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[caper]

hello all,just installed a few mixing valves for the system,main floor is cast iron rads and basement is infloor ,what should the temp be for each ...thanks for the help...

[slimjim]

Cast Iron rads can be run with straight hot water, just be cautious of cold water returns when the zone first starts returning to the boiler, you should try not to exceed more than a 20 degree differential on the supply and return temps at the boiler.
  In floor radiant, pay attention to the manufacturers suggested temps, Ultra fin for example used in wooden floor joist bays can be used straight off the boiler whereas staple up and in slab will need to be reduced to below 130 degrees, this is where temp gauges when installing the system are a good investment!

[caper]

ok thanks, I turned down the mixn valve for the  cast rads to 150, and their still very hot,may try 140 or would that be too low,my basement which has the in floor in concrete is being troublesome since I turned everything on yesterday,the supply lines appear to be hot,but nothing on the return line yet and its been 12 hrs,return line isn't even warm yet.....this all worked perfect last 2 yrs,but I got the mixn valves just put in........what could be the issue there,why isn't the water returning back,there is approx. 8 runs so there cant be a kink in them all...could it be that the water isn't hot enough,maybe adjust mix valve........a lot of info,what do u think guys...

[slimjim]

Check to see that the mixing valve is in properly, I have installed them backwards myself before, also did you purge each individual loop on the slab loop separately, you probably have air trapped somewhere, it could even be at the circ itself.

[caper]

ok thanks ,just tried the infloor in the garage floor,mmmm not working either,buddy must of screwed up somewhere,both zones where the mixn valves were installed and both are in floor don't work,mmmhowever my main floor where the cast rads and a mixn valve was installed works perfect,instant hot water,sound like he messed up with something to do with the infloor and valves,he'll be here after lunch,ill let you know what the issue was,hope its a small one....

[slimjim]

I would bet that when the mixing valves were cut in you got some air in the system and now it is lodged in your circulator!

[caper]

hello guys, little issue ,nothing serious,as mentioned before,the last two years i had no mixn valves running in my home,main floor is cast and basement and garage is in floor radiant, hers my issue, and i know im beating a dead horse here,main floor rads working great as usual,hot as soon as theromstate calls for heat,last nite i checked basement at around 130am,temp was 71 and calling for heat,at 6am when i got up,still calling for heat and temp was still 71,this never happened the last two years until now when i got the mixn valves hooked up,i am getting really pissed as this was supposed to be a good thing,lowering temp in basement floor,(save alittle wood,easier on furnace etc...) but its becoming a pain,ive played with the valves,checking and re setting, at the top of each loop shows approx 130 degrees,12 inches lower just before it enters the concrete shows 120 or less, another question, why the heck is it taking so long for the return to come back, maybe i just shouldve left everything alone......pumps are all good, i just wish now i didnt install any mixn valves.....any suggestions beside turning up the heat in the valves... thanks guys,once again, sorry for bringing this up again,but im getting really pissed with things not working the way their supposed too...again thanks

[LittleJohn]

For in-slab application, the lower the water temperature the longer the calls for heat will be.  Also you will see less heat striping across the room and should have a more even temperature thru out

It can take a while for the slab to heat up because there is alot of mass that the system is trying to warm up.

When you installed your mixing valves, where were the pumps located? because you need to have a pump between the mixing device and the radiant manifold/application, otherwise as the valve tempers the water it will shut down the flow to your radiant application and may eventually turn it off.