed the accumulator - the instructions said, "pressurise the water system then vent all the air from the accumulator valve". I rest my case. |
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