Looking For A Honeywell

JTel

Hi, I have a Honeywell AQ475A running my heating system since October. Everything seemed to be working fine until now. The heating curve feature seems to not be working, no matter what the outdoor temp. is the boiler heats to the max. temp. (180 degrees). Last week the outdoor temp. went down to single digits and I expected the boiler to run a little hotter. But tonight the outdoor temp. is ammost 40 degrees and the boiler is maxing out at 180. I know the boiler maxes out when there is a DHW call, but in my case even when the space heating calls, the boiler goes to 180.

2 weeks ago I re-wired the controll to allow for more space heating zones. I used a TACO 3 zone switching relay w/ priority. Instead of using C1 & C2 on the AQ475 I wired my space heating pump into the TACO relay, the end switch from the TACO goes to TT on the AQ475. Seems to be correct I followed the instructions. I don't know if this is causing my problem, or possibly a bad sensor? Any help would be appreciated, Thanks.

kevin

what are the

trouble shooting protocols? I am not familiar w/ the honeywell od reset. check your sensor for the proper ohmage at the given temps.

[Deleted User]

Did the

addition of the new relay coincide w/ the AQ problem? If so, reconnect the control as before & see if it works.

We have used the AQ on several jobs w/ constant circulation & boiler temperature reset. Aces so far.

Glenn Harrison

Try going here,

Honeywell Technical Literature

and enter AQ475. This will provide you with any literature that you may not have to diagnose this further. If this does not, send an e-mail to- Bill.Wolfe@Honeywell.com -if Bill doesn't see this first. Bill is our Honeywell rep on the wall and would be more than happy to help you further.

Sorry I can't be of more help as I am not personally familiar with this control.

Glenn Harrison, Residential Service Tech

Althoff Industries Inc. Mechanical and Electrical Services

Crystal Lake, Illinois

Althoff Industries website

BillW@honeywell

AQ475

To check the sensor output, you need a meter. At 77 degrees the sensor should show 10 kilohm. If it does not, the sensor is defective, replace it with part # 32002100-001. The OA & water temp sensors are the same. Go to the following website: http://hbctechlit.honeywell.com, ask for form 68-0217-1. That will give you complete wiring & piping diagrams to check out. Let me know if this helps.