how do you add a taco sr501 to a taco sr506exp

pennron

my situation is such. I have a very cold bathroom basically because of 15' vaulted ceiling. I installed 8' of baseboard and have a kick space heater under the vanity. I put this room on a separate zone with its own thermostat. I am using a burnham revolution boiler with a taco sr506exp control with 3 circulators (taco 007's) and a 4th for indirect DHW on priority. My "goal" is to get that bathroom zone's water temp as hot as possible to heat up the bathroom quickly. the taco 506 (with a pc702 outdoor sensor) does its job of keeping the water temps based on the outside weather temp that is the issue at hand.

I purchased a single zone taco sr501-4 control. My plan is to take the bathroom zone wiring out of the 506 and wire it into the 501. I'll power the 501 separately and also connect the thermostat wires into the 501. Now the 501will be it's own separate control for that bathroom zone.

My concern is if the 506 circulators are running using the outdoor reset control or the 506 DHW zone turns on while the 501 circulator is running how does the boiler know what to do? the 501 is turning on the boiler I assume trying to make 180 degree water flow through the bathroom radiators (my goal) but the 506 is trying to keep the boiler water at a temp dependent on the outdoor temp. Will this work?
regards...

STEVEusaPA

If I understand correctly, what should happen is whenever the 506 calls, it will target the boiler temperature based on the reset curve, or if set up for Indirect Priority, will target that temperature. When the 501 calls, it will do whatever, even run up to high limit on mild days.
When both are calling the 506 will take priority.
Without knowing the near boiler piping or your aquastat, that's just a guess. There are better ways to do this.
A Tekmar boiler control that targets 2 temps, + domestic + odr would be a better choice.

I also figure your kick space heater is sucking all the heat out of that zone and your baseboard is less effective.

pennron

steve thx for the input. I live in easton, pa so you get to know my climate. BTW, the 506 is setup for priority. If both are calling and the 506 takes priority over the 501 then that's NOT what I want. We need that master bathroom to heat up as quickly as possible for showering. If the 506 will take priority then that wont happen. The circs on the other zones are almost always running on the 506.

The goal is to have the 501 zone get to high temp water all the time and the 506 to use the outdoor reset like it does now with priority DHW (the way its set now).

Can you give me some more input on that tekmar control?
regards

mattmia2

Another option would be to add/replace emitters with emitters that can give you the output you need at the ODR water temp like panel radiators.

jpulls11

I did some quick googling. Looks like taco makes a priority circulator. I wonder if it could work with your exp switching relay.

https://www.tacocomfort.com/documents/FileLibrary/102-070A.pdf

pennron

jpulls11 said:

I did some quick googling. Looks like taco makes a priority circulator. I wonder if it could work with your exp switching relay.

https://www.tacocomfort.com/documents/FileLibrary/102-070A.pdf

hey I just checked that out. Looks very interesting. I'm surprised no one (taco) even mentioned this. BTW, Taco is basically useless. The only way to get things like this accomplished is to get a person who has experience with hydronic controls (easier said than done.) There are "probably" many ways to hook this up. I'm not versed in hydronics. This is OTJ training for me. It's becoming so frustrating I'm thinking of just having an electrician install a qmark in the wall heater with remote control and be done with it.
regards...

SteveSan

@pennron assuming you have sr506-exp-4 and standard sr501-4 take the N-H from the priority n/c zone 6 to the N-H on the sr501-4. Please give us a call at 401-942-8000 if you have any questions. We are here Mon-Fri 8am-5pm EST.

Joe Mattiello

Hi Pennron
im thinking you can parallel the end switch to boiler TT from both SR control. That should circumvent the boiler reset control which modulates the boiler based on reset.
if you energize the boiler TT terminals should fire to high limit.
I’m a little rusty so contacting Taco Tech support at 401-261-4890 will be best.
hopefully this was helpful  

pennron

hi:
Joe no offense but taco tech support has been poor to say the least. It might be covid related but I seem to get techs that ask me more than I ask them for answers. That being said here is a pic of my sr506 using a taco pc702 (2 stage) with burnham revolution boiler. DHW is priority. The taco sr501 is a standard sr501.

The 702 is set up somehow as 2 stage having to do with the revolution's internal circulator and injection system (beyond my pay code). That setup 702, 506 and ODR has worked like a charm for 15 years. I just need to take zone 3 out of the 506 and get it to work in the 501 (solo) without ODR but not affect the 506 when zone 3 (in the 501) calls for heat and the 506 circs are running with ODR.
regards...

pennron

I'm a homeowner with very little knowledge of these controls but from a logical standpoint all that needs to be done is take the zone 3 wires (blk/wh) and put them where the zone 6 wires are. Or taco should have a control with 2 priority zones. I doubt having both the DWH and zone 3 attached to zone 6 would work without possible damaging something?
regards,,,

pennron

I emailed TACO SUPPORT on this issue on 9/26/21. I immediately got a canned response that they would respond with an answer in 2 to 3 business days. Today 10/4/21 is the 6th business day...NO RESPONSE...

As I said Taco support is totally useless.
regards,,,

Joe Mattiello

Hi Pennron
I attached Taco Zone control wiring guide. It's a great resource. Call me at 401-261-4890, and I'll try to help you out with it. If it's beyound my skill set on control, I'll ask Master Dave Sweet to help:)

Dave H_2

The priority zone in the controller means to disregard all of the other heating zones and the outdoor reset. This is typically used for domestic hot water generation.

The work around for you is not adding a SR501 but rather a SR502 and some extra wiring. The SR502 will have the DHW circ and the bath circ connected to it. The endswitch from the 502 is going to the 506 priority zone with out a circ "underneath" it. You need to move the Zone 6 circ (DHW) and the Bath Circ from the SR506 to the SR 502