Strange, I usually use : push SCB, wait T=80-90%, push heat sink, wait T=15-20%, push another SCB.Finally, I would highly suggest replacing two of your HRP's with SCB's to be able to double bank keep your shields from going down. If you're unsure of how to double bank without cooking, hit your heat sink and as soon as your temp drops to roughly 20-15% hit your bank button twice. You'll slightly overheat for a second but it will quickly cool back down without melting your modules.
P.S. And it turns out that it’s more profitable to carry SCB class B since 3 charges of heat are just 6 scb,