 02-26-2012, 12:32 PM | | New Guest | | Join Date: Feb 2012 Posts: 1 |
| | blower motor speed
I really don't have a vast knowledge about HVAC systems, I know very little. Maybe someone can help me out. I have a York air handler...model number "ahe36c3xh21". My outside unit is a Luxaire LX Series TCJF Model (which is also 3 ton). What I would like to know is how do I go about finding out what the minimum speed I can set the blower motor to, because the pressure that comes out of the ducts is way too high for me. Is it possible that if the speed is set too low that it could cause damage to the system? Is there more information that is needed? I appreciate any and all input Thanks |  02-26-2012, 12:37 PM |  | Global Moderator | | Join Date: May 2000 Location: Indianapolis, IN, USA Posts: 29,076 |
| | Really you need a tech with some way of measuring duct static pressure before changing speeds. Odds are, the dealer left it on high (out of 5 speeds) which depending upon how restrictive your duct system and filter are, could be a bit much for a 3 ton A/C. But there's a big drop going to speed 4 and if the ducts are really restrictive, that could be too little for a 3 ton. Sounds like the unit is oversized or underducted. I'd have the installer out, again making sure the tech has the manometer or magnahelic for checking duct static and have them adjusted it properly. |  02-26-2012, 12:43 PM |  | Professional Member* | | Join Date: Jul 2004 Location: Massachusetts Posts: 6,121 |
| The motor speed taps are used for setting speed but the real questions remain unanswered. You didn't say whether you're heating or cooling and if heating is it by heat pump or hydro-air? Minimum airflow requirements are generally needed for the equipment side of things, particularly heat pumps and air conditioners and yes, you could do damage if the speed is set too low. The noises you're hearing are the result, as you've already deduced, of high airflow/velocity. Changing blower speeds can have many varied results, among them changing the actual static pressure of the system. This could lead to actually moving MORE air with a slower blower, something that is counter intuitive but is related to aerodynamics. Lower speed, much less resistance to airflow = more gross airflow. If you were my client, the first thing I'd need to do is a load analysis to find out if the equipment is properly sized. If yes, then we would proceed to static pressure testing in conjunction with a comparison of a proper Manual 'D' design against what you have in your home. Likewise, Manual 'T' could be of assistance at just relieving the restrictions imposed by supply outlets and grilles having lower free airspace. We recently reduced the noise in a clients master bedroom because the face velocity on the supply outlets was too great. We changed the outlets to a different style and the results were striking, the customer happy and all at minimum cost. So in your case, I'd recommend someone who really knows airflow and is familiar with the various supply outlets (diffusers and registers) and return grilles. __________________ If YOU want change, YOU have to first change. If you are waiting for the 'other guy' to change first, just remember, you're the 'other guy's' other guy. To continue to expect real change when you keep acting the same way as always, is folly. Won't happen. Real change will only happen when a majority of the people change the way they vote! |  02-26-2012, 01:44 PM |  | Global Moderator | | Join Date: Jan 2004 Location: Lancaster PA Posts: 56,824 |
| | Good chance your duct work is under sized for a 3 ton unit. Or, your 3 ton unit is over sized for your duct system, and house. | | Thread Tools | | | | Display Modes | Linear Mode |
Posting Rules | You may not post new threads You may not post replies You may not post attachments You may not edit your posts HTML code is Off |
| |
| Notices | There are two types of New Guest, those in our industry and those who come here for assistance. "PLEASE" read the SITE RULES before you post. I recommend you look at the way the site is set up and see how it flows. New Guest seeking assistance with their equipment should read the POSTING RULES. For New Guest in our industry... PLEASE CLICK HERE before you post in the AOP area. For a complete list of our Site and Individual Forum Rules... Please CLICK HERE For all... Please keep in mind...THIS IS NOT A DIY SITE. Please do not ask DIY repair instructions and expect an answer. Thank you, HVAC-Talk.com |
| AOP Residential HVAC FOR EQUIPMENT OWNERS ONLY Questions and discussions pertaining to HVAC for the home. No pricing, no DIY, please read Site Rules Register |
| |
|
0 comments:
Post a Comment