Johnson A419 (or similar other) question

[maple1]

After experimenting with an ordinary EHWH thermostat to control my sidearm circuit/electric tank temp, I'm thinking about replacing with one of these. What I have works, but it short cycles more than I like. Plus I like the thought of another digital display.

Question is, do they make one of these controllers (or similar of another brand) with two temp sensor inputs? If I could get one with two inputs, and two control circuits, and have one make on rise while the other breaks on rise, I could clean up some of my other control stuff at the same time with one unit. I guess it would be like 2 aquastats in one unit.

Thought I'd better check before I order something that I could have gone one better with...

 

[rkusek]

I could be wrong but I don't think the A419 will do the differential job that you are looking for. The A419's differential setting is a fixed input that you enter on the keypad. I have a A419 to control my air handler when the boiler water is warm enough to put out heat. For DHW heating off storage you need something that compares to temp of the boiler water and temp of the DHW to decide whether or not to charge the tank. http://www.mydtcstore.com/ordering--contact.html Here is a site someone on hearth referenced awhile back that I was going to look at when I connect a sidearm to may DHW.

 

[rkusek]

http://www.mydtcstore.com/wood-boiler-outdoor-reset-control--temp-control.html
Here is a specific item I found on that site that seems to be pretty useful for $89. It has 6 temp probe inputs and 3 output relays that can be configured many ways. Watch his video on this item. Outdoor reset, boiler control, differential control of a water heater, freeze protection, anti-cycling, and basic logging all seem to be covered.

 

[BoilerMan]

Wow! I'm getting myself one of those! That is THREE aquastats in one with many more features.

TS

 

[maple1]

That's a neat looking gadget - I think I'd have my hands full figuring it out though.

After some more looking, I think either a Johnson 419 or Ranco 112000 would do me. I've got a thermal switch that will shut down my sidearm circuit when my storage gets too cool - I'll use the Johnson/Ranco for the temperature control part. Played with my setup some more tonight. The ultra simple & cheap EHWH stat is more erratic than I'd like & has like no differential to it. Getting one might be another story - living on this side of the border has it's issues when it comes to that sometimes. Have one more local supplier to try - then I might be stuck with Ebay. Unless someone on here has one they'd part with?

'BoilerMan'? You look a bit like this other guy that used to hang around here - even have the same garage by the looks of it...

 

[BoilerMan]

Haha Maple it's me, I just thought it's be best if I not use my full real name as the screen name, don't know if it makes any difference or not. BTW that is my garage ant 1983 and 2003 VWs in the same metallic paint... 20 years of German quality!

TS