Help with Heating Controls
I’m having problems with my DHW. I am unable to maintain a hot shower for any length of time. On a call for heat from the tap, the boiler comes on. But, the circulator cuts on also. Having the unintended consequence of heating the whole house. I know the problem has something to do with…
I’m having problems with my DHW. I am unable to maintain a hot shower for any length of time. On a call for heat from the tap, the boiler comes on. But, the circulator cuts on also. Having the unintended consequence of heating the whole house. I know the problem has something to do with the temperature controls on the aquastat(s). What should they be?
I have a Peerless Oil Fired boiler with a tankless coil. I have 2 aquastats. One, the L8124A triple aquastat is installed on the rear of the boiler. The other is a L4006A which is installed on the front of the boiler.
The current settings for the L8124 are High-200, Low-180, Differential-10. This seems to work as intended. The L4006a where I’m confused. Its currently set at 140 with the differential set to 5. When the boiler temp falls below 140 the burner kicks on as intended. But the circulator comes on also, making it harder to generate DHW . I thought DHW was supposed to have priority.
You ARE close.
The best thing for you to do right now is to call Peerless and tell them what your intentions (control strategy) are. They have pre-made wiring diagrams for nearly every application. Have them send you one.
Master Plvmber, thank you so much for that explanation. I’ve been trying to figure this out for a while now. RW, RB, make, break, differentials gets the head spinning.
Why would the L4006A be installed this way? Was it a mistake, or does it serve some sort of pratical function. ie reverse acting aquastat.
More importantly how do i rewire it.
Right now, the R7184 has the T-T terminals jumped. R7184 feeds(black and white wire) directly into L8124A. The Black is connected to B1, the white connected to B2. It does not go into a junction box first.
The L4006A feeds(white and red wire) into a junction box(with emerency shutoff switch), where the pair is joined with the house thermostat(also white and red) and then continues into the L8124A, where it connects into the T T connections.
Where do i make corrections? Should the wire running from the R7184 go into the junction box first in order to make a connection with the burner circuit?
Please help… I feel like i’m so close.
Those controls don’t offer “priority” settings. The problem lies in the communication between the L4006a and the triple aquastat.
The L4006a need only make and break the burner circuit. It need not emulate a call for heat and fully energize the triple aquastat, which is what it’s doing.
Rewire it in parallel to the burner circuit eliminating the T-T connections on the L8124A.