Re: Qs re hot-water-system (sudden increase in) PSI&temp.

Subject:

Comments:
: HKestenholz replied: : : With all the excellent clues you have given,... : Thanks, I tried :-). : : ...it is possible that you have : : localized heating of water to steam inside : : the boiler due to your failing circulator. : It's good to hear that the circulator may be : behind this issue. : : This would cause a rapid temperature and : : pressure jump, luckily not enough to dump : : the water from the system. : A quibble: our jump was sudden (from one : day to the next) -- I can't speak to whether : or not it was rapid. Having jumped (as : described in my original posting), both the : temp. and the PSI have stayed within the : new range. : : The pressure should not exceed 25 psig on : : a 30 psig relief valve as this is the : : resetting pressure once the valve has popped. : 10-4. The valve has not "popped" to date, : and, as I implied, the actual PSI is 3-5 PSI : below what the gauge tends to register : (before one taps on the glass :-)), so I : don't think we've actually gone above : 30PSI at any point (although we're coming : pretty close!). : : If the system pressure rises above 25 psig : : consistently after your circulator is repaired : : or replaced, get a larger expansion tank... : The gas-company people have noted that we : should have a larger Extrol tank -- however, : actually mounting a larger tank might : be tricky due to the positioning of the : pipes. : : ...or put another one on a manifold with : : the old one. There are pictures how to : : do this in the free lessons : : at http://www.hydronic.net : Is there any way we uneducated homeowners : can calculate our system volume? I'll use : Table 5 in : http://www.hydronic.net/hydronic/des/start.htm : to determine whether we currently have : an ET9 -- thanks! : : Severely black water can be corrected by : : flushing the system with clean water, : : not chemicals. : Are you suggesting that the blackened water : dripping from the circulator represents : the water in the system? The comments of the : gas-company people imply that the blackness : comes from the used [machine] oil (whose : color when new, as you know, is light brown) : and is nothing to worry about. : Thanks for replying, and advance thanks : for your (or anyone else's) further : thoughts!