Lennox Heat Pumps !

[cool it]

Evening All
First I'd like to wish everyone a merry christmas.

Right then the story:-

I went to a bar in Birmingham. They had no heating; they had a company in for 2 years apparently doing the maitenance, but they kept on fobbing them off saying it was working OK.

This is what I found.

Fully ducted system pulling fresh air in over a heater battery and supplying the bar area.

They also have 2 x Lennox package units with a coil in the duct work..
apparently cooling only.

When I investigated I found there was very minimal air flow. Filters I thought. Having searched everywhere for an access door it occured to me that there were not any filters.

Decided to cut an access door into the ducting before the coil.

Found the coil absolutely blocked solid and filters that had deteriorated. There was no filter access door so I also cut a door in for the filters.

OK so now we have air flow the heater battery was working, temperature was going up - all good.

Decided to run up the Lennox units. Dropped indoor set point, heater battery cut out and Lennox units fired up cooling no problems.

Carried out usual checks of all plant customer happy.

Things have been great until the ambient temperature has dropped below 10°C.

The bar is now getting colder, air off temperature has dropped the same difference as the ambient if you get what I mean.

Heater battery still working.

I have been informed today that apparently the Lennox units that they have are in fact heat pumps and the heater battery is just for back up.

The client has told me that they have never really had any heat in there.

I am due to go to site in the morning I have no model numbers on me at the moment but will get all information tommorrow.

Has anyone had much experience with Lennox heat pumps and if so can they point me in the right direction as to possibly why they do not run on heat but they work and change over when cooling is required.

From what I have been told they should be the man source of heat for the place.
I know its a bit vague but will have more info tommorrow

Thanks

[Brian_UK]

Hi Coolit, there could be all sorts of reasons why they are not providing heating.

This can range from dead transformers through broken relays, reversing valve coil failures to control problems.

Defrost timers can also cause problems.

Log on to the Lennox website...
http://www.lennoxcommercial.com/support/sign-in.asp

and search the technical manuals there.

I came across a few units on top of a Sainsbury's and found the website quite usefull.

Good luck with it.

[cool it]

Hi Brian thanks for the link it will be very helpfull.
I have had a look on there and without having the details to hand its proving quite difficult to find one that looks remotely like them.
Think I will go to site tommorrow and try and dig any drawings etc out from the closet.
then i will post model numbers on here.
thanks again

[NoNickName]

Looks like it's rooftop with heater backup or electric reheating for dehumidification, not a heatpump. Is it reversible? Do you see a 4-way valve?

[Toolman]

If the idiots who installed it omitted the filter access they could have done some more crazy things during installation like the Thermostat is wrong and is only a cooling only stat , and of course does it have the reversing valves for heating you say heat pump but sometimes this is to sound good and the just use heater banks .