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No hot water only luke warm?

Postby Keith1 » Wed Feb 13, 2013 10:21 am

Hi, I have luke warm water from cylinder. The hot water pipe leading into cylinder is hot and has a bleed valve on it, all other pipes out of cylinder our cold. The pipe leading out of the bottom of the cylinder has a drain off valve. I have replaced 3 way valve, boiler is 4 years old and had the system power flushed before boiler installed, cylinder is 9 years old, currently using emersion to provide hot water. Central heating all ok, all rads bled and bathroom rad is hot when hot water is on, boiler sarts if CH and also if CH/HW. I think that either the coil in the cylinder could be block with either sludge or air, I have pushed water through the system using a hose pipe with mains pressure via the outside drain off valve until it came out of the header tank, I have done 3 times but had no effect on cylinder. Any suggestions would be very much appreciated.
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Postby htg engineer » Thu Feb 14, 2013 4:17 pm

If the flow to the cylinder is hot but the return is cold then yes there's either a blockage or airlock in the coil.

I would drain the system, and undo the connections onto the coil in the cylinder. Check the fittings especially if they're elbows for blockages. You can then flush the coil out and check the flow/restrictions.

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Postby Trinity64 » Sat Feb 23, 2013 11:44 am

your electric shower uses cold water direct from the mains water and heats it independantly, so this will not affect the water in the bath.

What is the water at the other outlets like?.

What type of heating system do you have?

Hot water cylinder or commercial boiler ?

Combi Boiler heats hot water on demand, hot water cylinder keeps stored water at around 60-65 degrees heated from a regular boiler.

If it's a combi then it will need to be looked at by an engineer to work out what the problem is.

Hot water cylinder, could be that the cylinder thermostat has been accidentally turned down ( this is a small white thermostat near the bottom of the hot water cylinder) needs to be at 60-65 degrees (60 being appropriate for the scalding factor) this allows your boiler to heat the water to this temperature then switch off. If this is damaged then it could be that that is not allowing this to work properly.

Is the water heated by immersion heater, which is also located on the hot water cylinder via electrical switched spur.

Anymore information would be apprecited and i can help you further.

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Postby htg engineer » Sat Feb 23, 2013 7:07 pm

@trinity, have you mixed posts up? He has already said he has a cylinder, is using an immersion theater the water and he didn't mention a shower. Cylinder/tank stats don't have a colour standard, different manufacturers and different models can be different colours.

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