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Watercooling a PC with a central heating radiator? Answered

So I'm completely new to water cooling, I own a closed loop cooler and I know the names of the water cooling parts and assembly, but I have no real experience.

I presume it's possible to use a normal radiator as a passive radiator in a loop, but I've got a couple of questions. First, do I have to be worried about what the radiator and waterblocks are made of, are the metals important? Second, will I need a significantly more powerful pump than the standard D5?


P.S. the rad I had in mind is this http://www.screwfix.com/p/flomasta-type-11-single-panel-single-convector-radiator-white-300-x-800mm/38602   It's rated for 1505 BTU/hour, which equates to 441W, which is in theory plenty my PC (4670K, HD7850 which I'll probably upgrade in the near future)

The reason for using this kind of radiator is because they're far cheaper and passive, although I suppose the increase in pump power may negate quietness of no fans. It's also more fun ;)



4 years ago

i don't think the heat transfer to the air would be good enough from a flat radiator. you need somethig like a car radiator with fins on it to increase the surface area.


4 years ago

I'd recommend sticking with components designed for this application.

Even fans rated at 22-Db is considered silent; some go as low as 10-Db. these will provide you some awesome cooling, and produce next to no sound. Perhaps buy some rubber mounting screws too ?


Sure the rad you listed is rated for 441W, IF the water temp is 70*C (Aprox 170*F) I imagine that your coolant temp would be something significantly less. (Personally I don't like to see temps higher then 30*C ( maybe 35 on a high intensity game)

PS: YES the materials are Important !

Unfortunately, if you want to mix standards from 2 industries, there will not be %100 certainty.Because most Rad's use copper pipes (like most water blocks) I'll give you an %80 certainty that it could work. whats a few extra $$ VS your cooling system?


4 years ago

Copper for a CPU block is usually better because it can conduct more heat but with water cooling that is not as big a factor because the water moves far more heat than air so just having the water flow taking away the heat much faster the more important thing is the design of the block and its ability to get good water flow through it. So a well made block that will not leak (has good seams and such) and has good contact on the CPU face can be of either copper or AL or a combination of both. Consumer feedback and reviews might help you in the right direction.

The factor that will influence your pump flow the most is the length and diameter of the tubing. Pushing water through a long tube run takes more power. The volume of the water flow will be determined by the power of the pump and the resistance to the flow. It works much like electricity. Volts and amps. A smaller and longer tube will cause more friction and the pump pressure and water pressure will go up because moving the water through it will be harder. But you can get the same amount of water volume through it by making the water move faster through the tube.

I think the true critical factor is the water volume flow through the CPU block. Its kind of like the light bulb in an electrical circuit. That is where the greatest resistance to the water flow should be. If the pump can move enough water through the block then it should work OK. A larger radiator is like having a super big tube. The water will move through it slowly and it will be easy to push so a larger radiator should not cause a problem. I would lay it flat rather than stand it up. The air will move by convection up through it that way.


Answer 4 years ago

Second your point on hose sizes, and the Cpu being the bottle neck !

The larger Rad will only add some length to your system, The pump shouldn't have a problem