neilly2
Silver Member
Is anybody an HVAC pro? I'm halfway through building the new house and have some key questions mostly basics, before I let out the contract on the heat and air.
HVAC Experts
- Thread starter neilly2
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BarryinMN
Platinum Member
Birdhunter1
Veteran Member
What's your question. I used to do it a few years ago.
Ray2210
Silver Member
Ask your questions. Any of us with Mechanical Engineering backgrounds can answer some of them, others may require a contractors advice.
ronjhall
Super Star Member
Here is a thread from last fall that help with HVAC decision's. Click Here
You may want to PM some of the posters in the thread.
You may want to PM some of the posters in the thread.
Scozz
Silver Member
Fire away .. send me a PM if you like. I've been in the HVAC field for 25 years now .. glad to help if I can ... Scozz
I'll be installing hydronic baseboard heat, LP fired boiler, and central AC. I would like to go as efficient as possible without wasting the upfront cost.
I've been researching pretty hard and I think I'm burnt out. I think I've learned that the HVAC systems are a little like tractors. Each person has different company loyalties based on their own experience, different requirements based on their geography, their are a few good names of equipment that are essentially equal, you should be most concerned with availability of service, and the more you spend the more you get.
1. For the AC one contractor insists that one larger unit with zone control by dampers is the better way to go then 2 separate smaller units. This goes against what most people have around here.
2. One bidder insists the upfront cost for the high end 16 or 19 SEER Trane or Carrier units is worth it. Any idea on the differential cost going from a 14 to a 19.5 SEER?
3. What activates cycling between stages in a 2 stage compressor? Is the compressor stage controlled strictly by cooling demand? Does outside air temp play into it?
4. Boiler -- I am leaning towards a high EFF. condensing boiler, but someone has recommended a conventional boiler with low temp baseboard to accomplish a similar efficiency. This one really has me cornfused.
5. As far as the condensing boiler, the consensus seems to be you can't lose with : Buderus,Veissman, or Peerless. Specifically the Veismann is top notch, but people say the cost is ridiculus, but I have no idea what the cost of one of those is. Those 3 units never seem to have a bad word said about them. Next would be Weil-McClain which people seem to either love or hate. (same reaction that grey market tractors get)
6. I was anticipating a hydronic towel warmer to heat the master bath since we won't have wall space for baseboard. Comments???
7. We may have to go with fan powered hydronic toe kick heaters in the kitchen. I hate the sound of fans blowing. Any idea of the sound rating on these things?
8. I'm anticipating an outside air intake with heat exchanger, since I went and sealed the house up like a zip lock bag without thinking ahead. Any problems to look for with this.
9. Heat will have three zones, AC two.
10. Hot water will be indirect tank, separate zone off of boiler.
11. I'm kicking around the idea of underfloor radiant in the kitchen to get rid of the toe space heater, but that might pinch the budget. Would that be a second loop off of the hot water heater? The boiler water temp would be to hot.
12. I would love to be able to afford that $5000 heated toilet.
14. I will only install sheetmetal duct as opposed to the fiberglass board.
15. Everyone is quoting 5 thermostats (2 AC, 3 Heat). Isn't their a stat or controller that can control the heat and A/C both in the common zone?
Any thoughts or comments are appreciated.
I've been researching pretty hard and I think I'm burnt out. I think I've learned that the HVAC systems are a little like tractors. Each person has different company loyalties based on their own experience, different requirements based on their geography, their are a few good names of equipment that are essentially equal, you should be most concerned with availability of service, and the more you spend the more you get.
1. For the AC one contractor insists that one larger unit with zone control by dampers is the better way to go then 2 separate smaller units. This goes against what most people have around here.
2. One bidder insists the upfront cost for the high end 16 or 19 SEER Trane or Carrier units is worth it. Any idea on the differential cost going from a 14 to a 19.5 SEER?
3. What activates cycling between stages in a 2 stage compressor? Is the compressor stage controlled strictly by cooling demand? Does outside air temp play into it?
4. Boiler -- I am leaning towards a high EFF. condensing boiler, but someone has recommended a conventional boiler with low temp baseboard to accomplish a similar efficiency. This one really has me cornfused.
5. As far as the condensing boiler, the consensus seems to be you can't lose with : Buderus,Veissman, or Peerless. Specifically the Veismann is top notch, but people say the cost is ridiculus, but I have no idea what the cost of one of those is. Those 3 units never seem to have a bad word said about them. Next would be Weil-McClain which people seem to either love or hate. (same reaction that grey market tractors get)
6. I was anticipating a hydronic towel warmer to heat the master bath since we won't have wall space for baseboard. Comments???
7. We may have to go with fan powered hydronic toe kick heaters in the kitchen. I hate the sound of fans blowing. Any idea of the sound rating on these things?
8. I'm anticipating an outside air intake with heat exchanger, since I went and sealed the house up like a zip lock bag without thinking ahead. Any problems to look for with this.
9. Heat will have three zones, AC two.
10. Hot water will be indirect tank, separate zone off of boiler.
11. I'm kicking around the idea of underfloor radiant in the kitchen to get rid of the toe space heater, but that might pinch the budget. Would that be a second loop off of the hot water heater? The boiler water temp would be to hot.
