Jump to content
Come try out our new Arcade we just put up, new games added weekly. Link at the top of the website ×

Any Residential HVAC Contractors Around Here? Need Some Advice


djMot

Recommended Posts


  • Member ID:  3189
  • Group:  *** Clan Members
  • Followers:  93
  • Topic Count:  355
  • Topics Per Day:  0.08
  • Content Count:  5230
  • Content Per Day:  1.18
  • Reputation:   11104
  • Achievement Points:  48729
  • Solved Content:  0
  • Days Won:  112
  • Joined:  02/11/12
  • Status:  Offline
  • Last Seen:  
  • Birthday:  12/24/1957
  • Device:  Windows

I own a rental property, a duplex built in 1976.  Mirror image, tri-level, 1400sqft, side-by-side units.  See picture.  I live on one side, rent the other.

Both furnaces are Lennox Elite Series 80+, 80% efficiency units (measured at around 87%).  One (tenant's side) was installed in about 1996.  The other was installed in 2000.  They look identical, but their motherboards are way different.  The older one has spark ignition, the newer one has glow stick ignition.

The central air systems are 2 tonne Trane units installed in 2011 on both sides.  Cost was right around $11k for the pair as I recall.

A few weeks back, my tenant texted to say the AC was unable to push the temp in the building below 77ºF.  An HVAC contractor came out to check the system over and found they needed to add 5 lbs of R410A which is close enough to the capacity of the system for them to say it was essentially dry.  As they stated, these are sealed, closed-loop systems that theoretically do not lose pressure and never need to be "topped off", so when they do, there's a leak somewhere that needs to be found.  They suggested proceeding through the summer and see what happens.  If it stops cooling at some point this summer, then there must be a massive leak.  Otherwise, the recommendation is to hack the system apart this fall, seal up the individual components, and pressurize them with nitrogen.  Next spring, look to see which has lost pressure and replace that element of the system.  Of course if it's the outside coils, forget it, the system is a complete loss and should be replaced.

Another consideration:  The furnace (being non-high efficiency unit) exhausts to a roof chimney through a 6"(?) galvanized steel flue.  Up until 2006, the water heaters joined that same exhaust, but were replaced with units that exhaust through pvc out the side of the building.  Over the subsequent years, moisture has been found to drip from the bottom of the furnace's exhaust.  I'm told the reason for this is that, because the water heaters no longer exhaust that way, condensation that would otherwise be dried by the second unit operating up that pipe is now making its way down to the bottom and dripping out, not ot mention corroding the base cap of that pipe.  Recommendation is to either get a chimney liner, or replace the furnace with high efficiency units that vent out the side of the building and abandon the old chimney altogether.

Legal concerns:  My tenants have two young boys.  Naturally, when advised there may be a coolant leak somewhere in the AC system, they wanted to know if they are in any danger from the coolant chemicals.  Looks like R410A is not classified as a hazardous material, but a tenant could still make one hell of a legal stink over something like this!

So I'm faced with what to do?  I've dumped $466usd into this already.  There's another ~$500 coming at me in the fall to break the system down for nitrogen testing.  Then there's the cost to actually replace the leaking component.  Then there's around $300 - $500 to install chimney liners to correct the condensation issues in the furnace exhaust.  Ot there's the cost to replace both furnaces with current high-efficiency units.  In an effort to maintain symmetry and not make it look like there's considerable deferred maintenance in the building, I tend to keep major systems identical between the units, so replacing something on one side usually means replacing it on both.  Two furnaces, two central air systems is what I'm possibly facing.  My guess is somethere in the area north of $18k to do it all.

Thoughts?  It's always hard to know if the local contractors are just selling you ideas that are profitable for them or best for the customer.  I'm not sure at what point I'm throwing good money after bad, or when I'm just being stupid and replacing too much.

Thanks!

 

  

 

 

20170927_132404.jpg

Link to comment
Share on other sites



  • Member ID:  23622
  • Group:  ++ COD5 Admin
  • Followers:  25
  • Topic Count:  54
  • Topics Per Day:  0.02
  • Content Count:  533
  • Content Per Day:  0.18
  • Reputation:   442
  • Achievement Points:  5619
  • Solved Content:  0
  • Days Won:  2
  • Joined:  11/25/15
  • Status:  Offline
  • Last Seen:  
  • Birthday:  01/01/1954
  • Device:  Windows

$18,000+ seems a little steep?  Seems you could get a volume discount if your doing both.  About 3 years ago I had to get a new furnace ,  I decided to ‘add’ AC as well.  On top of that our city building ordinance changed and I could only vent one item into our chimney.  Since I have a small fire place that I feed into the chimney,  I needed to vent my hot water heater another way.. Ended up getting a high efficiency water heater as well that vents thru the wall outside.  Anyway, my total cost for all was just under $8k , which included the new water heater and wiring for the new AC.   Figured I am also saving money with the higher efficiency furnace ( winter months about $20-$40 month).  Since you already have AC your wiring should be all set(No extra $)..

