Limescale build up on the fins of a cylinder coil

[communiverse]

Does anyone know how quickly limescale can build up on the external fins of a cylinder coil? The hardness of the water passing through the cylinder is not known, but is likely to be high in lime. The water is being drawn from a borehole. The symptom is that water is passing through the coil at the prescribed flow rate and delta T, but is not able to give up its heat into the cylinder. The heat source is a heat pump, circulation is 40 litres per minute, but the heat pump short cycles rapidly because it cannot lose its heat. The coil has a 5 sq m surface area. Thank you for any suggestions you can offer.

 

[Bronze_tap]

Does anyone know how quickly limescale can build up on the external fins of a cylinder coil? The hardness of the water passing through the cylinder is not known, but is likely to be high in lime. The water is being drawn from a borehole. The symptom is that water is passing through the coil at the prescribed flow rate and delta T, but is not able to give up its heat into the cylinder. The heat source is a heat pump, circulation is 40 litres per minute, but the heat pump short cycles rapidly because it cannot lose its heat. The coil has a 5 sq m surface area. Thank you for any suggestions you can offer.

And what is the tank temp setpoint? The lower it is, the longer it will last between descalling...

But if you set it <45, than make sure there are no users with compromised immune system or very old dudes using the shower.

Ideally peek into the tank with boroscope.

And get a big load of descaler+inhibitor ready...

 

[Mike Jackson]

And what is the tank temp setpoint? The lower it is, the longer it will last between descalling...

But if you set it <45, than make sure there are no users with compromised immune system or very old dudes using the shower.

Ideally peek into the tank with boroscope.

And get a big load of descaler+inhibitor ready...

Please stop giving dangerous advice. Hot water should be stored at 50 - 65 to prevent the build up of legionella bacteria. A correctly installed heat pump system will have a boost immersion that boosts the temp once a day to disinfect the system. The answer to lime scale prevention is some form of water treatment not storing the water at a dangerously low temperature.