12. I would love to be able to afford that $5000 heated toilet.
14. I will only install sheetmetal duct as opposed to the fiberglass board.
15. Everyone is quoting 5 thermostats (2 AC, 3 Heat). Isn't their a stat or controller that can control the heat and A/C both in the common zone?
Any thoughts or comments are appreciated.
Birdhunter1
Veteran Member
Why would you want to go with a boiler?
Seriously if your house is sealed up like a Ziploc bag and you're looking at actually needing a fresh air intake system you are an ideal candidate for a geothermal system.
Geothermal will work in any climate efficiently as long as the house is sealed up tight and insulated well, which it sounds as if yours is.
Geothermal costs will nto be more expensive than a zoned boiler system AND a zoned A/C system or 2 a/c system.
Good call on the sheetmetal duct, make sure and use it on the round piping (from the truck line ot the registers) as well instead of flexible duct!
Seriously if your house is sealed up like a Ziploc bag and you're looking at actually needing a fresh air intake system you are an ideal candidate for a geothermal system.
Geothermal will work in any climate efficiently as long as the house is sealed up tight and insulated well, which it sounds as if yours is.
Geothermal costs will nto be more expensive than a zoned boiler system AND a zoned A/C system or 2 a/c system.
Good call on the sheetmetal duct, make sure and use it on the round piping (from the truck line ot the registers) as well instead of flexible duct!
RE: 2. One bidder insists the upfront cost for the high end 16 or 19 SEER Trane or Carrier units is worth it. Any idea on the differential cost going from a 14 to a 19.5 SEER?
The operating cost will be roughly proportional to the inverse of the ratings. The 14 SEER unit will require about 50% more electricity to run than the 19.5 SEER for the same cooling load. If your air conditioning is $100 per month with the 19.5 SEER, it will be about $150 with the 14 SEER. If the 19.5 SEER system costs $1000 more, it will take 20 months of cooling to make up that cost differential (with the above numbers).
This assumes an ideal installation and conditions that match the test conditions. As they, "your actual mileage may vary".
RE: 3. What activates cycling between stages in a 2 stage compressor? Is the compressor stage controlled strictly by cooling demand? Does outside air temp play into it?
I would think that you need a 2-stage capable control system or thermostat to activate the two stages, but it may be that the air handler can do the control based on an internal algorithm based on how long the T-stat calls for cooling.
4. Boiler Temp
You can add an inxepensive tempering / mixing valve or a more sophisticated mixing system to generate lower temp water out of a higher temp boiler. A Reset controller can also cycle the boiler to any desired temp, assuming the boiler is a condensing unit, it won't care. Some control system run the boiler at one temp when a radiant or baseboard zone demand heat and another temp for higher-temp zones like indirect hot water production.
5. Boiler
I have a Carrier condensing Boiler that I am very happy with. I think its actually made by Dunkirk.
RE: 6. I was anticipating a hydronic towel warmer to heat the master bath since we won't have wall space for baseboard. Comments???
I considered a heated towel bar in our bathroom, but with the under-floor radiant, forced air, and gas fireplace in there, it gets warm enough!
RE: 8. I'm anticipating an outside air intake with heat exchanger, since I went and sealed the house up like a zip lock bag without thinking ahead. Any problems to look for with this.
I think this is required by code these days.
The operating cost will be roughly proportional to the inverse of the ratings. The 14 SEER unit will require about 50% more electricity to run than the 19.5 SEER for the same cooling load. If your air conditioning is $100 per month with the 19.5 SEER, it will be about $150 with the 14 SEER. If the 19.5 SEER system costs $1000 more, it will take 20 months of cooling to make up that cost differential (with the above numbers).
This assumes an ideal installation and conditions that match the test conditions. As they, "your actual mileage may vary".
RE: 3. What activates cycling between stages in a 2 stage compressor? Is the compressor stage controlled strictly by cooling demand? Does outside air temp play into it?
I would think that you need a 2-stage capable control system or thermostat to activate the two stages, but it may be that the air handler can do the control based on an internal algorithm based on how long the T-stat calls for cooling.
4. Boiler Temp
You can add an inxepensive tempering / mixing valve or a more sophisticated mixing system to generate lower temp water out of a higher temp boiler. A Reset controller can also cycle the boiler to any desired temp, assuming the boiler is a condensing unit, it won't care. Some control system run the boiler at one temp when a radiant or baseboard zone demand heat and another temp for higher-temp zones like indirect hot water production.
5. Boiler
I have a Carrier condensing Boiler that I am very happy with. I think its actually made by Dunkirk.
RE: 6. I was anticipating a hydronic towel warmer to heat the master bath since we won't have wall space for baseboard. Comments???
I considered a heated towel bar in our bathroom, but with the under-floor radiant, forced air, and gas fireplace in there, it gets warm enough!
RE: 8. I'm anticipating an outside air intake with heat exchanger, since I went and sealed the house up like a zip lock bag without thinking ahead. Any problems to look for with this.
I think this is required by code these days.
