9
votes
Is HVAC heat pump condenser better mounted to a wall or a flat roof?
The condenser you show is common to mini split systems and work better when in the shade.
Since the roof offers no shade, I would recommend a wall mounting. Most manufacturers offer a wall mounting ...
- 29.2k
8
votes
Accepted
Best way to re-route the water from AC drip line
Two proposals
1- Extend the drip pipe to the grass using a pvc pipe of proper diameter
2- My preferred (I do it now), use a bucked to capture the very clean no minerals or calcium water (soft) to ...
- 17.4k
7
votes
Accepted
Couple of questions on the outside unit of a split heat and A/C installation
A refrigeration system (air conditioning, and also heat pumps) pumps refrigerant. The refrigerant is in liquid phase in the smaller tube (the "liquid line") and in gaseous phase in the ...
- 30.6k
6
votes
Best way to re-route the water from AC drip line
Put a "gutter splash block" (standard item) under it to route the water away from the house to the grass while keeping the pipe short (less potential of clogging the pipe and backing up .vs. ...
- 214k
6
votes
What does "Auxilliary heat is running too long" mean in my ecobee
Simply put, a heat pump moves heat from outside air (or better, from the ground, which maintains a warmer temperature through winter than does the air.) This is more efficient than resistive heating, ...
- 7,389
5
votes
Best way to re-route the water from AC drip line
One thing that is done in some areas is the condensate drain line is run to a location under a bathroom sink and is tied into the drain line before the P-trap. All condensate goes down the houses ...
- 27.9k
5
votes
Restoring automatic selection of natural gas heat vs. heat pump based on outdoor temperature
I don't know why it has been so hard to figure this out. My guess is that Honeywell is only interested in Honeywell products (though it may turn out they have something that will do exactly what you ...
5
votes
Is HVAC heat pump condenser better mounted to a wall or a flat roof?
If you would set this on the roof, it would have to be on a raised platform to avoid immersion of the lower part of the unit in heavy rains.
Best mounting would be on a wall. The low wall might have ...
- 21.9k
4
votes
Accepted
Heat pump condensation line pump
We don't know how the installer hooked up the condensate pump, but one way to hook it up is to inhibit both heating and cooling if the condensate pump fails.
If you have a Little Giant condensate pump ...
- 11.3k
4
votes
Is a 9000 BTU split heat pump oversized for cooling a 156 square feet room (Quebec climate)?
Oversized is good in a mini-split.
Who cares? "Oversized" is not a modern concept.
It's a mini-split with a variable speed drive. All the hand-wringing about over-sizing A/C units only ...
4
votes
Best way to re-route the water from AC drip line
In my location 95% of homes have an AC unit. The codes for most counties say the condensate line must terminate at least 12" away from a building foundation and have a Trap. (Here they are called ...
- 29.2k
4
votes
How cold can it get outdoors before air source heat pump sees damage from running?
I assume that you've tried to find the freezing point of R134a at various pressures and you were stymied. That's because the freezing point of almost all pure liquids (except water) barely changes ...
- 11.3k
4
votes
Accepted
Minisplit Head units produce heat far beyond set temp
The issue has been resolved.
Root cause
The culprit was a faulty management board on the compressor.
Diagnosis
One of the terminals was throwing irregular voltages. The manufacturer said this could ...
- 61
4
votes
Accepted
Cost impact of installing a heat pump vs. improving insulation
Fixing insulation and infiltration (e.g., caulking and house wrap) should be first priority, whether burning gas or using electricity in a heat pump. Many public utilities provide free inspection of ...
- 7,389
3
votes
Heat Pumps that can add moisture to dry indoor air in winter
I think you're mistaken. A heat pump can't add water to the air. Probably someone described their HVAC system that includes a humidifier as a heat pump, not knowing any better.
- 21.2k
3
votes
Configuring FHW heating system as a backup to minisplit
Without seeing your actual layout, who can guess as to freezing? You need to take temperature measurements on pipes and radiators when it's bitter cold. A non-contact IR thermometer is useful for ...
