HVAC recommendations

[scott711]

Does anyone on the board recommend a good HVAC tech? 

 

I am trying to fix the humidity in my basement.  I just had a tech come out to do the yearly maintenance on our furnace. I was asking what he recommends and all he wanted to do was get me to spend thousands of dollars on various efforts and it didn't seem like he had much experience dealing with this issue.

 

He was concerned because there was some rust from when my tank flooded part of the basement and that the humidistat that he just put in 10 months ago had a rusted circuit board.

 

I had a couple of ideas that i was thinking of doing (I attached a diagram of my basement area):

 

Run a return to the tank room

Run a supply to the tank room

Run an inline fan into the gas vent ductwork (not sure if this is a good idea)

Run an inline fan from the fish room to outside (have to drill through concrete and not sure how to do that correctly.)

 

Any help would be greatly appreciated!  My wife keeps saying to get rid of the tank :(

 

 

[ridetheducati]

Scott,

 

You may have addressed this already in another thread, but did you try a dehumidifier?

[scott711]

yes, i have one, but I want to limit how much it runs since it is an energy hog.

[rebekwl]

Okay so first off the exhaust to the flue is a very bad idea, don't do it. Now, adding a return will help however you will need to run your blower motor constantly to have an effect.. is it variable speed? If not you will still see an increase in energy cost.. but it may still be less than running the dehum.. don't add a supply to that room either you are trying to dehumidify the space and conditioned air while having some dehumidification attributes still contains way more humidity than the standard air within the home what you'd like to do is close of the supply air to the basement completely and add the return to the fish room this should change your situation. I personally think that if you're not going to add a a whole home dehumidifier then you still going to want to run the dehumidifier for that room from time to tim.

 

Hvac service mechanic 10 plus years

Edited June 21, 2013 by rebekwl

[scott711]

I don't think the house fan is variable speed.  It is either on/off/auto.  I don't think we would do the whole house dehumidifier since we will be moving in a year, but that is an option.

What about installing an inline fan and venting it outside?

[rebekwl]

you have to check the square footage of that room and make sure that the inline fan or a bathroom exhaust fan if you will as correct amount of CFM's that would make a difference but it is an option I would think going with the return from the actual duct if its cessible would be easier than going to the block wall with an exhaust fan...

[rebekwl]

also adding the return line directly from the ductwork means that every time the AC runs it will be pulling that humid air and dehumidifing it across the coil

[scott711]

also adding the return line directly from the ductwork means that every time the AC runs it will be pulling that humid air and dehumidifing it across the coil

 

Isn't that what I want?

[rebekwl]

Yep

[rebekwl]

Go10" or larger make sure to use a filter grille

[linkfalcon]

U could also do a in wall unit.

I'd look at doing a exhaust fan in the room controlled by a humidist with a ECM fan

[linkfalcon]

NEVER tie into flue pipes

[ToddR]

I had the same problem in my basement. I used a high capacity low sone bathroom fan vented to the outside. This still might not be an option for you if the exit is through masonary. Just a thought.

[Coral Hind]

There was mention above of adding a return into the room. It sounds like his water heater and furnace, which both sound like they are not a closed loop or direct vent type, are in this space. Adding a return to the duct could create a negative pressure in this area drawing in possible CO gas. If a return is added then a vent from the main basement area into the fish room must be added to prevent any negitive pressure. Or,adding a supply would send already cooled and some what dehumidified air to the fish room. The now pressurized fish room would release pressure up the water heater vent or out into the basement area where it would eventually make it back into the HVAC unit. Either way a vent from the fish room to the main basement area should be made. Cutting the bottom of the door to allow air flow may be all that is needed. You just need to allow that free flow of air to prevent any pressure issues.

[Coral Hind]

I had the same problem in my basement. I used a high capacity low sone bathroom fan vented to the outside. This still might not be an option for you if the exit is through masonary. Just a thought.

 

If you have gas hot water or heat this can cause a bad situation if it draws air back down the vent pipes. It depends on how the heaters are vented. If you have gas units make sure to have a CO detector.

[scott711]

There was mention above of adding a return into the room. It sounds like his water heater and furnace, which both sound like they are not a closed loop or direct vent type, are in this space. Adding a return to the duct could create a negative pressure in this area drawing in possible CO gas. If a return is added then a vent from the main basement area into the fish room must be added to prevent any negitive pressure. Or,adding a supply would send already cooled and some what dehumidified air to the fish room. The now pressurized fish room would release pressure up the water heater vent or out into the basement area where it would eventually make it back into the HVAC unit. Either way a vent from the fish room to the main basement area should be made. Cutting the bottom of the door to allow air flow may be all that is needed. You just need to allow that free flow of air to prevent any pressure issues.

 

My knowledge in HVAC is very minimal, but the water heater and furnace both pull air from inside and vent the co2 to the roof. I still am getting confused as to the exact definition of a return vs. a supply ( does return = supplies air to the house and the supply = provides air to the Unit?)

 

Their are two supplies to the furnace, one is in a stairwell and the other is upstairs. I am pretty sure the type of furnace I have is forced air.  The Condensing Unit is outside.  The fish room has no door and has access from the other side so it is in no way sealed from the basement.  The only door in the living area is near the washer/dryer and that door is never closed.  I got a hygrometer and at the highest it gets 64% in the fish room and the lowest is 53%.  I have an LG dehumidifier next to the washing machine. 

 

My plan is to install a vent connected to the AC(supply or return based off of the correct definition) that pulls air from the room to help circulate it to the rest of the house.

[Coral Hind]

 ( does return = supplies air to the house and the supply = provides air to the Unit?)

Swap that. Supply puts air into the room, Return allows air back to the unit.

[Coral Hind]

My plan is to install a vent connected to the AC(supply or return based off of the correct definition) that pulls air from the room to help circulate it to the rest of the house.

Since there is no door, good info to know, and everything is wide open there is no chance of a negative pressure being created by you adding in vent.