Pressure gauge question

Andy_14

Attached picture shows system and gauges.

Do these pressure gauge readings sound ok? I thought shut down should only be around 12psi?

System shut down. Both supply and return gauges read ~20psi

System running, supply reads ~22psi

System running, return reads ~27psi

Al Letellier_9

pressures

They seem OK to me. You will see higher pressures on the return gauge as you have two circulators adding head to the ssytem. If the pressure rises on the supply side, it can trip that safety valve, which should be piped down to the floor in case it does blow. Fine looking install otherwise.

Al Letellier_9

pressures

Looks OK>>>>you have two circs adding head in that side of the system. Nice looking install but pipe that safety to the floor. IF pressured builds on the supply side, it will blow and make a mess.

Andy_14

Thanks Al. My biggest concern was the ~20psi readings while the system is shut down.

That is an old picture that was already on my computer. The PRV has been piped to the floor and a condensate loop has been added.

Brad White

This is the high point of the system apparently

It need not be higher than the minimum operating pressure of the boiler (enough to satsify the pressure switch). As Al was suggesting, give yourself a margin between your operating pressure and the relief valve setting.

Your readings of 20 static and 22-27 dynamic is your primary side pressure drop: 5 PSIG or about 11.5 feet of head. You may be able to plot your actual flow on the pump curve.