DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Off Topic (
-   -   dual zone to single zone question (

cpifer 09-12-2010 04:35 PM

dual zone to single zone question
We have a 2200 square foot home with 1900 square feet of cooling/heating area. The house was built in 2003 and has 2 zones on one 3 ton HVAC. We need to replace it and the installer is recomending one 5 ton HVAC (RUUD) and converting to a single zone. Is this a good idea to go from a dual zone to a single zone in a 1 story house?

beenthere 09-12-2010 04:48 PM

Its a good idea, if you want higher electric bills, and higher humidity in your house.

Look for other contractors.

cpifer 09-12-2010 05:00 PM

dual zone to single zone
Is it common for a single story 2200 square foot house to have 2 zones? It really does not seem to work well for us as we can only have one zone on at a time for A/C.

beenthere 09-12-2010 05:21 PM

Its not real common. But quite a few are zoned so that they don't have to cool the bedrooms during the day, or the common areas at night while they are in bed.

Good chance yours is not installed properly. And thats why it isn't working well for you.

cpifer 09-12-2010 06:54 PM

Thank you so much for your input. We got a quote today of $11,000 (out the door) for a new RUUD (Condensor 14AJM60A01, furnace RGTC09EZAJS and coil CE60D44) 5 ton 15 SEER gas electric split system, 95% efficiency and changing dual zone to single zone. Our house is only 7 years old 2200 sq ft and we just are not sure if the tonnage is to big or if changing from dual zone to single zone will be a good idea for re-sale down the road. Our dual zone is split between living area and bedroom. If the living area zone is on the bedrooms are hot and stuffy and vise versa. We do use the rooms at waking hours as ourbedrooms are an office and a workout room. Also, since all of the rooms are on the same floor we really are not sure if the dual zone makes sense anyway. Our system does need to be replaced and we want to make sure we are making the right decision. We have another HVAC guy coming out to give us a quote tomorrow.

Red Squirrel 09-12-2010 08:05 PM

Sounds like a downgrade to me. Zones are good. Personally I would love to have 1 zone per room, and it's something I've thought of, but retrofitting this properly would not be on the cheap side. :eek:

beenthere 09-12-2010 08:28 PM

Do your own load clac to see what size unit you really need.

Hard to believe you need to increase size by 2 tons.

Do you live in Death Vally were it reaches 105 regularly.

cpifer 09-12-2010 08:53 PM

I agree. We live in Sacramento, Ca which is in northern california.

beenthere 09-13-2010 03:42 AM

You have some 100 plus days. But not many. I would think its more your duct work, then the size of your A/C.

Again. I find it hard to believe you need to increase by 2 tons.

With your temps, if your house isn't insulted well, and relatively tight. Perhaps a 1 ton increase at most.

You need someone that can check out your duct system. Just putting in a 5 ton, without duct renovation, will get you a system that doesn't cool on the milder days, and will greatly increase your electric bill.

Hot hot/warm do your rooms get when both zones are calling?

cpifer 09-14-2010 12:19 PM

Well our home is about 7 years old and in a new build tract home suburb of Sacramento. The builders are notorious for putting in undersized units for the lowest bid. On the hottest day if we have both systems on the bedrooms & living area are 80 degrees +, on a milder day 90's if we have both systems on upper 70's & stuffy in both scenarios with ceiling fans on.

First HVAC Guy (some comfort technician from large company):
- 5 ton, single zone, change duct work and no upsize needed on wiring. If we kept dual zone a 5 ton a bypass would be needed. RUUD system for $11,000.

Second HVAC guy (25 years HVAC experience, small Co. & owner of the business):
- 5 ton, keep dual zone (he liked the idea of still being able to control the zones), no duct changes needed and will need to upsize wiring. No bypass needed for 5 ton dual zone. Or replace with a 4 ton and keep everything hte same, dual zone, no wire change and no duct work changes. He said HVAC system builders installed was lso undersized it was like putting a Volkswagen engine in a Cadillac. He is giving us a quote on RUUD and TRANE, he siad it would be under $10,000.

We just dont know if the 5 ton will be to big, more noisy and cost more on our electric bill. We have gas and electric in our house. We are leaning towards 4 ton and keeping the dual zone. We have a 3rd guy coming out later this week. All of this is very confusing especially when both HVAC guys are telling us two different things.

beenthere 09-14-2010 02:41 PM

Doubt you'll need to increase to more then a 4 ton.

Before doing that though. A good system check should be done. To see if your even getting the full capacity of the 3 ton unit.

A 5 ton on your existing duct work with out a bypass, could e very loud when only 1 zone calls, and could freeze up the coil.

the next contractors that you call. Ask them if they do load calcs. if they say they don;'t need to because they can tell by experience. Tell them thank you for your time. I'll call someone else.

All times are GMT -5. The time now is 11:43 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1