Help with high/low limit boiler relay switch / aquastat
#1
11-10-10, 04:40 PM
Help with high/low limit boiler relay switch / aquastat
I have a wood boiler I am trying to add into my radiant heat loop. I have all the connections for the water set. I need help with the electronics. Here is the goal:
Circulator always runs and the heat exchanger for the water heater is in the main loop.
Thermostat NOT calling for heat:
high limit set to 165
low limit set to 125
blower should run when the water temp is below 125 and turn off when water reaches 125 (there is a differential so the numbers will be a little further apart)
Thermostat calling for heat:
high limit set to 165
low limit set to 125
blower should run until the water temp reaches 165, i believe there is a 10 degree "built-in" differential
So that is it, the main loop should never drop below 125 and the water should never get above 165.
I already have a few zones with a control box that turn on a circulator which pulls from the main loop, when one of these calls for heat the box sends the signal to the boiler to call for heat.
The aquastat on the boiler seems to be nothing more than a high dial, low dial (with differential), each side has a relay with common, normally open, and normally closed.
I have no idea what brand it is or how to find any more info. Does anyone know how i need to wire this thing to get what i want?
Eventually I'd like to get my gas boiler wired back in as a backup.
I'll try to get a few pictures soon, pictures always help, right?
Circulator always runs and the heat exchanger for the water heater is in the main loop.
Thermostat NOT calling for heat:
high limit set to 165
low limit set to 125
blower should run when the water temp is below 125 and turn off when water reaches 125 (there is a differential so the numbers will be a little further apart)
Thermostat calling for heat:
high limit set to 165
low limit set to 125
blower should run until the water temp reaches 165, i believe there is a 10 degree "built-in" differential
So that is it, the main loop should never drop below 125 and the water should never get above 165.
I already have a few zones with a control box that turn on a circulator which pulls from the main loop, when one of these calls for heat the box sends the signal to the boiler to call for heat.
The aquastat on the boiler seems to be nothing more than a high dial, low dial (with differential), each side has a relay with common, normally open, and normally closed.
I have no idea what brand it is or how to find any more info. Does anyone know how i need to wire this thing to get what i want?
Eventually I'd like to get my gas boiler wired back in as a backup.
I'll try to get a few pictures soon, pictures always help, right?
#2
11-10-10, 05:08 PM
Yes, of course, pictures always help... we'll wait to see those before commenting...
Specifics about the equipment are also worthwhile... what make/model boilers are you working with?
When you say 'radiant heat', do you mean tubing in the floor? or what ? exactly what type of heat emitters are you using?
Does your existing system use individual circulators for each zone, or are there electric zone valves?
Specifics about the equipment are also worthwhile... what make/model boilers are you working with?
When you say 'radiant heat', do you mean tubing in the floor? or what ? exactly what type of heat emitters are you using?
Does your existing system use individual circulators for each zone, or are there electric zone valves?
#4
11-10-10, 05:18 PM
here are some pictures
Picasa Web Albums - Eugene - Untitled Album
The group of three screws on each side are simply relays like this:
This is pretty much the setup:
Picasa Web Albums - Eugene
Also a picture is in the album with the wood boiler in the loop, it sits right before the gas boiler.
The wood boiler is a Royall 6526.
The gas is a weil mc-lain CGI-5
the water heater is first in line
Then the staple up pex (1500ft 5 300ft loops), mixing valve set at 150
Then the basement concrete and garage concrete (4 - 300 ft loops in basement, 2 300 ft loops in garage), mixing valve set at 100
Currently one thermostat controls the basement and another controls the first floor staple up zone.
Each thermostat and circulator pump is wired to a zone on a SR504-EXP-1, taco switching relay
there is a circulator constantly running on the main loop
when one of the thermostats calls for heat, the switching relay turns on the boiler. (currently a gas boiler)
I understand that my water heater will constantly be fluctuating with the temp of the main line.
Eventually I will want the Gas boiler wired in again and set to a lower temp, so if i leave for the weekend and the fire goes out, the water will stay at least 90 degrees
I think it is fine though, i fell like it is a huge waste to keep the main line at 165 always.
The group of three screws on each side are simply relays like this:
This is pretty much the setup:
Picasa Web Albums - Eugene
Also a picture is in the album with the wood boiler in the loop, it sits right before the gas boiler.
The wood boiler is a Royall 6526.
The gas is a weil mc-lain CGI-5
the water heater is first in line
Then the staple up pex (1500ft 5 300ft loops), mixing valve set at 150
Then the basement concrete and garage concrete (4 - 300 ft loops in basement, 2 300 ft loops in garage), mixing valve set at 100
Currently one thermostat controls the basement and another controls the first floor staple up zone.
Each thermostat and circulator pump is wired to a zone on a SR504-EXP-1, taco switching relay
there is a circulator constantly running on the main loop
when one of the thermostats calls for heat, the switching relay turns on the boiler. (currently a gas boiler)
I understand that my water heater will constantly be fluctuating with the temp of the main line.
Eventually I will want the Gas boiler wired in again and set to a lower temp, so if i leave for the weekend and the fire goes out, the water will stay at least 90 degrees
I think it is fine though, i fell like it is a huge waste to keep the main line at 165 always.
Last edited by NJT; 11-10-10 at 09:01 PM.
#5
11-10-10, 07:02 PM
possible solution?
This is the only way I can think of making this work.
Picasa Web Albums - Eugene
I'd need to add a relay and a24v power source. Maybe I can just put the relay in the 24v loop between the gas boiler and the taco switching relay box?
Picasa Web Albums - Eugene
I'd need to add a relay and a24v power source. Maybe I can just put the relay in the 24v loop between the gas boiler and the taco switching relay box?
