Heat Loss based on utility bills.

[motoguy128]

Each zone needs to have enough ductwork to handle the cfm needed to maintain temp at design conditions and should also have enough to handle minimum airflow of the equipment, but I infinity will dump to other zones if needed. So if heat loss is calculated at 8000btu for the smallest zone, in design conditions the hp puts out let's say 10000 btu at 350cfm then it needs to handle 350cfm. An ideal design would be 700 feet per min for the supply branches, so that's 101 Sq inches of duct area. A single 10in branch or two 8" ducts and a pair of 6x12 registers with higher quality registers. The really cheap stamped steel are very restrictive and have poor throw.

I e good rule is to size the whole system as normal then bump up ductwork by 1/3 to each zone.


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[JimmyP]

Ok thanks for that information.

[JimmyP]

Anyone have an opinion on the Infinity Greenspeed vs the Nordyne FT4BG?

Thanks

[dan sw fl]

Anyone have an opinion on the Infinity Greenspeed vs the Nordyne FT4BG?

Thanks

I'd say " The glass is Way More Than Half Full " on Both.

http://more-than-half-full.com/

[JimmyP]

I'd say " The glass is Way More Than Half Full " on Both.

http://more-than-half-full.com/

Thanks Dan

Interesting reading and a good way to be.

I gather that both are better than good equipment. Now only if I knew my caculations were correct and a 2 ton is all i need.

Jimmy

[dan sw fl]

Thanks Steve

I did a load caculation using the HVAC Calc software and I came up with ~ 21000 BTU's/hr.

Right now I only have the propane and 5 Kw of baseboard heater and it heats fine.

Jimmy {POST # 3}

IT'S AN ABSOLUTE _ NO BRAINER _ TO ADD A 2-TON GREENSPEED.
_______ ___________ __________ __________________
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv vvvvvvvvvvvvvvvv

It will handle > 99% of the heat loss.

[motoguy128]

IT'S AN ABSOLUTE _ NO BRAINER _ TO ADD A 2-TON GREENSPEED.
_______ ___________ __________ __________________
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv vvvvvvvvvvvvvvvv

It will handle > 99% of the heat loss.

I haven't heard very good things about the Nordyne controller. Infinity control is still one of the best out there. Especially with zoning. Their logic for airflow to help control humidity is pretty impressive. A properly sized unit in an average home can maintain humidity level very precisely even in low load conditions, unless it's a cloudy day or early morning with cooler temps.

[JimmyP]

IT'S AN ABSOLUTE _ NO BRAINER _ TO ADD A 2-TON GREENSPEED.
_______ ___________ __________ __________________
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv vvvvvvvvvvvvvvvv

It will handle > 99% of the heat loss.

Ok Great.


Thanks!

[JimmyP]

I haven't heard very good things about the Nordyne controller. Infinity control is still one of the best out there. Especially with zoning. Their logic for airflow to help control humidity is pretty impressive. A properly sized unit in an average home can maintain humidity level very precisely even in low load conditions, unless it's a cloudy day or early morning with cooler temps.

Thanks

I have read the lower 19SEER FT4BG can use a 2 stage controller( honeywell or others) and I was recommended Azrel zoning with it. It says can have 5 stages in heating and cooling.


The IQ drive controller is needed for theFT4BI.

They both have the modulating inverter compressor. I think the FT4BI is double the cost.


Jimmy

[motoguy128]

Arzel zoning is good, but with Infinity it will be fully modulating with both the equipment and zone dampers. 5 stages is nice, but a full range of 35-100% is definitely better. So if zones 1 & 2 need 200 CFM each and zone 3 is unoccupied and zones 4 needs 100 CFM to maintain temperature, the system will run at a speed to deliver 500CFM. IF its' lets say about 30F outside and airflow is on comfort, that would be I think roughtly 70% capacity. No, it's night time and zone 2 also goes unoccupied, but it's now 20F outside, so it's 325CFM total, so it's now lets say 45% capacity. It slowly cools off overnight. The airflow rises by about 5 CFM for each 1% the compressor setpoint is raised. No step shifts, just like a modulating furnace.

[JimmyP]

Arzel zoning is good, but with Infinity it will be fully modulating with both the equipment and zone dampers. 5 stages is nice, but a full range of 35-100% is definitely better. So if zones 1 & 2 need 200 CFM each and zone 3 is unoccupied and zones 4 needs 100 CFM to maintain temperature, the system will run at a speed to deliver 500CFM. IF its' lets say about 30F outside and airflow is on comfort, that would be I think roughtly 70% capacity. No, it's night time and zone 2 also goes unoccupied, but it's now 20F outside, so it's 325CFM total, so it's now lets say 45% capacity. It slowly cools off overnight. The airflow rises by about 5 CFM for each 1% the compressor setpoint is raised. No step shifts, just like a modulating furnace.

That sounds really nice. Should be way more efficient too.

[motoguy128]

With a zoning system, modulating equipment is ideal so that you can maintain a constant CFM to each zone as needed to cool the space, rather than simply proportioning the airflow across the zones or wit ha more simplistic zone system, cycling the equipment based on binary calls. Any system that measures temrpature in each zone rather than requesting to be heated or cooled has an advantage because it can anticipate demand. Its more of a feed forward system rather than a reactive system.

[JimmyP]

Update on Heat Pump

I had a 18000 Mini split installed on the main floor and it is heats the house without any problems,even when the temperature is at 7F which is the design temp for this area.