Tekmar 356 question

GM_73

Tekmar 356 is showing the mix demand icon in lower right screen. It however doesn't show any pump percentage in the bar graph. Is this normal?

hot_rod

Scroll through all the parameters, with the item button I believe, what is the supply temperature. Is the system heating? Supply to the system warm?

GM_73

Customer is stating floors aren't as hot as they used to be. We replaced the Tekmar about 3 weeks ago because the screen was blank and the inject ion pump wasn't working. Customer sent screen shot of display, will be going there Monday.

Mix temp- 113

Boiler supply 183

Outdoor ambient 52 (Chicago in January)!

Thank you

109A_5

I believe just because there is mixing demand that does not guarantee injection pump activity if the Mix Target has been satisfied. There may be more influences than just Mixing Demand for injection pump activity. Some settings may have to be changed for their comfort at the expense of best efficiency. Maybe it is just the weather, not enough heat loss since it is unusually warm out.

GM_73

Thank you for the responses thus far, really appreciated! Went to customer today, Jan. 13. Still not heating enough. Since installing the control, have yet to ever see the pump running. Test button does actuate pump. Jumpered the injection pump and manifolds warm nicely, supply and return which tells me IF the injection pump runs, they will have heat. I have set this up as a reset control. Couple of points I'd like to note.

1-Set outdoor Design to 0 degrees- Chicago. Room temp to 75

2- Looking at the manual one would believe that jumpering terminals 7 and 9 would actuate pump. However I now realize that other criteria must be met for that to happen (supply temp and boiler return temp).

3-As a test I'm considering changing terminal unit setting to fin tube or cast iron radiator, see if the inject ion pump runs (briefly).

4-Supply sensor reads 113 degrees tho a thermometer reads supply as 89-90. Possible incorrect placement of sensor? System has worked perfect ly past 22 years however…

Sorry for the rambling, frustrated.

109A_5

Your Item " 4-Supply sensor reads 113 degrees " This does not agree with previously posted information.

If there is demand and the boiler is running what is controlling the boiler's circulator ? If the boiler is running and the boiler's circulator is running, 113 degrees (Supply sensor) seems low and 89-90 would be even worse.

What is the Target Mixed supply set for ?

Maybe the sensor is bad.

Another thread (link below), long read, but may help you.

Claimed it worked for 21 years, and then something changed, it was resolved (long story short), the boiler pump was not wired into the system correctly. In this case when the Tekmar 356 sensed the boiler was hot enough it would end the call to the boiler and that would turn off the boiler's circulator. So no more heat to the system until the Boiler Supply sensor cooled enough. Tekmar's note below warns about that situation. In that case the system's drawings helped a lot.

https://forum.heatinghelp.com/discussion/comment/1869060

Is this set correctly ?

109A_5

Looks like the Boiler Supply / Boiler Return, Mixing and the Outdoor Reset Sensors have the same resistance properties.