- 11.3k
3
votes
Why do variable speed heat pumps need a proprietary (communicating) thermostat and why does mine not need one?
I've had the same question, and I found this article by the Northeast Energy Alliance that discusses options for communicating thermostats for variable speed inverter type heat pumps.
The takeaway is ...
- 31
3
votes
Accepted
Will a frozen up Evaporator Coil in a heat pump cause the Air Handler Fan Motor to die?
When an evaporator coil freezes this means its surface is literally covered with ice -- frozen water. As ice begins to form it starts blocking air flow through the coil. The reduced air flow leads to ...
- 30.6k
3
votes
Can I use a UPS in front of my A/C heat pump, to reduce surges in the house?
Most homes have a heat pump outside, but it's a plain old 7-13 SEER non-reversible "air conditioner" with bang-bang controls. Meaning at opportune times it goes "SKREEhrmmmmmmmmmmm"...
3
votes
Sizing charts for air conditioner or heat pump for humidity rather than cooling? 1-stage vs. 2-stage? 3-stage?
ACCA Manuals J and S are your friend
The official, Code-sanctioned way to size HVAC equipment comes from ACCA Manuals J on load calculation and S on equipment selection. Manual J in particular is ...
- 83.4k
3
votes
AOSmith Voltex Heat Pump Water Pump Stuck on Vacation Mode
Figured it out, it was a combination of user error and a misleading user interface.
I had to tap the vacation mode button again to toggle off vacation mode. Half the time it would default back to ...
- 357
3
votes
Accepted
Heat Pump Air Exchanger efficiency gains in Snow/Cold
The wind is the same air you're pulling heat from anyway. A "small" structure seems likely to impede air-flow if it's got sides.
Keeping the snow from falling on it with the roof might have ...
- 214k
3
votes
Can heat pump completely replace natural gas furnace
Depends on how old and cruddy the heat pump design they're offering is.
Technology Connections covers this in their heat pump series. The old-guard American makers like Trane and Lennox are not happy ...
3
votes
What does "Auxilliary heat is running too long" mean in my ecobee
I assume this is a default setting, to provide a warning message in the stated situation. Whether or not it means anything depends on a few things, including whether or not you've had the system long ...
- 601
3
votes
Possibility of using a heat pump to exchange cool air from a ground floor with third floor room
What you've suggested is possible, yes, however residential-grade commercially available systems don't support that mode. There exist mini split heat pump systems supporting multiple indoor units but ...
- 30.6k
2
votes
LED lights constantly flicker when heat pump is running
Moovair, Bosch, and many other manufacturers are all a Midea unit re-branded. I can confirm Midea made a design change to one of the boards on some of their heat-pumps (3t and 4t) to address this ...
- 31
2
votes
Is a 9000 BTU split heat pump oversized for cooling a 156 square feet room (Quebec climate)?
It's oversized
I have tried many sizing calculators, methods, spreadsheets, etc, and for the room size of 156 square feet (13x12 with 9 feet ceiling), the prescribed BTU requirements range from aprox ...
- 1,902
2
votes
Accepted
What data is available to support decisions about thermostat set point with mini split heat exchangers?
This is a function of pump (affinity) laws
Heat removal is more or less proportional to the flow rate of the refrigerant.
But power consumed is proportional to the cube of flow rate of the refrigerant....
- 1,902
2
votes
Is heating load related to volume of area/surface?
1 is equivalent to 2 as the "some factor" includes the U values etc
2 is based on the u value of each wall surface and it is those surfaces that loose the heat.
Some of us when we designed ...
- 27.4k
2
votes
Accepted
How to do heat load calculations for distribution with common return and/or open floor concept
(Exterior) Wall area * wall U-value. If you have walls with different levels of insulation, they are added up separately after their separate U-values are multiplied by each area.
(Exterior) Window ...
- 214k
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