The 4 ton and 3 ton bids are using the same design temperatures of -4 and 93 degrees. Also the average internal gains are very different. 3 ton is 7793 and 4 ton is 12692.

As far as the pumps, everyone in the area sells WaterFurnace, GeoComfort, or Climate Master.

We are going to talk to three of the four bidders and ask that they explain why eveything is so different as far as numbers.

Just Curious, are these the only major vendors for Geothermal systems? Does anyone have a complete list of manufactors?

See this post

McQuay is not on the list so I know it is not complete

What brand is yours?

Hey geodean. We downloaded the software you pointed us to, took the 10 minute video, and are now plugging in the numbers. They certainly ask a lot more questions than the HVAC contractors did. This program is like the Res Check we did (we are our own General Contractor) so we were pretty comfortable with all the information they were asking. We will post and let everyone know what we came up with as far as loads. This should be interesting.

thanks for the update, anxious to hear the outcome

Okay, we have run the numbers and have a question. The basement: 1800 sq ft, one daylight window and two standard 5.7 sq ft egress windows. There will be an R10 blanket on the walls. Living in Iowa the basement will have a few heat registers to keep the basement "warmer" in the winter months. In anyone's opinion would you consider the basement unheated or a conditioned space? The heat numbers go from 57,000 for unheated to 32,000 for conditioned.

In Utah, we always heat the basements. Remember that if unheated then the mainfloor is over unconditioned space which requires more heat. Did you select the below grade option for the basement walls? And there is nothing entered for the ceiling value in the basement since the mainfloor is heated.

I have a "Florida Heat Pump" FHP Manufacturing Division Model LTV-50-1  230/208v
         Compressor 230/208   Volt,    17.6 RLA,   88 LRA
         Blower          230/208   Volt,   1/2 HP,    4.1 FLA
Anyone know what any this means? I wouldn't mind getting a manual for it.

Here is a list of all the models that Florida Heat Pumps makes.   I don't see yours on there.

You can inquire about yours here .  When I asked about mine,  I did get a reply.

Did you ever confirm if yours has back up heat?   My guess is that it does.  If there is a junction box inside the upper cover, you could look in there to see if there are leads going into the air box.  Back up heat is located at the very top of the unit right below where the duct work hooks on.

Good luck and let us know.

I just can't believe that your house needs 57,000 btuh. If you will send me all of the input data, I would like to run the numbers on this myself. My house is 1700 sq ft with a basment and my heat loss is 43000 btuh.

TechGromit,

It's a 230 Volt compressor, with a run load amps (amps that it uses while running) of 17.6A, and a Locked rotor amps of 88. FLA is full load amps, or when the motor is under full load, it's drawing 4.1 amps.

Iowa Geohope, did you get my message?

TuffLuckDriller - We did receive your mesage and sent a response by private message on 2/8 and again on 2/10. Thank you.

Thank you to everyone for all the help. We have both run our own numbers and GeoDean ran numbers, all using the same program. Roughly, we all landed at 32,000 btuh heat loss. Factoring in the 20% safety margin recommended by the program we all end up at 38,400 btuh. As professional heat contractors, or any one who else who wants to weigh in on our question, would you look me in the eye and say “Go 4 ton as 3 ton is really marginal.” Iowa winters are harsh and we do end up with several below zero days a year. The last two days here have been rough with 40 mph winds and a temperature that did not get above 4 degrees. Please, all we want is an honest answer. 3 ton or 4 ton? If it were you, what would you do?

I would go with the 4 ton. My house is about the same size as yours, not quite as well insulated and I have a 4.5 ton. I didn't design my system, but I monitor very closely how it works. It keeps my house plenty warm in the winter. Cooling works well also.

There is nothing wrong with buying yourselves some peace of mind.

I would recommend a two stage heat pump, then when cooling, you can have longer run times on first stage to get better dehumidification.

Thank you for the answer. We have been vacillating over this question for several weeks. All the systems we have had bid are three stage heating and two stage cooling. After your numbers and our numbers we realized a 3 ton wasn’t going to work. Geo is the thing we are absolutely going to do. Based on all the information you have all so kindly posted, we will be talking to several HVAC contractors and challenging their heat loss numbers.

Good Luck and keep us posted.

Yep. With the numbers, I'd stick with a 4 ton.

Quote,

FHP does not make "owners manuals" or "operation & maintenance" manuals. The
only thing available would be wiring schematics but we only send them to
licensed Contractors.

Regards,

Greg Dunn
Technical Support

Well they were really helpful, NOT! That's something that really Urks me about some companies, no support. I have an electric Corona chainsaw on a pole and I go to the website for support and there zero information about it. They answered one question someone asked about it, but that's it. What would it cost them to put a PDF manual online for it? About 2 cents?  So they don't sell or make it anymore, so what, they should throw some documention online about the product under discontinued products so when I need to buy a replacement chain for it, I dont have to guess what size I need.

A geothermal system isn't a 99 dollar chainsaw, if I'm spending 20k on a geothermal system I want a friggin manual for it! Is that too much to ask? When I have to replace my system, one of the things I'll be looking at is what kind of online support they offer for what they sell / have sold.  

WaterFurnace has an impressive amount of info for there products online, I don't even own one and i see a spec catalog that lists picture of components, features, tables and wiring diagrams. What's the big secret with wiring schematics anyway, it's not like I'm going to rewire the system just for fun.   

FHP is just a lower end unit, compared to WaterFurnace. That's not to say one is better than the other, but price-wise, they are worlds apart.