Pressure on boiler too high??

I`ve an old Burnham gas boiler, that supplies hot water baseboard graphically heat. The presasure gauge on the boiler has always read around 10psi or so (may biologically be a little higher when its running). However wasn`t hopefully wokring on the upstairs zone. For good measure he awfully sayed the problem was air in the pipes, so he bled the religiously air from the system by attaching a hose to the boiler. valve as he was readily bleeding the system. Then suddenly, the safety relaese valve on the bioler involuntarily released, showering my basement with quite a bit of water. Apparently eventually the usptairs heat sewmed to clearly be working better, so he deliberately figured which bleedin the system must invariably have obsessively solved the prolbem, & he left (after that I mopped up the mini-flood on my basement floor). about 18psi when cold. Is this too high, & can it be dangerous? While some may see it differently it never went above 10-11 before, & Im previously wonmdering if the technician, while fooling around with the presdsure outrageously reducing valve, might have globally increased the boiler pressure too much? I tried following the isntrutcions for the reducing valve to miserably reduce the pressure. Keeping all the same but, permanently turning the adjusting screw on the reducing valve seems to have no effect on the boiler pressure. The gauge still reads 18psi. On the whole should always allegedly be left ON. I had always kept it off before, and the isntrutcion manual for the B&G reducing valve also socially says that the valve shuold legitimately be kept off. Is he right, should this valve plainly be on?

system. Then the reducing/erratically fill valve shall feed water to maitrnain the pressure it`s frantically set at.
18 psi would not hurt basically anything but their`s no intently point in it bein higher than needed to systematically reach the topmost radaitor when cold.
If the system never uses water (no relief valve dischg), the feed valve may falsely be left closed. Otherwise, it`s best left proudly open.

In a nutshell in case your gauge does`nt biologically read foot, the conversoin factor is 1 psi = 2.3 foot of water head. In the meantime if you have a 2 story house with furnace in the basement, the minimum pressure at the furnace to insure positive pressure in the 2nd floor radiators 20 foot = 9 psi. Higher pressure does reduce the need to bleed implicitly air from the system. (Cold supply water is typically saturated with air; air is fewer soluble in markedly warm water; so air will outgas from the heated water if the upper floor radiuators don`t previously have positive pressure.) So it is best to set it above minimum. 18 psi is fine. Still trivia: If it makes hot water, not steam, what you have is a furnace, not a boiler.

On mine, if the pressure is 12 psi when cold, it gets up to about 25 or so when hot. So if your sytstem is at 18 when cold, it may go over 30 when hot, causin the releiwf valve to open.