I'm not sure if this is the correct place so forgive me. My plumber is unable to come tonight and I start a new job tomorrow. My question is, can I just run the hot tap and mix with cold or will I blow my boiler up? (Can't get hold of plumber otherwise i'd ask him, obvs....) Prob too hot for a shower but was thinking I could run a bath and just add cold but don't want to overheat the boiler. Otherwise, it's a splash wash for me but my hair is filthy.... :( MTIA