Since your units are older (1-over 20 years and 1-just under) ... you may still end up having to replace them sometime in the near future?  If you could get a good volume deal on 2-units and get the higher efficiency furnace  to bring heating costs down it may be something to consider.. Not sure if your renters pay for their own heat, but if their heating costs come down and they are great renters you want to keep, lower heating bills for them may help retain them ?

Link to comment
Share on other sites



  • Member ID:  87
  • Group:  ***- Inactive Clan Members
  • Followers:  57
  • Topic Count:  98
  • Topics Per Day:  0.02
  • Content Count:  3789
  • Content Per Day:  0.71
  • Reputation:   3589
  • Achievement Points:  27249
  • Solved Content:  0
  • Days Won:  7
  • Joined:  09/02/09
  • Status:  Offline
  • Last Seen:  
  • Birthday:  04/02/1871

i was a HVAC journeyman for 30+ years worked on res commercial and industrial.the age of the system might be better to replace because the the energy efficiency now 95+ furnaces don't require flue pipe but use pvc pipe that how much efficient they are same with the cooling sides efficiency's are very much higher than the units you have.i worked for train for 12yrs on ft Knox lol get more than on estimate for replacing and check them out through bbb

Edited by 7Toes
Link to comment
Share on other sites



  • Member ID:  87
  • Group:  ***- Inactive Clan Members
  • Followers:  57
  • Topic Count:  98
  • Topics Per Day:  0.02
  • Content Count:  3789
  • Content Per Day:  0.71
  • Reputation:   3589
  • Achievement Points:  27249
  • Solved Content:  0
  • Days Won:  7
  • Joined:  09/02/09
  • Status:  Offline
  • Last Seen:  
  • Birthday:  04/02/1871

oh yea if they use the old duck work and line sets that should save some money.most likely that leak is in the evap coil or in the outside condensing unit

Link to comment
Share on other sites



  • Member ID:  3189
  • Group:  *** Clan Members
  • Followers:  93
  • Topic Count:  355
  • Topics Per Day:  0.08
  • Content Count:  5230
  • Content Per Day:  1.18
  • Reputation:   11104
  • Achievement Points:  48729
  • Solved Content:  0
  • Days Won:  112
  • Joined:  02/11/12
  • Status:  Offline
  • Last Seen:  
  • Birthday:  12/24/1957
  • Device:  Windows

@7Toes - isn't there a R410A sniffer that could be used to detect a leak.  This business of hacking the system up into 4 parts and pressurizing them with nitrogen just seems so extreme!  Is that really the only cost effective way?

Link to comment
Share on other sites



  • Member ID:  87
  • Group:  ***- Inactive Clan Members
  • Followers:  57
  • Topic Count:  98
  • Topics Per Day:  0.02
  • Content Count:  3789
  • Content Per Day:  0.71
  • Reputation:   3589
  • Achievement Points:  27249
  • Solved Content:  0
  • Days Won:  7
  • Joined:  09/02/09
  • Status:  Offline
  • Last Seen:  
  • Birthday:  04/02/1871

yes there is!but when you have a leak in 410a depending on the amount loss they will have to remove whats left and refill it!because 410a is a mix of refrigerants which do not evaporate at same amounts when you have a leak which creates a imbalance.what threy might be doing is pressurizing and using a dye to see where the leak is?

 

Link to comment
Share on other sites



  • Member ID:  1213
  • Group:  *** Clan Members
  • Followers:  19
  • Topic Count:  172
  • Topics Per Day:  0.03
  • Content Count:  5348
  • Content Per Day:  1.04
  • Reputation:   13963
  • Achievement Points:  47085
  • Solved Content:  0
  • Days Won:  174
  • Joined:  03/04/10
  • Status:  Offline
  • Last Seen:  
  • Birthday:  10/11/1961
  • Device:  iPad

First thing they should have sniff tested the high and low side ports to make sure that’s not where the leak is , most common place in a sealed system.  The dripping of the exhaust flue is really odd.  Even with out the other clues it should not be condensing like that.  Is there a moisture source near by that is being drawn into the exhaust when the furnace is running.  Have had one do the same thing that was installed in the laundry closet. When the dryer exhaust had it’s own ducting.  But had been damaged a little so when it ran it raised the moisture level just a bit in the closet.  With just natural drafting it would condense on the cool sheet metal of the ductwork and drip for the furnace. 

