Optimal temperature for a 1250 kW boiler?

[LauPro]

In a building sits a 1250 kW boiler for central heating. Its thermostat is set at about 80 degrees C atm. I'm trying to search a way to save costs with this one. On many sites i read that it is most effective to lower the temps (like 50 degrees C).

It is a gas boiler with simple modulation (off, low, high).

What is the best thing to do? There are about 150 radiators and 4 air units attached to it. 25 radiators and 2 air units are in use atm.

[slimwoodie]

lowest practical range with Gas is in the range of 150* F average water temperature

otherwise you end up with flue gas condensation ..

the boiler mfgr may have different limits, ... i.e. Steel, vs. Cast Iron

[LauPro]

lowest practical range with Gas is in the range of 150* F average water temperature

otherwise you end up with flue gas condensation ..

the boiler mfgr may have different limits, ... i.e. Steel, vs. Cast IronThe limit of the boiler is 120 degrees C. Your 150 degrees F will be about 65 degrees C, so that is the minimum?

I'm not changing anything atm, just informing the posibilities.

[slimwoodie]

what exactly do you have for a boiler ...?? :confused:

i have worked on/ certified to work on euro equipment like UniCal ...

[LauPro]

I can lookup the brand for you. But it on old one from 1993. Not very spectacular. It is very analog has a simple thermostat so it is posible to adjust it.

[DPinst]

On the market is a wide variety of reset controllers that vary the boiler temp in response to outdoor temp . Had a lot of sucess with Tekmar controllers , simple to install and operate with a wide range of options.