outdoor reset with CI boiler

Ron Schroeder_3

Any time we reduce the temperature of the water going to the emitter, while maintaining the client's acceptable level of comfort, we save energy. Resetting the supply temperature with mixing valves and reduces the emitter temperature and extends the time interval between firing cycles. Reducing firing cycles reduces energy consumed.

The design temperature is only required for a few weeks per year. The other fifty weeks or so we save money when we reduce the supply temperature. This is where system efficiency rises despite whatever our appliance efficiency might be.

I would consider constant flow through the air handler and adjust the supply temperature of the water by means of a mixing valve. Cold slugs will be avoided and customer comfort levels rise.

Your esteem in the customer' eyes rises proportionally. (You don;t have to tell them that you got the idea here.)

SWS2_3

Is there a substancial efficiency benefit (worth the $) to install an outdoor reset controller with a non-condensing cast iron (oil)boiler? I am running 2 zones of hydro air and an indirect. All need 160-180 degrees. Thinking about a zone of radiant and are considering multiple control options.

Also is condensing a concern when one of the hydro-zones release a slug of cold water in an already hot boiler?? Thanks.