Dirty filter safety?

[midhvac]

I've been thinking about creating some kinda setup for rental properties which would disable the system if the filter doesn't get changed.

Maybe like a pressure control which would either sense a high static drop across the filter or maybe one which would be in the blower compartment and wouldn't even need a hose. It would just open or close the contacts when the negative static pressure in the blower compartment got too high.

Seems like it would either have to have a time delay, so it wouldn't short-cycle the unit, or it could have a lockout relay setup, so that the system control voltage would have to be reset. Obviously it would be wired through control voltage.

What are your thoughts on this?

How would you prefer it be done?

[will 2]

Originally posted by midhvac
What are your thoughts on this?
Just one...
http://www84.pair.com/waw/Mine/Animation2.gif

[Senior Tech]

They already have a safety...high limit switch. Just kidding, I know what your saying but the owners would just get frustrated at the service call fee for going to a no heat for the purpose of just having to reset the safety and change the filter...we know it would save money overall on furnace damage but owners of rental property seem to think short term when it comes to $$$.

[midhvac]

I've got a call right now, and I know what's wrong with it before I even go there. Every fall this dipstick renter calls with no heat. The unit ices up towards the end of summer because he won't change the filter which just slides into a slot. Water goes down through the furnace, knocks out the pilot and fries the motor. The landlord even provides him with a box of filters.

[otto]

Just got back from an "emergency" call. 3 Kewanee boilers for a 15 story high rise Senior home. Anyhows, I can just imagine the scenario that led up to the service call. Manager sees the weather forecast for 30° tonight and asks the maintenance guy to go check that the boilers are working. These are on a Heat Timer control for Indoor/Outdoor reset. It's 52° outdoors when I get there and the heat is NOT CALLING!!!! The maint guy says it's boiler # 1 not coming on. No alarm, no lock-out. #3 is set as lead boiler. I try to explain staging and I/O reset control and also tell him that there's nothing wrong. Oh well, they'll get billed for it and maybe next time won't call me out on a Sunday afternoon to look at boilers that shouldn't be on anyway. Took me an hour each way to do the call and another 1/2 hr to make sure all was OK.

As for the original post, many people are technically illiterate and won't stop to think. They wouldn't try to change a filter if their life depended on it.

I do remember some of those old nylon mesh washables had a whistle embedded in the center and when the filter got dirty enough, the air would go through the whistle to let you know to wash it. I thought it was a good idea but I guess it would just be a service call on Sunday afternoon, just when you're gonna take a nap or get horizontal with the wife. "There's a strange noise coming from my furnace. Please come out and check it. I turned the power off."

[Edited by otto on 10-17-2004 at 07:17 PM]

[midhvac]

Originally posted by will 2

Originally posted by midhvac
What are your thoughts on this?
Just one...
http://www84.pair.com/waw/Mine/Animation2.gif

Oddly enough, I had thought of wiring up a 115 decibel synthesized voice that said something similar!!

Maybe all of this hi tech stuff is getting the best of us? :D

Here's something I actually did at a rental property where the evaporator was freezing up in the attic from a dirty filter and ruined the the whole ceiling below.

I wired in a refrigeration cold control into the Y circuit, set it at 48 degrees, put the remote sensing bulb in the supply duct and wired in a time delay. The owner authorized it and has been very happy ever since.


[Edited by midhvac on 10-17-2004 at 08:18 PM]