Mixing valve on outdoor reset

nick

I am an HO with Weil Gold boiler running three zones of iron radiators, indirect water heater and a hydrocoil that heats half the house. On cool days/nights when I need just a little heat, the radiators get very hot and overshoot the thermostat by as much as four degrees - uncomfortable. it seems to me I need the boiler to always crank high temperature in order to run the hot water and hydrocoil. would it be possible to attached mixing valves w/ outdoor reset to the iron radiator loops to alleviate this problem? is this the best way? if so, would I need one valve for each zone? what brands would do this? thanks

Unknown

tekmar

for one company.

I would use an injection control that injected boiler water into a loop serving only the iron radiators. The control would partially reset the boiler loop to the baseboard or air handler zones, which also saves money. It has a water heater input that delivers full temp boiler water when the water heater calls. It widens the differential of the boiler water temp during mild weather to prevent short cycling. It protects against low return temps that are harmful to the boiler by slowing the injection pump. All around, it is what you are looking for. Have a tekmar rep help you select the correct one for you.

Noel

Gregg Jackson

4 way valve

Nick,

Another possibilty is to come off of your boiler with a pump for the DHW, a pump for the hydro-coil and then break down to a lower temp with a 4 way valve. This could be accomplished using a Viessman HK-1 kit. This control mounts right on the 4 way valve and modulates the 4 way based on outdoor temp. It also has boiler enable capability and DHW priority. It would also give you boiler protection. If zoning was an issue you could simply add thermostatic radiator valves at each rad. This would give you ultimate comfort and control. Just another idea.

Gregg