Heat Pump dead?

[GBPackerfan]

The DW wanted us to use the Heat pump instead of our HydroHot due to the HH not blowing out of some of the vents in the LR. The BR is toasty, but that’s about it.

I installed the Micro-Air Easy Touch last year and we’ve never even tried to use the HP until today.

The outside temperature right now is 46° and upon turning the thermostat on and switching to HP, I get no activity in the units. They blow AC air with no issue.

My question is is it too cold to run them or is there a separate fuse or breaker for the HP or is it on the same circuit as the AC?

Am I missing something rudimentary?

TIA folks.

[d23haynes57]

46F is definitely not too cold for a heat pump. Are they turning on? It does take some time like 10 or 15 minutes for them to actually blow warm air.

[bentjm]

The MicroAir has a setting that sets the low temperature cutoff for the heat pump side. It may be set way too high.

The MicroAir also uses information from the unit to determine external temperature. I have seen that vary a lot.

When was the last time you used the heat pump?

[Lt Dan]

Also, how long are you running the heat pump when you start up? It will blow cold air for a short time until the evaporator coils heat up.

[RVfixit]

Originally Posted by GBPackerfan

The DW wanted us to use the Heat pump instead of our HydroHot due to the HH not blowing out of some of the vents in the LR. The BR is toasty, but that’s about it.

I installed the Micro-Air Easy Touch last year and we’ve never even tried to use the HP until today.

The outside temperature right now is 46° and upon turning the thermostat on and switching to HP, I get no activity in the units. They blow AC air with no issue.

My question is is it too cold to run them or is there a separate fuse or breaker for the HP or is it on the same circuit as the AC?

Am I missing something rudimentary?

TIA folks.

GBPackersfan- As mentioned by d23haynes57, 46° is about the limit a HP will work. A quick tutorial; when in cooling mode, the AC unit transfers heat to the cold Freon flowing in the evaporative coil with cool air coming out the other side. That heated Freon gas is then cooled again in the condensing coil returning it back to a liquid and the process starts over. That's a very basic explanation but is the jest of how it works.

When calling for heat, the opposite is true. The freon reverses and tries to shed its heat into the evaporator and in turn, blows the warm air into the coach exhausting the cold air to the outside through the condenser. again a very basic explanation but I think you get the idea.

So when the outside air is very cold, the HP is less efficient and takes awhile to build up heat because it can't exhaust much cold air if the outside air is colder than the condenser. Does this make sense?

Just to make sure I understand, do your units run but not cool or do they just not come on? I'm not sure about your coach but some systems will not come on if the outside ambient temp is less than they need to produce heat. Do you have model numbers for your units?

As always, Safe Travels!

[GBPackerfan]

Originally Posted by d23haynes57

46F is definitely not too cold for a heat pump. Are they turning on? It does take some time like 10 or 15 minutes for them to actually blow warm air.

They are not turning on at all.

[GBPackerfan]

Originally Posted by RVfixit

GBPackersfan- As mentioned by d23haynes57, 46° is about the limit a HP will work. A quick tutorial; when in cooling mode, the AC unit transfers heat to the cold Freon flowing in the evaporative coil with cool air coming out the other side. That heated Freon gas is then cooled again in the condensing coil returning it back to a liquid and the process starts over. That's a very basic explanation but is the jest of how it works.

When calling for heat, the opposite is true. The freon reverses and tries to shed its heat into the evaporator and in turn, blows the warm air into the coach exhausting the cold air to the outside through the condenser. again a very basic explanation but I think you get the idea.

So when the outside air is very cold, the HP is less efficient and takes awhile to build up heat because it can't exhaust much cold air if the outside air is colder than the condenser. Does this make sense?

Just to make sure I understand, do your units run but not cool or do they just not come on? I'm not sure about your coach but some systems will not come on if the outside ambient temp is less than they need to produce heat. Do you have model numbers for your units?

As always, Safe Travels!

The AC portion works, just not the heat pump.ill get the model numbers tomorrow and post them.

[GBPackerfan]

Originally Posted by Lt Dan

Also, how long are you running the heat pump when you start up? It will blow cold air for a short time until the evaporator coils heat up.

It’s not coming on at all.

[GBPackerfan]

Originally Posted by bentjm

The MicroAir has a setting that sets the low temperature cutoff for the heat pump side. It may be set way too high.

The MicroAir also uses information from the unit to determine external temperature. I have seen that vary a lot.

When was the last time you used the heat pump?

Last year before we installed the Micro-Air. What setting in the Micro-Air are you referring to?

[bentjm]

Originally Posted by GBPackerfan

Last year before we installed the Micro-Air. What setting in the Micro-Air are you referring to?

I don't remember the specific name of the setting. It was on my previous coach. The manual should show the menu and specific option.

Also, the heat pumps should be good down to the mid 30s. They may reverse cycle fairly often, but they will heat the coach.

[Lt Dan]

I hate to be simplistic, but you have two icons for heat on the Micro Air. One is for heat pump and the other is for furnace. Is this your front, mid or bedroom A/C that's not working on heat pump? It is possible the reversing valve in the A/C is not working switching to heat mode.

Do you have more than one Micro Air? If so, try swapping them out to see if it may be a thermostat problem.

[GBPackerfan]

Originally Posted by Lt Dan

I hate to be simplistic, but you have two icons for heat on the Micro Air. One is for heat pump and the other is for furnace. Is this your front, mid or bedroom A/C that's not working on heat pump? It is possible the reversing valve in the A/C is not working switching to heat mode.

Do you have more than one Micro Air? If so, try swapping them out to see if it may be a thermostat problem.

I’ve changed the Micro-Air from the HH to the heat pump. We have two units and neither are working.

[GBPackerfan]

Originally Posted by bentjm

I don't remember the specific name of the setting. It was on my previous coach. The manual should show the menu and specific option.

Also, the heat pumps should be good down to the mid 30s. They may reverse cycle fairly often, but they will heat the coach.

This is what I found: Gas Heat Override
This function is handled by the control board and not the thermostat. It will activate when the outside temperature falls below the minimum heat pump operating temperature.

I don’t have that function on mine. Mine is a ASY-357-X01

[bentjm]

Originally Posted by GBPackerfan

This is what I found: Gas Heat Override
This function is handled by the control board and not the thermostat. It will activate when the outside temperature falls below the minimum heat pump operating temperature.

I don’t have that function on mine. Mine is a ASY-357-X01

Mine was a 350. It has been over 2 years since I set it up.

If i remember correctly, it was an update that added that functionality.

Have you checked for updates?