this was discussed, I think Neil or Paul stated 4 amps max?, but hey do have a relay output option to control higher loads like furnance blowers.
Do a search on this forum...
From Paul in another thread.Booster fans with Coal-Trol
"The key requirement for operation of multiple blowers from the variable speed convection output are:
1) Multiple motors must be of identical types. This means the nameplate model number and the fan attached must be identical. DO NOT mix motor types or sizes.
2) The total continuous current drawn from the Convection output must be less than 4.5A. (We rate the output conservatively at 2A, assuming that the other outputs are at their rated output.)
3) The total of all loads on the Coal-trol Digital must be less than 10A, otherwise the fuse blows.
Operation outside these boundaries may cause damage to the control module.
DISCLAIMER: We try to assist in providing special solutions to adapt to your particular situation. However, we cannot be responsible for damage to equipment caused by unreasonable application not within the ratings and/or published specifications."