DORMA RTS88 Series Overhead Concealed Door Closer
The RTS88 is designed to give lasting, dependable service where surface applied units and other types of closers are not suitable, or would interfere with the architectural design. It can be easily installed in wood, aluminum, or hollow metal doors and frames, for single and double-acting doors.
- Concealed installation
- For single and double-acting doors
- Dependable and easy to Install
Aesthetic advantages
Architects are often challenged to design buildings that are both beautiful and functional, down to the last detail. The DORMA RTS88 overhead concealed door closer offers the perfect solution for those who prefer the aesthetic advantages of a concealed door closer.
Vandalism protection
The RTS88 is an excellent replacement closer for problem entrances encountering vandalism of surface applied closers.
Benefits for the contractor
Contractors appreciate the RTS88 closer, because the majority of door and frame preparation is done prior to installation of the unit, resulting in less on-site machining.
Resources:
RTS88 Series Catalog
Manufacturer Resources
Product Specs
- Product Group:
- Door Controls
- Series:
- RTS Series
- Product Subgroup:
- Door Closers - Overhead Concealed
- Product Type:
- Overhead Concealed Door Closers
- Subcategory:
- Concealed Door Closers
- Door Weight:
- 250 lbs
- Door Swing:
- Single Acting
- Commercial/Residential:
- Commercial
- Package Features:
- Hinge or 3/4" Offset ; Wood Door ; Steel Frame
- Product Model:
- RTS28
- Door Hand Direction:
- Non-Handed
- Product Category:
- Door Controls
- Department:
- Door Hardware
Dormakaba RTS28 105 NHO SZ3 600 – Frequently Asked Questions
1) Will the Dorma RTS28 concealed closer work on a wood door in a steel frame?
That's exactly the prep it's built for. The RTS28 configuration of the RTS88 Series is packaged for wood doors in steel frames, hung on butt hinges or a 3/4 inch offset pivot. If your opening is an aluminum door and frame, or a center-hung pivot setup, you want a different RTS88 configuration rather than this one.
2) How heavy a door can the Dorma RTS88 RTS28 closer handle?
Up to 250 lbs. That covers most solid core wood entrance doors at commercial widths. Spring size is what you match to the actual leaf: SZ3 is the standard closing force for 3'-0" to 3'-6" interior doors and 2'-6" to 3'-0" exterior, and SZ4 is the strongest, for 3'-6" to 4'-0" interior and 3'-0" to 3'-6" exterior.
3) Is the RTS28 overhead concealed closer single acting or double acting?
Single acting. The RTS28 swings the door one direction only, so it suits a standard entrance or corridor door with a stop. If you need a door that swings both ways, such as a center hung traffic door, the Norton Rixson 73 Series is a center hung double acting overhead concealed closer rated to 250 lbs.
4) Do I have to order a left hand or right hand Dorma RTS28 closer?
No handing to specify. The RTS28 is non-handed, so the same unit works on a left or right hand opening and you can stock one part number across a building instead of two. What you do have to choose on the order is spring size, cushion stop angle, hold open, finish, and package option.
5) What do I need to specify when ordering a Dorma RTS88 RTS28 concealed closer?
Five choices. Cushion stop at 90 or 105 degrees, hold open yes or no, spring size (BFE, BFI, SZ2, SZ3 or SZ4), finish, and package option. Package option is the one people miss: Standard includes the mounting channel, Less Mounting Channel is for when the channel is already in the frame, and With 5mm Extended Spindle covers a thicker top rail or header condition.
6) What is the closest equivalent to the Dorma RTS28 concealed closer for a 250 lb door?
The Norton Rixson 73 Series overhead concealed closer is rated to 250 lbs, the same door weight the RTS28 carries, and it is a Grade 1 heavy duty unit. The difference is hanging method and swing: the RTS28 is single acting and mounts on hinge or 3/4 inch offset pivot hung wood doors in steel frames, while the 73 Series is center hung and double acting with a cover plate. If the opening is already prepped for offset pivots or butt hinges and swings one way, the RTS28 matches the prep; if the door swings both directions on a center pivot, the 73 Series is the one that suits it.
7) The door is aluminum, not wood. What overhead concealed closer should I use instead of the RTS28?
The RTS28 package is built around a wood door and steel frame on hinge or 3/4 inch offset pivots. For an aluminum door hung on offset pivots, the Norton Rixson 0608 Series is an offset hung overhead concealed closer specified for aluminum doors up to 200 lbs, standard duty. Note the capacity difference: the 0608 tops out at 200 lbs where the RTS28 handles 250 lbs, so weigh the leaf before you commit on a heavy glass-and-aluminum entrance.
8) I need an ANSI Grade 1 overhead concealed closer for a facility spec. What are the options alongside the RTS28?
Three Sargent concealed closers carry Grade 1 heavy duty: the 268 with a cast iron body, the 269 with 180 degree opening capability, and the 278 with an exposed arm. The Norton Rixson 73 Series is Grade 1 heavy duty as well. Each differs in how it presents at the opening - the 278 puts the arm in view where the 268 keeps everything concealed, and the 269 is the one to pull when the leaf has to swing a full 180 degrees. The RTS28 is a commercial unit carrying 250 lb doors, non-handed, which is worth noting if you are standardizing one part number across openings of both hands.
