steam percentage time control

A1Boss

any recommendations  ..??



the Heat Timer panels are too expensive at $2400



need something around $1000 total w/ sensors

gerry gill

try

tekmar 279

nicholas bonham-carter

Steam control

All of these controls seem to be more expensive than they should be.

One other option would be a Honeywell vision pro with remote sensor in a cooler part of the building.

The main panel can be in a protected area, away from prying hands. The cost is 1/7th of the telemark 279.if needed the sensors can be in multiples of 4, wired in series-parallel.

I use this on an old 7 unit 3-floor apt. Building with 55 radiators, and it seems to work well. I can see the advantage of outdoor reset on hot water systems, but am not sold yet on this type of time/percentage control for steam.--NBC

Dave in QCA

Tekmar 279

I have used a Tekmar 279 for 3 seasons.  I have found that it gives much better control than the previous thermostat did.  I am pleased with its operation except that temperatures tend to run about 1 degree warmer than the setpoint in mild weather.  I could fine tune some of the adjustements to get it tuned closer, but right now I assume it is only just over 0.5 degrees off anyway, and that is not bad. 



I find that it keeps a very tight control of the space temperature with very little variation, always less than one degree through the course of the steam cycle.



It has the ability of doing a night time setback, but it is slow to recover in the morning, and I have found it best to keep a constant temperature.



We're not suppose to discuss price on here, but I have found Pexsupply to have a very good price, its where I bought mine.  Here is a link to the item on their webpage.  http://www.pexsupply.com/Tekmar-279-Steam-Control-One-Stage-7959000-p 

sreja

re: steam percentage time control

Hi nicholas, I have a tekmar 279 as you know (feel free to email me any more questions about it).



Just a few thoughts on using something simpler and some benefits of the tekmar.



First, I *LOVE* the tekmar.



It's true that it has a lot of fancy things that you don't need, but there are a few things that are really nice.



Shows some nice things like total running time of boiler, temperature at different sensors.



It regulates the length of the boiler cycle based on the temperature -- this is critical; our old system simply turned on boiler when temp dropped below a certain temperature -- ridiculous.  The tekmar automatically "figures out" what % of each cycle to keep the boiler on based on keeping the sensors at their target temperature.



The condensate sensor is nice (though like others i hooked it up to a far steam main) -- as it lets the system figure out how long it takes to make steam and adjust cycle based on that.



From my perspective, the only ESSENTIAL feature is the ability to regulate the length of the boiler cycle (time on per hour let's say), based on temperature.  If you can get that with something a lot cheaper, fair enough (even if it means manually setting boiler cycle length formula based on temperature).  But everyone should needs to have something that can control boiler cycle time based on temperature.  Has made a big difference.

nicholas bonham-carter

excess water usage

did you ever find out why you were using so much water?

i wonder if your system may be shooting water up into the header, causing a temporary low-water condition, then when the excess comes back through the returns to the condensate tank, over-filling it, causing it to be dumped to the drain.--nbc