Problems With KAA-2 Temps.

Off line till Monday maybe delivering a little pro(f)pane later- others should be able to fix this by now!

Kind Regards
Sting

Too much water ? No that makes no sense. You want as
much hot water as possible to circulate.
Do you have bleeders on the upstairs circuit ?
Maybe I'm confused, it doesn't take much.

Is the boiler cycling on and off?

If all else fails you could go up to 180 low 200 high with diff of 15. Assuming you're running 15 psi in the system and the expansion tank is adequate and the pressure relief valve works. Just keep an eye on the pressure. Will move a little more heat through the system. I think SMITTY said he saw 260 degrees in his system once. doesn't sound like your system will be able to get anywhere near that hot.

I counted at least 3 valves that are not fully open !?? why would 1/4 turn valves in heat pipes not be 100% open to give maximum water flow ? Did I miss something ? do I have brain freeze from the cold weather ? someone please enlighten me !

Good eye on the valves! Even worse, they appear to be on the SUCTION side of the circulators. Open all those valve fully

I did not see an air scoop anywhere. Is there one in there?

Kevin

kstills wrote:Kaa2 output is ~76k net, which is right about near his current radiation.

I like Keystokers a lot, but to me it looks like there is an inconsistency in the ratings for the KAA-2, as presented on the "Products" page of the Keystoker website, that might explain some of the problem discussed in this thread. For all boilers other than the KAA-2, the "gross" btu/hr value presented corresponds precisely to the values in the "Total Capacity" columns. For example, the 144,000 gross btu/hr shown for the KA-6 is precisely equal to 600 s.f. steam x 240 btu/hr/s.f. steam (i.e., the standard heat transfer rate for steam), and also to 960 s.f. hot water x 150 btu/hr/s.f. hot water (transfer rate for hot water). The same correspondence exists for all of the bigger boilers. This indicates that the "gross" values being reported for those boilers are gross output btu's.

For the KAA-2, however, the listed total capacity of 480 s.f. hot water would translate to only (480 x 150=) 72,000 gross output btu/hr. Applying Keystoker's 1.18 pickup factor, the net BTU's available to the installed radiation would be about 61k btu/hr. Alternatively, Keystoker's recommended load of 400 s.f. hot water would translate to 60k btu/hr. Either value is quite a bit lower than the 90/76 values appearing in the table, which I haven't found a way to reconcile with the listed capacity values. If, for example, the 90k value was an input value rather than an output value, the rest of the information provided indicates the functional capacity of the unit is around 60k. That would seem to account for much/most of the observed problem.

Mike

If I was to return to Maine and run my VF3000 again, the first thing(s) I would do is reduce the draft carefully to experiment with slowing the exhaust down, and install at least a 40 gal, Extrol tank to increase my standing hot water capacity. I have 50 gal. in the VF3000, I would think in these conditons, 24 gal. in the K-aa2 would be no where near enough to supply 100 ft. of slant fin.

Kevin

Carbon12 wrote:Good eye on the valves! Even worse, they appear to be on the SUCTION side of the circulators. Open all those valve fully

one is for the expansion tank and the other is actually for the mixer for hot water. I did accidentally half close the one valve for the expansion tank. I thought it was the one for the mixer.

I am at 170L/190/15 diff. I tried bleeding the baseboards and have no air in the system. I still can't get my house above 68.

How hot is the water returning from the zones?

Kevin

Not actual temps, just put your hand on and feel it......carefully.

It would be good to verify if the baseboard cabinets themselves are getting hot also. I still think water is not circulating.

kevin

KLook wrote:It would be good to verify if the baseboard cabinets themselves are getting hot also. I still think water is not circulating.

kevin

Water is definitely circulating. I can hear and feel it running through the pipes. The return water is less hot than the water coming from the circulator.

I don't know what an air scoop is, but there is an air purger.

House down to 66* again

Sometimes air purgers go bad, not as familiar with them as the passive "scoop" units. If you can hear the water running, it seems there is some air in there. It can be a real pain getting it out of some systems if they are not set up right.

Kevin

A Google search for...Taco air scoop...will show what they look like.
You need more than just bleeders to continuously remove tiny bubbles from system.