System 2000 HX question

GW

Hello,

we have a lady with a system 2000. She's getting heat migration when the DHW comes on. My guess is it's a clogged HX. Does anyone have any thoughts? My tech was surprised to see that the zone valves need to hold back against dead heading, only leaving a tiny 1/2" line to the HX. Anyways, thanks for any comments.

Gary Wilson

Robert O'Connor_3

System 2000 HX question

The circulator never dead heads. The HX is a bypass from supply to return so water is always moving. Things to determine: 1) Is there a problem with hot water recovery? 2) If there is more than one heating zone do all zones overheat? 3) Does the burner short cycle on the high limit aquastat while only making hot water?

A yes answer to #1 or 2 indicates that the boiler side of the HX has some blockage. If the HX is clean then the problem is more likely a zone valve problem, cracked ball, dirty seat, etc.

GW

reply

hot water recovery is fine, no problem there. two of the four zones hold back the flow, two don't. I'm not familiar with z-v weeping by like this, is it a zv prob you think?

gary