40x60 metal building problems with geothermal heater

[zacholley]

When I just built the house the hvac contractor gave me a better price to do a 5 ton climatemaster geothermal unit on the house and the shop so i did both.

well I just had the shop spray foamed with 2 inches of closed cell on the ceiling and 2 inches on the walls and I am wondering if maybe up by the ridge cap if they sprayed it properly because the heater is kicking on and the unit cant warm it so the 2nd stage kicks on and runs for a really long time before getting the temp to 65degrees

I will post screenshots from both of my ecobee thermostats the house is set to 70 and the shop 65 and you can see the house doesnt turn on the 2nd stage at all i feel something is wrong.

 

[BoostAddiction]

2" of closed cell is only R13. Since we don't know your location, we can't know if that is adequate. But it probably isn't, if you are running the heat just now.

Also, a shop probably has more leaks in it, specifically from the garage doors, assuming you have them. That, and other leaks will make it harder to bring up to temp.

Finally, if the shop floor has a larger area than the home, it wouldn't be surprising to see it take a longer time to come up to temp. If so, it will coast down slower as well.

 

[zacholley]

I live in Oklahoma City the temp last night I believe was around 40-45 degree's.

the overhead doors there are 2, one is 10x10 and one is 10x12 they are both insulated doors.

the house is 2560sqft so it is larger than the shop however the ceilings are 10 and 11ft in the house where this is taller. but the house just did blown in fiberglass in the walls and ceiling it didnt have any spray foam i just figured it would be doing better than this since supposedly this foam is so much better as an air barrier.

what else am i not thinking of?

 

[couch67]

I am not a geothermal expert, but looking at your shop t-stat screenshot, just a few quick comments:

- I think with geothermal, its better to keep the t-stat set to a constant setpoint - all to avoid the 2nd stage (expensive) from kicking in when the t-stat is calling for a big change in heat. Looks like shop was set to go from 60 to 65, unless I read that incorrectly?

- Was the heat on prior to this screenshot? If first time, it might take time to get that space, including the slab, warmed up, might account for the quick dips in temperature after the heat goes off.

couch

 

[zacholley]

Well per your concern I decided to leave it set at 65 and a full 24 hours you think the concrete floor would be up to temp so to speak well it still did the same thing overnight.... it just can't seem to keep up with a single stage I think I will have the spray foam company come out to see if they can figure it out im betting the ridge cap isnt foamed i can see some brown steel up there rather than the foam.

 

[couch67]

The fluctuating internal temperature suggests heat loss. R13 should be plenty for the outside temp you currently have. Maybe the ridge as you say. I'd also go back to the contractor for some input as heating with stage 2 will cost a fortune.

 

[zacholley]

The fluctuating internal temperature suggests heat loss. R13 should be plenty for the outside temp you currently have. Maybe the ridge as you say. I'd also go back to the contractor for some input as heating with stage 2 will cost a fortune.

Thank you I will reach out to the spray foam company tomorrow and see what they say and hopefully can get them to come look at it.

 

[86turbodsl]

When you spray foam the underside of the roof decking, you don't need a ridge vent. Should all be sprayed closed.