Buderus R2109 Controler

Larry_10

hi I have a g115 28 with 2 zone 1 cerc for each zone I have a r2109 and taco sr502 switching relay on the 2109 it says I can have my cerc run 10 mins after a call for heat
but mine dose not.

I put the dip switch 1 and set it to on

now on the 2109 I have dhw priority and the tank cerc is connected directly to the r2109 so the sr502 dose not need to do priority.

the way the sr502 is set now the hydro air is on pump one and the baseboards are on pump2 there is a pump 3 on there
but it's not used should I take everything off pump one and use pump 2 and 3

the jumper is set no priority so there is a jumper on zc and p so pump 1 and 2 work together

but is this why my cerc dose not stay on for 10 min after a call for heat should both heat pumps be on 2 and 3

because it looks like pump one is made for dhw but I don't need the sr502 for that so should I just use pump 2 and 3 for heating will this fix my problem

thanks

Mark Avron

Hey Roosterboy,
It sounds like there is no connection between your 2109 and Sr503. Is that correct? Secondly, it doesn't matter which relays you use (1&2,2&3,etc.) as long as the priority is off. In order to utilize the purge feature as well as condensate protection and DHW priority, the controls should be wired as follows: Power to the Sr503 (H) should come from terminal 63 of the R2109. REMOVE JUMPER between terminals H & ZC on the SR503. Line power from service switch goes to ZC on SR503 (also wire to N). This wiring configuration will work as long you are not using a t-stat that requires constant power. Please contact Buderus customer service 800-BUDERUS for details.