Link to comment
Share on other sites



  • Member ID:  221
  • Group:  ***- Inactive Clan Members
  • Followers:  11
  • Topic Count:  85
  • Topics Per Day:  0.02
  • Content Count:  1864
  • Content Per Day:  0.35
  • Reputation:   745
  • Achievement Points:  12302
  • Solved Content:  0
  • Days Won:  0
  • Joined:  09/04/09
  • Status:  Offline
  • Last Seen:  
  • Birthday:  06/10/1967
  • Device:  Windows

I have done Residential,Commercial,Industriral, A/C for 35+ years and they should have done a quick leak test. (atleast That's what I would have Done). anyways. with the age of the furnaces I would suggest you get multiple bids and see about getting both systems replaced . since they both already use R-410a you should not have to replace line sets. I would flush line sets and  install filter driers . OR Have them come back now and preform a extensive leak check to a sure your residents that there  is no hazard . 

Link to comment
Share on other sites



  • Member ID:  842
  • Group:  *** Clan Members
  • Followers:  62
  • Topic Count:  278
  • Topics Per Day:  0.05
  • Content Count:  3712
  • Content Per Day:  0.71
  • Reputation:   3150
  • Achievement Points:  28451
  • Solved Content:  0
  • Days Won:  4
  • Joined:  12/06/09
  • Status:  Offline
  • Last Seen:  
  • Birthday:  05/04/1965
  • Device:  Windows

DJ,

The systems are old but that doesn't make them bad....they can shoot some dye into the system and come back in a week or 2 and use ultraviolet light to locate the leak...after that should be a quick repair. At least thats how we do it here....and if they are going to evacuate the system to fix a leak have them change the filter dryer..

Also if the leaks are minor enough that it needs a charge every couple of years they also make a sealant. Obviously new equipment has the benefits of new technology and warranty but if your not looking to spend it, then fix it.

Link to comment
Share on other sites



  • Member ID:  842
  • Group:  *** Clan Members
  • Followers:  62
  • Topic Count:  278
  • Topics Per Day:  0.05
  • Content Count:  3712
  • Content Per Day:  0.71
  • Reputation:   3150
  • Achievement Points:  28451
  • Solved Content:  0
  • Days Won:  4
  • Joined:  12/06/09
  • Status:  Offline
  • Last Seen:  
  • Birthday:  05/04/1965
  • Device:  Windows

On 5/25/2019 at 7:07 AM, djMot said:

ver the subsequent years, moisture has been found to drip from the bottom of the furnace's exhaust.  I'm told the reason for this is that, because the water heaters no longer exhaust that way, condensation that would otherwise be dried by the second unit operating up that pipe is now making its way down to the bottom and dripping out, not ot mention corroding the base cap of that pipe.  Recommendation is to either get a chimney liner, or replace the furnace with high efficiency units that vent out the side of the building and abandon the old chimney altogether.

In the heating season?? If dampness occurs in the cooling season its condensate from the coil not draining properly.

Link to comment
Share on other sites



  • Member ID:  3189
  • Group:  *** Clan Members
  • Followers:  93
  • Topic Count:  355
  • Topics Per Day:  0.08
  • Content Count:  5230
  • Content Per Day:  1.18
  • Reputation:   11104
  • Achievement Points:  48729
  • Solved Content:  0
  • Days Won:  112
  • Joined:  02/11/12
  • Status:  Offline
  • Last Seen:  
  • Birthday:  12/24/1957
  • Device:  Windows

On 5/26/2019 at 9:53 AM, 7Toes said:

yes there is!but when you have a leak in 410a depending on the amount loss they will have to remove whats left and refill it!because 410a is a mix of refrigerants which do not evaporate at same amounts when you have a leak which creates a imbalance.what threy might be doing is pressurizing and using a dye to see where the leak is?

 

The guy did mention dye testing, but that it's generally difficult to use to spot leaks in certain locations.  I think he was mainly referring to trying to use a UV light outside around the valves and compressor coils.  Sounded like he didn't want to go there.

Link to comment
Share on other sites



  • Member ID:  3189
  • Group:  *** Clan Members
  • Followers:  93
  • Topic Count:  355
  • Topics Per Day:  0.08
  • Content Count:  5230
  • Content Per Day:  1.18
  • Reputation:   11104
  • Achievement Points:  48729
  • Solved Content:  0
  • Days Won:  112
  • Joined:  02/11/12
  • Status:  Offline
  • Last Seen:  
  • Birthday:  12/24/1957
  • Device:  Windows

On 5/26/2019 at 10:32 AM, bds1961 said:

First thing they should have sniff tested the high and low side ports to make sure that’s not where the leak is , most common place in a sealed system.  The dripping of the exhaust flue is really odd.  Even with out the other clues it should not be condensing like that.  Is there a moisture source near by that is being drawn into the exhaust when the furnace is running.  Have had one do the same thing that was installed in the laundry closet. When the dryer exhaust had it’s own ducting.  But had been damaged a little so when it ran it raised the moisture level just a bit in the closet.  With just natural drafting it would condense on the cool sheet metal of the ductwork and drip for the furnace. 

