aquastat location

patrestaino

have a modine hydronic hanging in my garage
run by it’s own zone and thermostat .. the aquastat ONLY turns on the fan to the unit to blow air over the unit. it’s a strap on
  1.     should the stat be on the supply or return ( it’s on the return now)very close to unit
2.it’s a honeywell l6006c with high set at factory 200 ..what should i set low at and set the temperature differential at ?

EBEBRATT-Ed

Yes I would put it on the return. You only need 2 wire power into R and W to the fan motor. The control makes contact on a temp rise to start the fan.

I would set the dial to 115ish with a 5 degree diff. You can adjust it if you don't like those settings. It's purpose is to start the fan when the pipe gets hot.

I assume your not starting the boiler with it

patrestaino

no boiler is started by a thermostat that controls a zone valve on the boiler and starts the water flowing ..Aquastat controls FAN ONLY on hanging heater … what i understand the 115 turns the fan on But what does the 5 degree heat differential do ?

pecmsg

Start at X
stop 5* lower. 

patrestaino

k

EBEBRATT-Ed

@patrestaino

If hooked up as I posted above the fan should start when the pipe reaches the temp on the aqaustat dial setting (front cover) approx 115 degrees.

So if the fan starts at 115 it will shut off at 115-5 (if you set the differential at 5)

So with those settings the fan would start at 115 and shut off if the water drops below 110


After you try it yo may have to play with the settings.

For instance, when the water gets down to 110 if the air feels too cold then raise the on setting from 115-120. Then you will be at 120 on and 115 off

If the fan cycles on and off to much (it should stay on if you have enough heat delivered to the heater) depending on the units capacity Then raise the dial setting on the front and widen the differential until you get back to the off setting you want.

Your setting on the front is the cut in setting----fan starts
Your differential setting (inside control) determines the cut off ----fan shuts off

Cut in minus differential=cut off

bburd

The only purpose of that aquastat is to start the fan when the coil heats up and can supply warm air, and stop the fan to avoid a cold draft when the hot water flow stops.