Worcester Heatslave CF 20/25

20 Jul 2009
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United Kingdom
Got very low hot water pressure at all the taps on the following Oil Fired boiler:

Worcester Heatslave CF 20/25

Any ideas

Thanks in advance
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OK, any ideas then as to why all of a sudden I have low hot water pressure (literally drippling out of all taps) yet the mains cold is fine?
You have low water 'flow'. Can be caused by faulty or blocked filters, HW heat exchanger or thermostatic blending valve (if you have one).
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OK so low 'flow' thanks for that, sounds like it is going to be a case of trial and error then by replacing certain parts. Presumably there is a flow switch as well, could this be part of the problem.

What steps would you recommend?
Flow switch fault will only stop it firing, water will still pass, only eventually go cold.
OK, maybe I'll look at filters, then blending valve then heat exchanger in that order, as I reckon HE would be most expensive to replace.

Thanks for your help Tibbot
Hard water area? do you have a Softener or scale reducer in the cold feed? if not suspect scaled plate heat exchanger! ;)
OK thanks Boilerman, I suppose there is no way of knowing (unless it's visually obvious) until you replace exchanger if its that or not. Correct in saying hard water area and there is no softner.

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