9) Can I drop a Norton Rixson 608 or 700 Series into an opening prepped for the Dorma RTS28?
No, and this is the substitution that looks right on paper and fails at the jamb. The Rixson 608 Series and 700 Series are both center hung overhead concealed closers for 200 lb doors, standard duty. Center hung means the pivot sits inboard on the door centerline and the floor and head prep is cut for that geometry. The RTS28 is built for hinge or 3/4 inch offset pivot hung doors, so the prep locations do not correspond and the door weight the RTS28 covers is 250 lbs against the 200 lbs those two carry. For an offset or butt hinge opening, stay with the offset-hung family.
10) I need a door that opens a full 180 degrees. Will the RTS28 do it?
The RTS28 cushion settings are 90 degrees and 105 degrees, which is the range it is built around. When the opening has to swing a full 180 degrees, the Sargent 269 is the overhead concealed closer specified with 180 degree opening capability, Grade 1 heavy duty. Check the wall and adjacent hardware before ordering either one, since the swing the closer permits still has to clear whatever is beside the jamb.
11) Which spring size do I pick for a barrier free door with a light opening force?
Two barrier free spring sizes are offered on the RTS28, both sized for a 3'-0" door: BFI for interior doors and BFE for exterior. BFE is the exterior version because an exterior leaf sees wind and stack pressure that an interior one doesn't. There's also SZ2 as a light opening force option if you don't need a barrier free spring specifically.
12) Should I use an overhead concealed closer or a surface mounted closer?
An overhead concealed unit like the RTS88 goes up inside the frame header, so nothing shows on the door face. That matters in two situations: a storefront or lobby where a surface closer would break the architectural line, and an entrance that keeps getting vandalized, since there's no exposed body or arm to pull off. The tradeoff is prep. Most of the door and frame machining has to happen before the unit goes in, so it's an easier choice on new work or a frame replacement than as a drop in swap on an existing opening.
13) Does the RTS28 closer hold the door open?
Only if you order it that way. Hold open is a build option on the RTS28, yes or no, so it isn't something you add later in the field. Pair it with the cushion stop angle you need, 90 or 105 degrees, which sets where the door stops on the swing.
14) My existing concealed closer failed but the frame channel is still good. Can I just buy the closer body?
The RTS28 offers a Less Mounting Channel package option for exactly that case, where the channel is already set in the header and you only need the unit. Body only replacements also exist from CRL Jackson, including regular duty in 90 and 105 degree non hold open, a heavy duty 105 degree non hold open, and an adjustable spring power version. Match the existing channel and pivot arrangement before you commit either way.
15) Is there a simpler concealed closer than the Dorma RTS28 if I only need a body replacement?
Yes. The CRL Jackson 20-101M-01 and 20-101M-03 are regular duty overhead concealed closer bodies sold body only, in brown, as non hold open units at 105 degree and 90 degree respectively. Those two degree points line up with the 90 and 105 degree cushion choices the RTS28 offers, and the non hold open function matches an RTS28 ordered without hold open. Because the CRL units are body only, they suit a swap into an existing concealed installation where the channel and hardware stay in place; the RTS28 can also be ordered less mounting channel for that situation.
16) My entrance doors are a mix of widths and some need barrier free opening force. Does the RTS28 cover that or do I need a different closer?
The RTS28 covers it within one model. Spring sizes run SZ2 light opening force, SZ3 standard closing force for 3 foot to 3 foot 6 inch interior and 2 foot 6 inch to 3 foot exterior doors, and SZ4 strongest closing force for 3 foot 6 inch to 4 foot interior and 3 foot to 3 foot 6 inch exterior doors, plus BFI and BFE barrier free light opening force options for interior and exterior 3 foot wide doors. Among the comparables, the CRL Jackson 20-101M-17 takes a different approach as an adjustable spring power overhead concealed closer body, 105 degree no hold open, where the power is set at the unit rather than chosen as a spring size at order.
17) The surface closer on this entrance keeps getting vandalized. What concealed closer replaces it, and what are the alternatives?
The RTS88 is described as an excellent replacement closer for problem entrances encountering vandalism of surface applied closers, and it installs concealed in wood, aluminum, or hollow metal doors and frames. The RTS28 configuration of it handles doors up to 250 lbs, single acting, non-handed, in finishes from 689 aluminum and 690 statuary bronze through 693 black, 695 dark duradonic bronze and 696 gold. If you want the closer fully out of sight, keep the comparison to concealed-body units like the Sargent 268 with its cast iron body rather than the Sargent 278, which places the arm in the open where it can be reached.
18) What finishes does the Dorma RTS28 concealed closer come in?
Seven, and the choice is mostly about the exposed cover plate and arm since the body is buried in the header. 689 Aluminum, 690 Statuary Bronze, 691 Dull Bronze, 693 Black, 695 Dark Duradonic Bronze, 696 Gold, plus 600 Prime Coat if the unit is getting painted to match a frame color on site.
19) Is the Dorma RTS88 closer rated for commercial use or is it a residential closer?
Commercial. The RTS88 is specified for commercial openings, with a 250 lb door capacity and spring sizes running up to SZ4 for 3'-6" to 4'-0" interior doors. That's the range a property manager or facility buyer is working in on entrances, lobbies, and corridor doors, not a residential interior door.
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