Trane Climate Changer

[BIGDICKMaGEE]

I currently have a Trane Climate Changer that serves as a hot/cold deck and the customer wants to know about updating or replacement. I looking to possibly update the control side of things possibly. Any input would be helpful.

[Octopus]

Controls are easy to replace/update whats the condition of the unit, how are the coils evap and cond, compressors motors etc? What year model#

[BIGDICKMaGEE]

The unit is in fairly good shape, we have serviced for last several years. I would suspect it is from the late 60's early 70's. It has a new trane cond. unit about 1 year old. Boiler should be replaced due to age. It has 4 zones that are controlled by proportioning t stats. Boiler has warm weather shut down, a/c has low temp lockout. Hot water valve is honeywell is M7023A 1023
which is faulty. Thought about removing hot water valve and controlling water temp from outsie air reset controll. Looking for ideas!

[flange]

most of those old boys ran at a fairly high static and are probably due for replacement. we just bid a design build to remove three old multizone units. as a value add, we laid the new unit out with fanwall technology for the supply fans, which gives us more flexibility in airflow design, energy saving by using more appropriately sized fans for a given need, more room in the mechanical space by reducing t he footprint of the fan section. size does matter though, fanwall is kinda expensive on smaller applications. if you dont yet know what fanwall is google the word and see what you find.

[BIGDICKMaGEE]

Thanks for the info but i think that the fanwall sysytem would be overkill for this application. This is a 15 ton cond. and a 600,000 btu boiler in a bank. Replacement sounds good but access is limited to basement by a narrow staircase. Controls are the real enemy here and customer is concerned with energy consumption as well. I would like to replace boiler with Weil Mclain Ultra and change out the damper motors, stats, valve, and have a more modern approach to controlling it.

[deux]

Those things love to leak oil on the return bends of the condenser. Make sure the condenser returns are ok. I have used JC for controls updates on a few. You can still buy factory stuff for controls updates also.

[kdocsr05]

I am trying to understand your current design application.

A typical hot deck/cold deck unit would be used in a application were space pressure is critical. Two ducts one for the hot deck and one for the cold deck, the zone temperature controlled with a dual duct mixing box serving the space.

A typical multizone unit would have a hot deck/ cold deck with the flow mixed at the zone discharge duct at the unit. The last time I seen one was about ten years ago. The controls for this application were complicated. If I remember correctly, you had a high selector and low selector relay which developed discharge reset.

Fanwall tech is the way to go.

[BIGDICKMaGEE]

I would have to say i have the second as it is a single duct for each zone off of the unit. Zone dampers either open to hot or cold deck. Fanwall cost may be an issue.

[blackbelt3677]

I am in the middle of doing a few bank jobs with similar setups. We are using a Johnson NCE with IOM's. This is the perfect setup and gives the customer Webaccess if wanted. Our electricians do the install in a couple of days and then a day or two to program and commission and jobs done. Its a good gig and we have quite a few of these jobs.

[kdocsr05]

I would think about a redesign of the systems applications. Is the unit 100% outside air?

The old multizone air handler systems are not energy efficient.

You have some challenges in restoration of the controls. The ddc code for multizone would not be standard for most programmers. The heart of effective energy efficient control lies in the accuracy of the code. The system needs to respond to the loads of five independent zones.

Looks like blackbelt has a current solution. I would like to see the code for the unit, I am trying to work it out myself, just can’t get it, guess I am tired up at 3:30