Bosch Bova Heat pump "Adaptive capacity output"

[Poodle Head Mikey]

Oh; that's not very conclusive then.

Maybe the coil setpoint was left at 47º instead of 37º ? Or maybe the airflow volume was too high for the building's heat gain? Or both. <g>

I doubt they would out-dehumidify a Unico - with it's 32-33º six pass evap - but I would expect that when properly setup these Bosch's would be substantial performers.

I keep asking about people's experiences with them because I have yet to install one.

PHM
---------

Pretty simple, the unit(s) were touted as being able control humidity like no other unit could. Both houses I was in had RH> 60% with dry bulb temps in the mid to low 70’s. < 400 CFM PT.

I put a bucket under the white pipe and got less than 6 pounds of water after an hour of run time.

I was expecting > 10.

Non-invasive test.

[opey456]

Oh; that's not very conclusive then.

Maybe the coil setpoint was left at 47º instead of 37º ? Or maybe the airflow volume was too high for the building's heat gain? Or both. <g>

I doubt they would out-dehumidify a Unico - with it's 32-33º six pass evap - but I would expect that when properly setup these Bosch's would be substantial performers.

I keep asking about people's experiences with them because I have yet to install one.

PHM
---------

What was the problem with the bosch unit in the end? Faulty control board?

[khoff99]

Hey guys, new to the board here but I have found the exact same thing..... it's tough to find info on these bosch systems. I had a unit installed about a month ago and just wasn't happy with it. It's a 3 ton, 96% split dual fuel propane unit. My dad was in HVAC for 45 years so I've got enough knowledge to be dangerous and knew something wasn't right. The house was set on 72 and wouldn't hold less than 75 of 76, but didn't matter if I set it on 74, would hold about 3-4 deg above. So I called a friend and had him come take a look, the adaptive cooling is now on as well as the accelerated cooling. At the present time the Honeywell thermostat is set to adaptive cooling as well. We found that the installer didn't hook up Y2 from the honewell THM5421R communication board inside to the Y2 on the furnace. Once we did that and turn the option on for the Honeywell TH8321R1001/U thermostat to a 2 stage cool, it gave power to the second stage on the fan and it's ran fine every since. It stays exactly on setpoint. That being said, I have about 25 deg difference between the incoming and outgoing air at the furnace blower and i'm considering changing the jumper on the fan blower from med/high to high and see how that changes the output temperature of the air. I see that @bobboan says he's installed 100's of these units and others have experience, any feedback you have would be greatly apricated. On the thread above, it does seem like the unit runs quite a bit but in the morning has RH>60, however in the evening it has around 50%. The only thing I don't understand is, I've only seen the compressor run around 38hz, when you put it in test mode it will modulate upto about 77 but I've never seen the unit in operation above 38 even on a 100 deg day. Anyone have any input? Thanks!

[humidorlando]

<following> I'm having a similar problem with my 2.0 system which was installed last month. Never seems to ramp up which is fine during the day. It can hold the house steady no problem. But at night when we drop the temp a few degrees it just runs and runs. Takes SEVERAL hours to achieve a 2 degree drop. However if I put it in 'force' mode, it performs like a traditional system and easily cools the house.

[teddy bear]

A 38^F evap temp maxes moisture removal but reduces sensible capacity. Typicall 38^F evap is 60% sensible/40% latent. Total capacity is reduced 10%. During a part load condition colder cooling coils maintain a lower %RH.

47^F evap provides more sensible cooling but less latent. 47^F evap is 75% latent/24%latent. With a significant cooling load of +60% cooling cycle, most homes will be <50%RH @ 75^F.

Evenings and rainy days with low/no sensible cooling loads and +70^F outdoor dew points, will not maintain 50%RH in the home because of low/no sensible cooling loads. Supplemental dehumidification like a small whole house dehumidifier like an Ultra-Aire will maintain 50%RH even with the a/c off.

Better but no magic. Hard to beat a simple well setup single speed a/c with a 30^F split between the return a/c temperature and cooling coil temperature. Plus an adequate sized whole house dehumidifier for the latent load during the non-sensible cooling weather, evenings and rainy days.
Keep us posted.
Regards Teddy Bear

[Special-K]

Bump moved to AOP Residential.

Please don't bump up old threads, it causes a problem with bounced emails.

Thread closed