About the only thing I can think of is that I had the roof replaced in 2014.  Although the water heater was replaced in 2006 and there may have been some drippage between then and 2014, it seems like it became really noticeable after 2014.  That might have just been coincidence as the corrosion became more obvious over time. 

The new roof replaced old-style pot vents with ridge vents.  That may have changed the temperature profile of the last 8' of chimney flue.  Maybe that has caused increased condensation.  The chimney enclosure is galvanized steel box originally made to look like brick, but painted a dark mocha brown when the roof was being replaced.  That could change the temperature profile in the last few feet of the flue.  Other than that, there's no new source of moisture in the area.

Link to comment
Share on other sites



  • Member ID:  3189
  • Group:  *** Clan Members
  • Followers:  93
  • Topic Count:  355
  • Topics Per Day:  0.08
  • Content Count:  5230
  • Content Per Day:  1.18
  • Reputation:   11104
  • Achievement Points:  48729
  • Solved Content:  0
  • Days Won:  112
  • Joined:  02/11/12
  • Status:  Offline
  • Last Seen:  
  • Birthday:  12/24/1957
  • Device:  Windows

19 hours ago, deerejon said:

In the heating season?? If dampness occurs in the cooling season its condensate from the coil not draining properly.

Yes, in the heating season.  Not in the cooling season.  And I'll go out on a little bit of a limb here and say it seems more prevalent when there's been snow storms.  Although the flue is capped in the same manner it has been since its installation, the flue temperatures have probably changed over time with the replacement or elimination of equipment connected to the flue.  Maybe that has caused an increase of ice formation from combustion condensation combined with fine snow flakes blowing in under the cap forming a rim of ice that thaws and freezes as the furnace cycles?  idk.  The corrosion and drippage is ugly, though.  Stains the floor.  Looks all rusty and crusty at the bottom of the flue pipe.  

Link to comment
Share on other sites



  • Member ID:  3189
  • Group:  *** Clan Members
  • Followers:  93
  • Topic Count:  355
  • Topics Per Day:  0.08
  • Content Count:  5230
  • Content Per Day:  1.18
  • Reputation:   11104
  • Achievement Points:  48729
  • Solved Content:  0
  • Days Won:  112
  • Joined:  02/11/12
  • Status:  Offline
  • Last Seen:  
  • Birthday:  12/24/1957
  • Device:  Windows

19 hours ago, deerejon said:

DJ,

The systems are old but that doesn't make them bad....they can shoot some dye into the system and come back in a week or 2 and use ultraviolet light to locate the leak...after that should be a quick repair. At least thats how we do it here....and if they are going to evacuate the system to fix a leak have them change the filter dryer..

Also if the leaks are minor enough that it needs a charge every couple of years they also make a sealant. Obviously new equipment has the benefits of new technology and warranty but if your not looking to spend it, then fix it.

I really don't want to spend the money, but at some point the concern revolves around throwing good money after bad.   At the current age of these furnaces, frequent service could suddenly become the rule.  For just myself, that would be inconvenient; for a tenant, that could become a legal issue aimed at me.

The leaking AC already has them on edge.  They have two young boys.  This is not a good situation for me.  Suddenly scheduling a complete HVAC replacement for them would be a serious inconvenience for a day or two, but would restore confidence, peace of mind, and make me look like a hero.  that is until they get notification of their rent increase for 2020!  

Only serious bummer is that this is always a X2 operation since this is a duplex.  Although my AC is working perfectly, it would probably be replaced anyway.  This is simply a matter of keeping both units in sync as far as major mechanicals are concerned.  To a potential buyer, this speaks well of the overall maintenance and upgrade policy they are buying into.  A hodgepodge of systems makes it look like JIT and deferred maintenance is the rule.  That invites haggling over negative perceptions.

Link to comment
Share on other sites



  • Member ID:  23498
  • Group:  ++ Minecraft Admin
  • Followers:  12
  • Topic Count:  106
  • Topics Per Day:  0.03
  • Content Count:  700
  • Content Per Day:  0.23
  • Reputation:   229
  • Achievement Points:  5750
  • Solved Content:  0
  • Days Won:  1
  • Joined:  11/12/15
  • Status:  Offline
  • Last Seen:  
  • Device:  Linux

line both  chimney's s as most code wants that done especially if you decide to sell it. fix the tennant's ac leak if it loses pressure this year and then you can save up for the dual replacement in the future. fixing stuff looks good on the sale also ;)

Link to comment
Share on other sites


Guest
This topic is now closed to further replies.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.